Block Module

Abstract Block

Base block class

class lava.lib.dl.slayer.block.base.AbstractAffine(neuron_params, in_neurons, out_neurons, weight_scale=1, weight_norm=False, pre_hook_fx=None, dynamics=True, mask=None, count_log=False)

Bases: Module

Abstract affine transform class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • dynamics (bool, optional) – flag to enable neuron dynamics. If False, only the dendrite current is returned. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractAverage(num_outputs, count_log=False)

Bases: Module

Abstract average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractConv(neuron_params, in_features, out_features, kernel_size, stride=1, padding=0, dilation=1, groups=1, weight_scale=1, weight_norm=False, pre_hook_fx=None, delay=False, delay_shift=True, count_log=False)

Bases: Module

Abstract convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input must be in NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractConvT(neuron_params, in_features, out_features, kernel_size, stride=1, padding=0, dilation=1, groups=1, weight_scale=1, weight_norm=False, pre_hook_fx=None, delay=False, delay_shift=True, count_log=False)

Bases: Module

Abstract convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)
property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractDense(neuron_params, in_neurons, out_neurons, weight_scale=1, weight_norm=False, pre_hook_fx=None, delay=False, delay_shift=True, mask=None, count_log=False)

Bases: Module

Abstract dense block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractFlatten(count_log=False)

Bases: Module

Abstract flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

class lava.lib.dl.slayer.block.base.AbstractInput(neuron_params=None, weight=None, bias=None, delay_shift=True, count_log=False)

Bases: Module

Abstract input block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractKWTA(neuron_params, in_neurons, out_neurons, num_winners, self_excitation=0.5, weight_scale=1, weight_norm=False, pre_hook_fx=None, delay_shift=True, requires_grad=True, count_log=False)

Bases: Module

Abstract K-Winner-Takes-All block class. This should never be instantiated on its own. The formulation is described as below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1] + \alpha\,(N-2K)\right)\\ \mathbf{R} = \begin{bmatrix} a &-1 &\cdots &-1\\ -1 & a &\cdots &-1\\ \vdots &\vdots &\ddots &\vdots\\ -1 &-1 &\cdots & a \end{bmatrix},\qquad |a| < 1

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • num_winners ([type]) – number of winners.

  • self_excitation (float, optional) – self excitation factor. Defaults to 0.5.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

clamp()
export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractPool(neuron_params, kernel_size, stride=None, padding=0, dilation=1, weight_scale=1, weight_norm=False, pre_hook_fx=None, delay=False, delay_shift=True, count_log=False)

Bases: Module

Abstract input block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input must be in NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractRecurrent(neuron_params, in_neurons, out_neurons, weight_scale=1, weight_norm=False, pre_hook_fx=None, requires_grad=True, delay=False, delay_shift=True, count_log=False)

Bases: Module

Abstract recurrent block class. This should never be instantiated on its own. The recurrent formulation is described below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1]\right)

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter.Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)
forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractResidual(*args, **kwargs)

Bases: Module

class lava.lib.dl.slayer.block.base.AbstractTimeDecimation(factor, count_log=False)

Bases: Module

Abstract time decimation block class. This should never be instantiated on its own.

Parameters:
  • factor (int, optional) – number of time units to decimate in a single bin. Must be in powers of 2.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)

Forward computation method. The input can be either of NCT or NCHWT format.

property shape

Shape of the block.

class lava.lib.dl.slayer.block.base.AbstractUnpool(neuron_params, kernel_size, stride=None, padding=0, dilation=1, weight_scale=1, weight_norm=False, pre_hook_fx=None, delay=False, delay_shift=True, count_log=False)

Bases: Module

Abstract Unpool block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)
property shape

Shape of the block.

lava.lib.dl.slayer.block.base.step_delay(module, x)

Step delay computation. This simulates the 1 timestep delay needed for communication between layers.

Parameters:
  • module (module) – python module instance

  • x (torch.tensor) – Tensor data to be delayed.

