Package topo :: Package sheet :: Module basic :: Class JointNormalizingCFSheet

Class JointNormalizingCFSheet

A type of CFSheet extended to support joint sum-based normalization.

For L1 normalization, joint normalization means normalizing the sum of (the absolute values of) all weights in a set of corresponding CFs in different Projections, rather than only considering weights in the same CF.

This class makes it possible for a model to use joint normalization, by providing a mechanism for grouping Projections (see _port_match), plus a learn() function that computes the joint sums. Joint normalization also requires having ConnectionField store and return a norm_total for each neuron, and having an TransferFn that will respect this norm_total rather than the strict total of the ConnectionField's weights. At present, CFPOF_DivisiveNormalizeL1 and CFPOF_DivisiveNormalizeL1_opt do use norm_total; others can be extended to do something similar if necessary.

To enable joint normalization, you can declare that all the incoming connections that should be normalized together each have a dest_port of:

dest_port=('Activity','JointNormalize', 'AfferentGroup1'),

Then all those that have this dest_port will be normalized together, as long as an appropriate TransferFn is being used.

Nested Classes

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Inherited from param.parameterized.Parameterized: __metaclass__

Instance Methods

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start(self)
Called by the simulation when the EventProcessor is added to the simulation.

source code

_normalize_weights(self, active_units_mask=True)
Apply the weights_output_fns for every group of Projections.

source code

learn(self)
Call the learn() method on every Projection to the Sheet, and call the output functions (jointly if necessary).

source code

Inherited from base.cf.CFSheet: release_unit_view, update_unit_view

Inherited from base.projection.ProjectionSheet: __init__, activate, input_event, n_bytes, n_conns, override_plasticity_state, present_input, process_current_time, projections, restore_plasticity_state

Inherited from base.projection.ProjectionSheet (private): _dest_connect, _grouped_in_projections, _port_match

Inherited from base.sheet.Sheet: activity_len, release_sheet_view, row_col_sheetcoords, sheet_cols, sheet_rows, sheetcoords_of_idx_grid, state_pop, state_push

Inherited from base.sheet.Sheet (private): _get_density

Inherited from base.simulation.EventProcessor: script_repr, send_output

Inherited from base.simulation.EventProcessor (private): _src_connect

Inherited from param.parameterized.Parameterized: __getstate__, __repr__, __setstate__, __str__, debug, defaults, force_new_dynamic_value, get_param_values, get_value_generator, inspect_value, message, print_param_values, set_default, set_dynamic_time_fn, set_param, verbose, warning

Inherited from param.parameterized.Parameterized (private): _add_parameter, _instantiate_param, _set_name, _setup_params

Inherited from base.sheetcoords.SheetCoordinateSystem: closest_cell_center, matrix2sheet, matrixidx2sheet, sheet2matrix, sheet2matrixidx, sheetcoordinates_of_matrixidx

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __setattr__, __sizeof__, __subclasshook__

Class Methods

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Inherited from param.parameterized.Parameterized: params, print_param_defaults

Class Variables

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joint_norm_fn = param.Callable(default= compute_joint_norm_tot...
Function to use to compute the norm_total for each CF in each projection from a group to be normalized jointly.

name = <param.parameterized.String object at 0xa9f6e6c>
String identifier for this object.

Inherited from base.cf.CFSheet: measure_maps, precedence

Inherited from base.projection.ProjectionSheet: allow_skip_non_responding_units, dest_ports, mask, src_ports

Inherited from base.sheet.Sheet: apply_output_fns, layout_location, nominal_bounds, nominal_density, output_fns, plastic, row_precedence

Inherited from param.parameterized.Parameterized: print_level

Properties

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Inherited from base.sheet.Sheet: density

Inherited from base.sheetcoords.SheetCoordinateSystem: shape, xdensity, ydensity

Inherited from object: __class__

Method Details

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start(self)

source code

Called by the simulation when the EventProcessor is added to the simulation.

If an EventProcessor needs to have any code run when it is added to the simulation, the code can be put into this method in the subclass.

Overrides: base.simulation.EventProcessor.start: (inherited documentation)

_normalize_weights(self, active_units_mask=True)

source code

Apply the weights_output_fns for every group of Projections.

If active_units_mask is True, only active units will have their weights normalized.

learn(self)

source code

Call the learn() method on every Projection to the Sheet, and call the output functions (jointly if necessary).

Overrides: base.projection.ProjectionSheet.learn

Class Variable Details

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joint_norm_fn

Function to use to compute the norm_total for each CF in each projection from a group to be normalized jointly.

Value:

param.Callable(default= compute_joint_norm_totals, doc= """
    Function to use to compute the norm_total for each CF in each
    projection from a group to be normalized jointly.""")