Oh, wow. I never noticed that before. Yeah, if I state that retstep=True, then I am coding my handling to expect two values to be returned, not 1. I think it should be nan, but I could also agree with zero. It should definitely remain a float value, though. Cheers! Ben Root On Tue, Jan 13, 2015 at 10:15 AM, Jaime Fernández del Río < jaime.frio@gmail.com> wrote:

While working on something else, I realized that linspace is not handling requests for returning the sampling spacing consistently:

np.linspace(0, 1, 3, retstep=True) (array([ 0. , 0.5, 1. ]), 0.5) np.linspace(0, 1, 1, retstep=True) array([ 0.]) np.linspace(0, 1, 0, retstep=True) array([], dtype=float64)

Basically, retstep is ignored if the number of samples is 0 or 1. One could argue that it makes sense, because those sequences do not have a spacing defined. But at the very least it should be documented as doing so, and the following inconsistency removed:

np.linspace(0, 1, 1, endpoint=True, retstep=True) array([ 0.]) np.linspace(0, 1, 1, endpoint=False, retstep=True) (array([ 0.]), 1.0)

I am personally inclined to think that if a step is requested, then a step should be returned, and if it cannot be calculated in a reasonable manner, then a placeholder such as None, nan, 0 or stop - start should be returned.

What does the collective wisdom think is the best approach for this?

Jaime

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