CUrrent BAsed Leaky Integrate and Fire (CUBA) Block

CUBA-LIF layer blocks

class lava.lib.dl.slayer.block.cuba.AbstractCuba(*args, **kwargs)

Bases: Module

Abstract block class for Current Based Leaky Integrator neuron. This should never be instantiated on it’s own.

class lava.lib.dl.slayer.block.cuba.Affine(*args, **kwargs)

Bases: AbstractCuba, AbstractAffine

CUBA LIF affine transform class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • dynamics (bool, optional) – flag to enable neuron dynamics. If False, only the dendrite current is returned. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Average(*args, **kwargs)

Bases: AbstractAverage

CUBA LIF average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Conv(*args, **kwargs)

Bases: AbstractCuba, AbstractConv

CUBA LIF convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.ConvT(*args, **kwargs)

Bases: AbstractCuba, AbstractConvT

CUBA LIF convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Dense(*args, **kwargs)

Bases: AbstractCuba, AbstractDense

CUBA LIF dense block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Flatten(*args, **kwargs)

Bases: AbstractFlatten

CUBA LIF flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Input(*args, **kwargs)

Bases: AbstractCuba, AbstractInput

CUBA LIF input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.KWTA(*args, **kwargs)

Bases: AbstractCuba, AbstractKWTA

CUBA LIF K-Winner-Takes-All block class. This should never be instantiated on its own. The formulation is described as below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1] + \alpha\,(N-2K)\right)\\ \mathbf{R} = \begin{bmatrix} a &-1 &\cdots &-1\\ -1 & a &\cdots &-1\\ \vdots &\vdots &\ddots &\vdots\\ -1 &-1 &\cdots & a \end{bmatrix},\qquad |a| < 1

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • num_winners ([type]) – number of winners.

  • self_excitation (float, optional) – self excitation factor. Defaults to 0.5.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Pool(*args, **kwargs)

Bases: AbstractCuba, AbstractPool

CUBA LIF input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Recurrent(*args, **kwargs)

Bases: AbstractCuba, AbstractRecurrent

CUBA LIF recurrent block class. This should never be instantiated on its own. The recurrent formulation is described below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1]\right)

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter.Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.TimeDecimation(*args, **kwargs)

Bases: AbstractTimeDecimation

CUBA LIF time decimation block class. This should never be instantiated on its own.

Parameters:
  • factor (int, optional) – number of time units to decimate in a single bin. Must be in powers of 2.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.cuba.Unpool(*args, **kwargs)

Bases: AbstractCuba, AbstractUnpool

CUBA LIF Unpool block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of CUBA LIF neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

Resonate and Fire (R&F) Block

Resonate and Fire layer blocks.

class lava.lib.dl.slayer.block.rf.AbstractRF(*args, **kwargs)

Bases: Module

Abstract Resonate and Fire block class. This should never be instantiated on it’s own.

class lava.lib.dl.slayer.block.rf.Affine(*args, **kwargs)

Bases: AbstractRF, AbstractAffine

Resonate & Fire affine transform class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • dynamics (bool, optional) – flag to enable neuron dynamics. If False, only the dendrite current is returned. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Average(*args, **kwargs)

Bases: AbstractAverage

Resonate & Fire average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Conv(*args, **kwargs)

Bases: AbstractRF, AbstractConv

Resonate & Fire convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.ConvT(*args, **kwargs)

Bases: AbstractRF, AbstractConvT

Resonate & Fire convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Dense(*args, **kwargs)

Bases: AbstractRF, AbstractDense

Resonate & Fire dense block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Flatten(*args, **kwargs)

Bases: AbstractFlatten

Resonate & Fire flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Input(*args, **kwargs)

Bases: AbstractRF, AbstractInput

Resonate & Fire input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.KWTA(*args, **kwargs)

Bases: AbstractRF, AbstractKWTA

Resonate & Fire K-Winner-Takes-All block class. This should never be instantiated on its own. The formulation is described as below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1] + \alpha\,(N-2K)\right)\\ \mathbf{R} = \begin{bmatrix} a &-1 &\cdots &-1\\ -1 & a &\cdots &-1\\ \vdots &\vdots &\ddots &\vdots\\ -1 &-1 &\cdots & a \end{bmatrix},\qquad |a| < 1

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • num_winners ([type]) – number of winners.

