Common Types

Cell Identifiers and Indexes

The types defined below are used as identifiers for cells and members of cell-local collections.

class arbor.cell_member
cell_member(gid, index)

Construct a cell member with parameters gid and index for global identification of a cell-local item.

Items of type cell_member must:

  • be associated with a unique cell, identified by the member gid;
  • identify an item within a cell-local collection by the member index.

An example is uniquely identifying a synapse in the model. Each synapse has a post-synaptic cell (with gid), and an index into the set of synapses on the post-synaptic cell.

Lexographically ordered by gid, then index.


The global identifier of the cell.


The cell-local index of the item. Local indices for items within a particular cell-local collection should be zero-based and numbered contiguously.

An example of a cell member construction reads as follows:

import arbor

# construct
cmem = arbor.cell_member(0, 0)

# set gid and index
cmem.gid = 1
cmem.index = 42
class arbor.cell_kind

Enumeration used to identify the cell kind, used by the model to group equal kinds in the same cell group.


A cell with morphology described by branching 1D cable segments.


A leaky-integrate and fire neuron.


A proxy cell that generates spikes from a spike sequence provided by the user.


A proxy cell used for benchmarking.

An example for setting the cell kind reads as follows:

import arbor

kind = arbor.cell_kind.cable


class arbor.location

Construct a location specification with the branch id and the relative position on the branch ∈ [0.,1.], where 0. means proximal and 1. distal.


The id of the branch.


The relative position (from 0., proximal, to 1., distal) on the branch.