DOC: add note about different ba forms in tf2zpk #3307
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Changes Unknown when pulling 92c22cd on endolith:patch-3 into * on scipy:master*. |
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@Eric89GXL would you have time to check this in the next day or so? Would be nice to have this in for 0.14.0, and there's a lot of stuff left to do.... |
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Sure, I'll have a look. |
| @@ -244,7 +244,7 @@ def freqz(b, a=1, worN=None, whole=0, plot=None): | |||
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| def tf2zpk(b, a): | |||
| """Return zero, pole, gain (z,p,k) representation from a numerator, | |||
| r"""Return zero, pole, gain (z,p,k) representation from a numerator, | |||
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I'm just curious, why do we need the r here?
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Because there are \s in the docstring, and with 'r' (which means "raw string") those get interpreted as special characters.
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Ahh, so just less needing to do \\. Makes sense, thanks.
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yeah, http://legacy.python.org/dev/peps/pep-0257/ says
For consistency, always use """triple double quotes""" around docstrings. Use r"""raw triple double quotes""" if you use any backslashes in your docstrings.
but there was some controversy last time I did it? some script overwrites it or something? but then that got merged anyway so I don't know.
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Not AFAIK, I just wanted to know so I could pick up that tip
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Oh you're saying that there was some controversy, not asking if there was... I wonder if the docstring code gets angry or something.
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The docstring machinery won't complain. There's a preference to have as little LaTeX as possible and keep docstrings readable in a terminal, maybe it was about that. In this case it's still understandable though (at least for me), so I don't really mind.
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oh here it is: #498 (comment)
guess it doesn't matter though, because that was merged and then pv recommended doing it later: #2777 (comment)
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Yeah, shouldn't matter much. The doc editor became much less important over time, and anyway could be fixed if needed.
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I looked through it, and LGTM. |
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actually I should have added examples too, but if you want to merge it I can do those in a different PR |
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Let's merge this PR as is, then we're sure it goes into 0.14.0. Examples of course welcome. |
DOC: add note about different ba forms in tf2zpk
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Thanks both! |
of course someone should confirm that what I wrote is actually true...
Feel free to suggest different wordings.
For comparison, matlab has 2 different functions:
tf2zpfor s and positive z, andtf2zpkfor z^-1. Matlab also has thetffunction, which has a{'s', 'z', 'z^-1'}parameter. A parameter like that should probably be added to scipy'stf2zpkfunction? I think that's more usable than creating a separatetf2zpfunction (do mostly the same thing, hard to remember which is which). But for now I am just documenting the discrepancy.