  • self_excitation (float, optional) – self excitation factor. Defaults to 0.5.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Pool(*args, **kwargs)

Bases: AbstractRF, AbstractPool

Resonate & Fire input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Recurrent(*args, **kwargs)

Bases: AbstractRF, AbstractRecurrent

Resonate & Fire recurrent block class. This should never be instantiated on its own. The recurrent formulation is described below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1]\right)

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter.Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.TimeDecimation(*args, **kwargs)

Bases: AbstractTimeDecimation

Resonate & Fire time decimation block class. This should never be instantiated on its own.

Parameters:
  • factor (int, optional) – number of time units to decimate in a single bin. Must be in powers of 2.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf.Unpool(*args, **kwargs)

Bases: AbstractRF, AbstractUnpool

Resonate & Fire Unpool block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

Resonate and Fire Izhikevich (R&F Iz) Block

Resonate and Fire - Izhikevich layer blocks.

class lava.lib.dl.slayer.block.rf_iz.AbstractRFIz(*args, **kwargs)

Bases: Module

Abstract Resonate and Fire - Izhikevich block class. This should never be instantiated on it’s own.

class lava.lib.dl.slayer.block.rf_iz.Affine(*args, **kwargs)

Bases: AbstractRFIz, AbstractAffine

Resonate & Fire Izhikevich affine transform class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • dynamics (bool, optional) – flag to enable neuron dynamics. If False, only the dendrite current is returned. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Average(*args, **kwargs)

Bases: AbstractAverage

Resonate & Fire Izhikevich average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Conv(*args, **kwargs)

Bases: AbstractRFIz, AbstractConv

Resonate & Fire Izhikevich convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.ConvT(*args, **kwargs)

Bases: AbstractRFIz, AbstractConvT

Resonate & Fire Izhikevich convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Dense(*args, **kwargs)

Bases: AbstractRFIz, AbstractDense

Resonate & Fire Izhikevich dense block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Flatten(*args, **kwargs)

Bases: AbstractFlatten

Resonate & Fire Izhikevich flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Input(*args, **kwargs)

Bases: AbstractRFIz, AbstractInput

Resonate & Fire Izhikevich input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.KWTA(*args, **kwargs)

Bases: AbstractRFIz, AbstractKWTA

Resonate & Fire Izhikevich K-Winner-Takes-All block class. This should never be instantiated on its own. The formulation is described as below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1] + \alpha\,(N-2K)\right)\\ \mathbf{R} = \begin{bmatrix} a &-1 &\cdots &-1\\ -1 & a &\cdots &-1\\ \vdots &\vdots &\ddots &\vdots\\ -1 &-1 &\cdots & a \end{bmatrix},\qquad |a| < 1

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • num_winners ([type]) – number of winners.

  • self_excitation (float, optional) – self excitation factor. Defaults to 0.5.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Pool(*args, **kwargs)

Bases: AbstractRFIz, AbstractPool

Resonate & Fire Izhikevich input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Recurrent(*args, **kwargs)

Bases: AbstractRFIz, AbstractRecurrent

Resonate & Fire Izhikevich recurrent block class. This should never be instantiated on its own. The recurrent formulation is described below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1]\right)

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter.Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.TimeDecimation(*args, **kwargs)

Bases: AbstractTimeDecimation

Resonate & Fire Izhikevich time decimation block class. This should never be instantiated on its own.

