[SciPy-User] Strange behaviour of scipy.interpolate.interp1d in with kind="zero"

[Propadovic Nenad]

Hello Oleksandr,

thank you for the swift answer.

I think we can settle for an untreated edge case and/or an inconsistency.
The values at times 0.004, 0.008, 0.012, 0.016 are exactly what I expect,
after all: the exact values that the original signal at the exact points in
time.

I will file a bug, as you proposed.

Regards,

Nenad


> Hi Nenad:
>
> This probably how the kind="zero" is implemented (uses a constant value
> from the left side of the interval) and since in your case you do not have
> any data to the right of the point, it is never used.
>
> Maybe it could be called bug.... (You could try to submit an issue on
> github)
>
> Apparently, now for it to work as you want, you would need to extend your
> sig a bit:
>
> import numpy
> from scipy.interpolate import interp1d
> t = numpy.array([0.000, 0.004, 0.008, 0.012, 0.016, 0.02, 0.03])
> sig = numpy.array([0, 1, 2, 3, 4, 5, 6])
> t_new = numpy.array([0.0, 0.001, 0.003, 0.004, 0.008, 0.012, 0.016, 0.0196,
> 0.02])
> f = interp1d(t, sig, kind='zero')
> s_resampled = f(t_new)
> print(s_resampled)
> [ 0.  0.  0.  1.  2.  3.  4.  4.  5.]
>
>
> Cheers
>
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