nlcpy.select

nlcpy.select(condlist, choicelist, default=0)[source]

Returns an array drawn from elements in choicelist, depending on conditions.

Parameters

condlistlist of bool ndarrays: The list of conditions which determine from which array in choicelist the output elements are taken. When multiple conditions are satisfied, the first one encountered in condlist is used.
choicelistlist of ndarrays: The list of arrays from which the output elements are taken. It has to be of the same length as condlist.
defaultscalar, optional: The element inserted in output when all conditions evaluate to False.

Returns

outputndarray: The output at position m is the m-th element of the array in choicelist where the m-th element of the corresponding array in condlist is True.

See also

where: Returns elements chosen from x or y depending on condition.
take: Takes elements from an array along an axis.
diag: Extracts a diagonal or construct a diagonal array.
diagonal: Returns specified diagonals.

Examples

>>> import nlcpy as vp
>>> x = vp.arange(10)
>>> condlist = [x<3, x>5]
>>> choicelist = [x, x**2]
>>> vp.select(condlist, choicelist)
array([ 0,  1,  2,  0,  0,  0, 36, 49, 64, 81])