Parameters:
  • factor (int, optional) – number of time units to decimate in a single bin. Must be in powers of 2.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.rf_iz.Unpool(*args, **kwargs)

Bases: AbstractRFIz, AbstractUnpool

Resonate & Fire Izhikevich Unpool block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of RF-Izhikevich neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

Adaptive Leaky Integrate and Fire (ALIF) Block

Adaptive Leaky Integrate and Fire block layers.

class lava.lib.dl.slayer.block.alif.AbstractALIF(*args, **kwargs)

Bases: Module

Abstract Leaky Integrae and Fire block. This should never be instantiated on it’s own.

class lava.lib.dl.slayer.block.alif.Average(*args, **kwargs)

Bases: AbstractAverage

Adaptive LIF average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.Conv(*args, **kwargs)

Bases: AbstractALIF, AbstractConv

Adaptive LIF convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.ConvT(*args, **kwargs)

Bases: AbstractALIF, AbstractConvT

Adaptive LIF convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.Dense(*args, **kwargs)

Bases: AbstractALIF, AbstractDense

Adaptive LIF dense block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.Flatten(*args, **kwargs)

Bases: AbstractFlatten

Adaptive LIF flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.Input(*args, **kwargs)

Bases: AbstractALIF, AbstractInput

Adaptive LIF input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.KWTA(*args, **kwargs)

Bases: AbstractALIF, AbstractKWTA

Adaptive LIF K-Winner-Takes-All block class. This should never be instantiated on its own. The formulation is described as below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1] + \alpha\,(N-2K)\right)\\ \mathbf{R} = \begin{bmatrix} a &-1 &\cdots &-1\\ -1 & a &\cdots &-1\\ \vdots &\vdots &\ddots &\vdots\\ -1 &-1 &\cdots & a \end{bmatrix},\qquad |a| < 1

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • num_winners ([type]) – number of winners.

  • self_excitation (float, optional) – self excitation factor. Defaults to 0.5.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.Pool(*args, **kwargs)

Bases: AbstractALIF, AbstractPool

Adaptive LIF input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.Recurrent(*args, **kwargs)

Bases: AbstractALIF, AbstractRecurrent

Adaptive LIF recurrent block class. This should never be instantiated on its own. The recurrent formulation is described below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1]\right)

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter.Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.TimeDecimation(*args, **kwargs)

Bases: AbstractTimeDecimation

Adaptive LIF time decimation block class. This should never be instantiated on its own.

Parameters:
  • factor (int, optional) – number of time units to decimate in a single bin. Must be in powers of 2.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.alif.Unpool(*args, **kwargs)

Bases: AbstractALIF, AbstractUnpool

Adaptive LIF Unpool block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive LIF neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

Adaptive Resonate and Fire (Ad R&F) Block

Adaptive Resonate and Fire - Phase Threshold layer

class lava.lib.dl.slayer.block.adrf.AbstractADRF(*args, **kwargs)

Bases: Module

Abstract Adaptive Resonate and Fire block. This should never be instantiated on its own.

class lava.lib.dl.slayer.block.adrf.Average(*args, **kwargs)

Bases: AbstractAverage

Adaptive Resonate & Fire average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.Conv(*args, **kwargs)

Bases: AbstractADRF, AbstractConv

Adaptive Resonate & Fire convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.ConvT(*args, **kwargs)

Bases: AbstractADRF, AbstractConvT

Adaptive Resonate & Fire convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.Dense(*args, **kwargs)

Bases: AbstractADRF, AbstractDense

Adaptive Resonate & Fire dense block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.Flatten(*args, **kwargs)

Bases: AbstractFlatten

Adaptive Resonate & Fire flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.Input(*args, **kwargs)

Bases: AbstractADRF, AbstractInput

Adaptive Resonate & Fire input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.KWTA(*args, **kwargs)

Bases: AbstractADRF, AbstractKWTA

Adaptive Resonate & Fire K-Winner-Takes-All block class. This should never be instantiated on its own. The formulation is described as below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1] + \alpha\,(N-2K)\right)\\ \mathbf{R} = \begin{bmatrix} a &-1 &\cdots &-1\\ -1 & a &\cdots &-1\\ \vdots &\vdots &\ddots &\vdots\\ -1 &-1 &\cdots & a \end{bmatrix},\qquad |a| < 1

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • num_winners ([type]) – number of winners.

