numpy.piecewise()

x : ndarray

The input domain.

condlist : list of bool arrays

Each boolean array corresponds to a function in funclist. Wherever condlist[i] is True, funclist[i](x) is used as the output value.

Each boolean array in condlist selects a piece of x, and should therefore be of the same shape as x.

The length of condlist must correspond to that of funclist. If one extra function is given, i.e. if len(funclist) - len(condlist) == 1, then that extra function is the default value, used wherever all conditions are false.

funclist : list of callables, f(x,*args,**kw), or scalars

Each function is evaluated over x wherever its corresponding condition is True. It should take an array as input and give an array or a scalar value as output. If, instead of a callable, a scalar is provided then a constant function (lambda x: scalar) is assumed.

args : tuple, optional

Any further arguments given to piecewise are passed to the functions upon execution, i.e., if called piecewise(..., ..., 1, 'a'), then each function is called as f(x, 1, 'a').

kw : dict, optional

Keyword arguments used in calling piecewise are passed to the functions upon execution, i.e., if called piecewise(..., ..., lambda=1), then each function is called as f(x, lambda=1).