[SciPy-Dev] Proposed API change for some functions in scipy.signal

[Phillip Feldman]

This is an excellent change!

What does the code do if the caller specifies both `fs` and `nyq`?

On Wed, Aug 30, 2017 at 10:22 PM, Warren Weckesser <
warren.weckesser at gmail.com> wrote:

> I've been using quite a few of the functions in scipy.signal recently, and
> I've been reminded of some of the quirks of the API. I have submitted a
> pull request to clean up one of those quirks.
>
> In the new pull request, I have added the argument 'fs' (the sampling
> frequency) to the following functions:  firwin, firwin2, firls, and remez.
> For firwin, firwin2 and firls, the new argument replaces 'nyq', and for
> remez, it replaces 'Hz'.  This makes these functions consistent with the
> other functions in which the sampling frequency is specified using 'fs':
> periodogram, welch, csd, coherence, spectrogram, stft, and istft. 'fs', or
> in LaTeX, $f_s$, is common notation for the sampling frequency in the DSP
> literature.
>
> In the pull request, the old argument is given a "soft" deprecation. That
> means the docstring says the argument is deprecated, but code to actually
> generate a DeprecationWarning has not been added yet.  I'm fine with adding
> that now, but some might prefer a relatively long and soft transition for
> these changes.  (Personally, I don't mind if they hang around for a while,
> but they should be gone by 2.0. :)
>
> I haven't changed the default value of the sampling frequency.  For the
> FIR filter design functions firls, firwin and firwin2, the default is
> nyq=1.0 (equivalent to fs=2), while for remez the default is Hz=1 (i.e.
> fs=1).  The functions that currently already use 'fs' all have the default
> fs=1. Changing the default for the FIR design functions would be a much
> more disruptive change.
>
> Comments here or on the pull request are welcome.
>
> P.S. I can see future pull requests in which 'fs' is added to functions
> that currently don't have an argument to specify the sampling frequency.
> I'm looking at you, freqz.
>
>
> _______________________________________________
> SciPy-Dev mailing list
> SciPy-Dev at python.org
> https://mail.python.org/mailman/listinfo/scipy-dev
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/scipy-dev/attachments/20170831/aac75a37/attachment.html>