  • self_excitation (float, optional) – self excitation factor. Defaults to 0.5.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.Pool(*args, **kwargs)

Bases: AbstractADRF, AbstractPool

Adaptive Resonate & Fire input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.Recurrent(*args, **kwargs)

Bases: AbstractADRF, AbstractRecurrent

Adaptive Resonate & Fire recurrent block class. This should never be instantiated on its own. The recurrent formulation is described below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1]\right)

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter.Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.TimeDecimation(*args, **kwargs)

Bases: AbstractTimeDecimation

Adaptive Resonate & Fire time decimation block class. This should never be instantiated on its own.

Parameters:
  • factor (int, optional) – number of time units to decimate in a single bin. Must be in powers of 2.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf.Unpool(*args, **kwargs)

Bases: AbstractADRF, AbstractUnpool

Adaptive Resonate & Fire Unpool block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

Adaptive Resonate and Fire Izhikevich (Ad R&F Iz) Block

Adaptive Resonate and Fire - Izhikevich layer blocks

class lava.lib.dl.slayer.block.adrf_iz.AbstractADRFIZ(*args, **kwargs)

Bases: Module

Abstract Adaptive Resonate and Fire - Izhikevich block. This should never be instantiated on its own.

class lava.lib.dl.slayer.block.adrf_iz.Average(*args, **kwargs)

Bases: AbstractAverage

Adaptive Resonate & Fire Izhikevich average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.Conv(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractConv

Adaptive Resonate & Fire Izhikevich convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.ConvT(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractConvT

Adaptive Resonate & Fire Izhikevich convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.Dense(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractDense

Adaptive Resonate & Fire Izhikevich dense block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.Flatten(*args, **kwargs)

Bases: AbstractFlatten

Adaptive Resonate & Fire Izhikevich flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.Input(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractInput

Adaptive Resonate & Fire Izhikevich input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.KWTA(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractKWTA

Adaptive Resonate & Fire Izhikevich K-Winner-Takes-All block class. This should never be instantiated on its own. The formulation is described as below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1] + \alpha\,(N-2K)\right)\\ \mathbf{R} = \begin{bmatrix} a &-1 &\cdots &-1\\ -1 & a &\cdots &-1\\ \vdots &\vdots &\ddots &\vdots\\ -1 &-1 &\cdots & a \end{bmatrix},\qquad |a| < 1

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • num_winners ([type]) – number of winners.

  • self_excitation (float, optional) – self excitation factor. Defaults to 0.5.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.Pool(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractPool

Adaptive Resonate & Fire Izhikevich input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.Recurrent(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractRecurrent

Adaptive Resonate & Fire Izhikevich recurrent block class. This should never be instantiated on its own. The recurrent formulation is described below:

s_\text{out}[t] = f_s\left(\mathbf{W}\,s_\text{in}[t] + \mathbf{R}\,s_{out}[t-1]\right)

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter.Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • requires_grad (bool, optional) – flag for learnable recurrent synapse. Defaults to True.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.TimeDecimation(*args, **kwargs)

Bases: AbstractTimeDecimation

Adaptive Resonate & Fire Izhikevich time decimation block class. This should never be instantiated on its own.

Parameters:
  • factor (int, optional) – number of time units to decimate in a single bin. Must be in powers of 2.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.adrf_iz.Unpool(*args, **kwargs)

Bases: AbstractADRFIZ, AbstractUnpool

Adaptive Resonate & Fire Izhikevich Unpool block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Adaptive RF-Izhikevich neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

Sigma Delta Block (SDN)

Sigma Delta layer blocks.

class lava.lib.dl.slayer.block.sigma_delta.AbstractSDRelu(*args, **kwargs)

Bases: Module

Abstract Sigma Delta block class. This should never be instantiated on it’s own.

class lava.lib.dl.slayer.block.sigma_delta.Average(*args, **kwargs)

Bases: AbstractAverage

Sigma Delta average block class. This should never be instantiated on its own.

