# expression_complexity function¶

(Shortest import: from brian2.parsing.sympytools import expression_complexity)

brian2.parsing.sympytools.expression_complexity(expr, complexity=None)[source]

Returns the complexity of an expression (either string or sympy)

The complexity is defined as 1 for each arithmetic operation except divide which is 2, and all other operations are 20. This can be overridden using the complexity argument.

Note: calling this on a statement rather than an expression is likely to lead to errors.

Parameters

expr: sympy.Expr or str :

The expression.

complexity: None or dict (optional) :

A dictionary mapping expression names to their complexity, to overwrite default behaviour.

Returns

complexity: int :

The complexity of the expression.