Should numpy.sqrt(-1) return 1j rather than nan?

Fernando Perez at
Wed Oct 11 16:37:34 CDT 2006

On 10/11/06, Travis Oliphant <oliphant at> wrote:

> pearu at wrote:
> >Could sqrt(-1) made to return 1j again?
> >
> Not in NumPy.  But, in scipy it could.

Without taking sides on which way to go, I'd like to -1 the idea of a
difference in behavior between numpy and scipy.

IMHO, scipy should be within reason a strict superset of numpy.
Gratuitious differences in behavior like this one are going to drive
us all mad.

There are people who import scipy for everything, others distinguish
between numpy and scipy, others use numpy alone and at some point in
their life's code they do

import numpy as N -> import scipy as N

because they start needing stuff not in plain numpy.  Having different
APIs and behaviors appear there is, I think, a Seriously Bad Idea

Just my 1e-2j,



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