Thanks to visit codestin.com
Credit goes to github.com

Skip to content

Added a test to default the value of Fs to 2 for Axes.specgram and ml… #12813

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 2 commits into from
Closed

Added a test to default the value of Fs to 2 for Axes.specgram and ml… #12813

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
2902b27
Added a test to default the value of Fs to 2 for Axes.specgram and ml…
m4laclypse Nov 15, 2018
d5c44c4
Update _axes.py
m4laclypse Nov 16, 2018
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions lib/matplotlib/axes/_axes.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7629,6 +7629,8 @@ def specgram(self, x, NFFT=None, Fs=None, Fc=None, detrend=None,
Fc = 0 # same default as in mlab._spectral_helper()
if noverlap is None:
noverlap = 128 # same default as in mlab.specgram()
if Fs is None:
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

As discussed in #9221 (comment), I think that Fs should remain None, and the underlying function made to do the right thing with None. This function should not be calculating frequencies, but should just take them from the frequency output of the spectral helper.

Sorry to be a pain, but I'm going to block on this. If you need more details to modify the PR, I will try and take a look later today.

Copy link
Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Then I'll try to change the PR so as to modify the docstring so that it matches the fact that the default value is None. I will try to do this asap.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Well, I think there is a problem with the code as well, but I don't think setting Fs=2 is the solution. We should be making to Fs from the freqs array where it is needed in the code (Fs=freqs[-1] * 2)

Fs = 2 # same default as in mlab.specgram()

if mode == 'complex':
raise ValueError('Cannot plot a complex specgram')
Expand Down
2 changes: 2 additions & 0 deletions lib/matplotlib/mlab.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1113,6 +1113,8 @@ def specgram(x, NFFT=None, Fs=None, detrend=None, window=None,
noverlap = 128 # default in _spectral_helper() is noverlap = 0
if NFFT is None:
NFFT = 256 # same default as in _spectral_helper()
if Fs is None:
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Fs is only passed through in this function. It's not used explicitly. Therefore, there is no need to set the default explicitly again here; and I thus prefer to not duplicate the default. It's different with NFFT because its value is used in the warning.

Fs = 2 # same default as in _spectral_helper()
if len(x) <= NFFT:
cbook._warn_external("Only one segment is calculated since parameter "
"NFFT (=%d) >= signal length (=%d)." %
Expand Down