Parameters:
  • num_outputs (int) – number of output population groups.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.sigma_delta.Conv(*args, **kwargs)

Bases: AbstractSDRelu, AbstractConv

Sigma Delta convolution block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Sigma Delta neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolution stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolution padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolution dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.sigma_delta.ConvT(*args, **kwargs)

Bases: AbstractSDRelu, AbstractConvT

Sigma Delta convolution Traspose block class. This should never be instantiated on its own.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Sigma Delta neuron parameter. Defaults to None.

  • in_features (int) – number of input features.

  • out_features (int) – number of output features.

  • kernel_size (int) – kernel size.

  • stride (int or tuple of two ints, optional) – convolutionT stride. Defaults to 1.

  • padding (int or tuple of two ints, optional) – convolutionT padding. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – convolutionT dilation. Defaults to 1.

  • groups (int, optional) – number of blocked connections. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.sigma_delta.Dense(*args, **kwargs)

Bases: AbstractSDRelu, AbstractDense

Sigma Delta dense block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Sigma Delta neuron parameter. Defaults to None.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • mask (bool array, optional) – boolean synapse mask that only enables relevant synapses. None means no masking is applied. Defaults to None.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.sigma_delta.Flatten(*args, **kwargs)

Bases: AbstractFlatten

Sigma Delta flatten block class. This should never be instantiated on its own.

Parameters:

count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.sigma_delta.Input(*args, **kwargs)

Bases: AbstractSDRelu, AbstractInput

Sigma Delta input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Sigma Delta neuron parameter. Defaults to None.

  • weight (float, optional) – weight for affine transform of input. None means no weight scaling. Defaults to None.

  • bias (float, optional) – bias for affine transform of input. None means no bias shift. Defaults to None.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

forward(x)
class lava.lib.dl.slayer.block.sigma_delta.Output(neuron_params, in_neurons, out_neurons, weight_scale=1, weight_norm=False, count_log=False)

Bases: AbstractSDRelu

Sigma Delta output block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict) – a dictionary of sigma delta neuron parameters.

  • in_neurons (int) – number of input neurons.

  • out_neurons (int) – number of output neurons.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

export_hdf5(handle)

Hdf5 export method for the block.

Parameters:

handle (file handle) – hdf5 handle to export block description.

forward(x)
property shape

Shape of the block.

class lava.lib.dl.slayer.block.sigma_delta.Pool(*args, **kwargs)

Bases: AbstractSDRelu, AbstractPool

Sigma Delta input block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Sigma Delta neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of pooling kernel.

  • stride (int or tuple of two ints, optional) – stride of pooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of pooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of pooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

class lava.lib.dl.slayer.block.sigma_delta.Unpool(*args, **kwargs)

Bases: AbstractSDRelu, AbstractUnpool

Sigma Delta Unpool block class. The block is 8 bit quantization ready.

Parameters:
  • neuron_params (dict, optional) – a dictionary of Sigma Delta neuron parameter. Defaults to None.

  • kernel_size (int or tuple of two ints) – size of unpooling kernel.

  • stride (int or tuple of two ints, optional) – stride of unpooling operation. Defaults to None.

  • padding (int or tuple of two ints, optional) – padding of unpooling operation. Defaults to 0.

  • dilation (int or tuple of two ints, optional) – dilation of unpooling kernel. Defaults to 1.

  • weight_scale (int, optional) – weight initialization scaling. Defaults to 1.

  • weight_norm (bool, optional) – flag to enable weight normalization. Defaults to False.

  • pre_hook_fx (optional) – a function pointer or lambda that is applied to synaptic weights before synaptic operation. None means no transformation. Defaults to None.

  • delay (bool, optional) – flag to enable axonal delay. Defaults to False.

  • delay_shift (bool, optional) – flag to simulate spike propagation delay from one layer to next. Defaults to True.

  • count_log (bool, optional) – flag to return event count log. If True, an additional value of average event rate is returned. Defaults to False.

Module contents