Package topo :: Package base :: Module projection :: Class SheetMask

Class SheetMask

An abstract class that defines a mask over a ProjectionSheet object.

This class is typically used for optimization, where mask indicates which neurons are active and should be processed further. A mask can also be used for lesion experiments, to specify which units should be kept inactive.

See the code for CFProjection and CFResponseFn to see how this class can be used to restrict the computation to only those neurons that the Mask lists as active.

Nested Classes

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Inherited from param.parameterized.Parameterized: __metaclass__

Instance Methods

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_get_data(self)

source code

_set_data(self, data)

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_get_sheet(self)

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_set_sheet(self, sheet)

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__init__(self, sheet=None, **params)
x.__init__(...) initializes x; see x.__class__.__doc__ for signature

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__and__(self, mask)

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__or__(self, mask)

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reset(self)
Initialize mask to default value (with no neurons masked out).

source code

calculate(self)
Calculate a new mask based on the activity of the sheet.

source code

update(self)
Update the current mask based on the current activity and a previous mask.

source code

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, script_repr, set_default, set_dynamic_time_fn, set_param, state_pop, state_push, verbose, warning

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

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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data = overridable_property(_get_data, _set_data, doc= ...
Ensure that whenever somebody accesses the data they are not None.

sheet = overridable_property(_get_sheet, _set_sheet)

name = <param.parameterized.String object at 0xa9c1e2c>
String identifier for this object.

Inherited from param.parameterized.Parameterized: print_level

Properties

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Inherited from object: __class__

Method Details

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init(self, sheet=None, **params)
(Constructor)

source code

x.__init__(...) initializes x; see x.__class__.__doc__ for signature

Overrides: object.__init__: (inherited documentation)

calculate(self)

source code

Calculate a new mask based on the activity of the sheet.

For instance, in an algorithm like LISSOM that is based on a process of feedforward activation followed by lateral settling, the calculation is done at the beginning of each iteration after the feedforward activity has been calculated.

Subclasses should override this method to compute some non-default mask.

update(self)

source code

Update the current mask based on the current activity and a previous mask.

Should be called only if calculate() has already been called since the last reset(); potentially faster to compute than redoing the entire calculate().

Subclasses should override this method to compute some non-default mask.

Class Variable Details

[hide private]

data

Ensure that whenever somebody accesses the data they are not None.

Value:

overridable_property(_get_data, _set_data, doc= """
    Ensure that whenever somebody accesses the data they are not None.""")

Class SheetMask

__init__(self, sheet=None, **params) (Constructor)

calculate(self)

update(self)

data

init(self, sheet=None, **params)
(Constructor)