PopulationView

core.PopulationView.PopulationView(self, population, ranks, geometry=None)

Container representing a subset of neurons of a Population.

Attributes

Name	Description
attributes	Returns a list of attributes of the original population.
geometry	Geometry of the PopulationView (optional).
name	Returns the name of the original population.
parameters	Returns a list of constants of the original population.
population	Original (full) population.
ranks	Array of ranks in the PopulationView.
size	Size of the PopulationView.
targets	List of targets connected to the population.
variables	Returns a list of variables of the original population.

Methods

Name	Description
coordinates_from_rank	Returns the coordinates of a neuron based on its rank.
get	Returns current variable/parameter value.
rank_from_coordinates	Returns the rank of a neuron based on coordinates.
set	Updates the neurons’ variable/parameter values.
sum	Returns the array of weighted sums corresponding to the target::

coordinates_from_rank

core.PopulationView.PopulationView.coordinates_from_rank(rank, local=False)

Returns the coordinates of a neuron based on its rank.

When local is False (default), the coordinates are relative to the ORIGINAL population, not the PopulationView.

When local is True, the coordinates are interpreted relative to the geometry of the PopulationView if available. When you add two population views, the geometry is lost and the method will return an error.

The rank is relative to the original population. Iterate over len(pop) otherwise.

Parameters

Name	Type	Description	Default
rank		rank of the neuron in the original population	required
local		whether the coordinates are local to the PopulationView or not (default: False).	False

get

core.PopulationView.PopulationView.get(name)

Returns current variable/parameter value.

Parameters

Name	Type	Description	Default
name		name of the parameter/variable.	required

rank_from_coordinates

core.PopulationView.PopulationView.rank_from_coordinates(coord, local=False)

Returns the rank of a neuron based on coordinates.

When local is False (default), the coordinates are relative to the ORIGINAL population, not the PopulationView.

When local is True, the coordinates are interpreted relative to the geometry of the PopulationView if available. When you add two population views, the geometry is lost and the method will return an error.

The rank is relative to the original population. Iterate over len(pop) otherwise.

Parameters

Name	Type	Description	Default
coord		coordinate tuple, can be multidimensional.	required
local		whther the coordinates are local to the PopulationView or not (default: False).	False

set

core.PopulationView.PopulationView.set(value)

Updates the neurons’ variable/parameter values.

Parameters

Name	Type	Description	Default
value	dict	dictionary of parameters/variables to be updated for the corresponding subset of neurons. It can be a single value or a list/1D array of the same size as the PopulationView. .. code-block:: python >>> subpop = pop[0:5] >>> subpop.set( {‘tau’ : 20, ‘r’= np.random.rand(subpop.size) } ) .. warning:: If you modify the value of a global parameter, this will be the case for ALL neurons of the population, not only the subset.	required

sum

core.PopulationView.PopulationView.sum(target)

Returns the array of weighted sums corresponding to the target::

excitatory = pop.sum('exc')

For spiking networks, this is equivalent to accessing the conductances directly::

excitatory = pop.g_exc

If no incoming projection has the given target, the method returns zeros.

Parameters

Name	Type	Description	Default
target		the desired projection target. Note: it is not possible to distinguish the original population when the same target is used.	required