numpy.sign

numpy.sign(x[, out]) = <ufunc 'sign'>

Returns an element-wise indication of the sign of a number.

The sign function returns -1 if x < 0, 0 if x==0, 1 if x > 0.

Parameters :

x : array_like

Input values.

Returns :

y : ndarray

The sign of x.

Examples

>>> np.sign([-5., 4.5])
array([-1.,  1.])
>>> np.sign(0)
0