Skip to content

matplotlib dev: What happened to figure.dpi ? #19928

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

Jump to bottom
Closed
pllim opened this issue Apr 9, 2021 · 8 comments
Closed

matplotlib dev: What happened to figure.dpi ? #19928

pllim opened this issue Apr 9, 2021 · 8 comments

Comments

@pllim
Copy link

pllim commented Apr 9, 2021 •
edited
Loading

This morning, we got a new error testing against matplotlib dev. Example log at https://app.circleci.com/pipelines/github/astropy/astropy/4691/workflows/582b72af-3420-4af5-a185-f0e41601edfd/jobs/86623

_______________________ test_no_numpy_warnings[contours] _______________________

ignore_matplotlibrc = None
tmpdir = local('/tmp/pytest-of-root/pytest-0/test_no_numpy_warnings_contour0')
grid_type = 'contours'

    @pytest.mark.parametrize('grid_type', ['lines', 'contours'])
    def test_no_numpy_warnings(ignore_matplotlibrc, tmpdir, grid_type):
        ax = plt.subplot(1, 1, 1, projection=WCS(TARGET_HEADER))
        ax.imshow(np.zeros((100, 200)))
        ax.coords.grid(color='white', grid_type=grid_type)
    
        with pytest.warns(None) as warning_lines:
>           plt.savefig(tmpdir.join('test.png').strpath)

../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/astropy/visualization/wcsaxes/tests/test_misc.py:80: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/pyplot.py:956: in savefig
    fig.canvas.draw_idle()   # need this if 'transparent=True' to reset colors
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/backend_bases.py:2058: in draw_idle
    self.draw(*args, **kwargs)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/backends/backend_agg.py:406: in draw
    self.figure.draw(self.renderer)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/artist.py:74: in draw_wrapper
    result = draw(artist, renderer, *args, **kwargs)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/artist.py:51: in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/figure.py:2727: in draw
    renderer, self, artists, self.suppressComposite)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/image.py:132: in _draw_list_compositing_images
    a.draw(renderer)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/astropy/visualization/wcsaxes/core.py:459: in draw
    super().draw(renderer, **kwargs)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/artist.py:51: in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/_api/deprecation.py:421: in wrapper
    return func(*inner_args, **inner_kwargs)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/axes/_base.py:3102: in draw
    mimage._draw_list_compositing_images(renderer, self, artists)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/image.py:132: in _draw_list_compositing_images
    a.draw(renderer)
../../.tox/py37-test-image-mpldev/lib/python3.7/site-packages/matplotlib/artist.py:51: in draw_wrapper
    return draw(artist, renderer, *args, **kwargs)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <matplotlib.collections.PathCollection object at 0x7f51ca1ac128>
renderer = <matplotlib.backends.backend_agg.RendererAgg object at 0x7f51cc0a0ef0>

    @artist.allow_rasterization
    def draw(self, renderer):
>       self.set_sizes(self._sizes, self.figure.dpi)
E       AttributeError: 'NoneType' object has no attribute 'dpi'

bisect attempt

d49696a is the first bad commit

commit d49696aba62820ce4bab41ae4a8508743e39a0e4
Author: Jody Klymak <...>
Date:   Sun Mar 14 14:08:50 2021 -0700

    New doc gallery for plot_types

Update: I don't think this is true actually... I have no idea what is going on

I think I traced it to https://github.com/astropy/astropy/blob/796b585f989319b766979df2110e0b4fa94a43a1/astropy/visualization/mpl_style.py#L63 . However, I am not sure if I should simply remove this setting or there is a new way to set it. Any advise would be greatly appreciated. Thanks!

# Version 1 astropy plotting style for matplotlib
astropy_mpl_style_1 = {
    # ...
    # Other
    'savefig.dpi': 72,
}
@pllim

This comment has been minimized.

Sign in to view
@pllim
Copy link
Author

pllim commented Apr 9, 2021

Update: Okay, I did manage to bisect and git said it is #19703 . I can't say I understand the details enough to formulate a fix based on this info. I might also have been bisecting it wrong so you can double check. Here are my scripts:

run_me.sh:

#!/bin/sh

python run_me.py

run_me.py:

import matplotlib.pyplot as plt
import numpy as np

from astropy.io import fits
from astropy.wcs import WCS

TARGET_HEADER = fits.Header.fromstring("""
NAXIS   =                    2
NAXIS1  =                  200
NAXIS2  =                  100
CTYPE1  = 'RA---MOL'
CRPIX1  =                  500
CRVAL1  =                180.0
CDELT1  =                 -0.4
CUNIT1  = 'deg     '
CTYPE2  = 'DEC--MOL'
CRPIX2  =                  400
CRVAL2  =                  0.0
CDELT2  =                  0.4
CUNIT2  = 'deg     '
COORDSYS= 'icrs    '
""", sep='\n')


def run():
    ax = plt.subplot(1, 1, 1, projection=WCS(TARGET_HEADER))
    ax.imshow(np.zeros((100, 200)))
    ax.coords.grid(color='white', grid_type='contours')

    plt.savefig('test.png')


if __name__ == '__main__':
    run()

@pllim pllim mentioned this issue Apr 9, 2021
Closed
1 task
@jklymak
Copy link
Member

jklymak commented Apr 9, 2021

It is pretty hard to see how #19703 could have caused any downstream issues since it doesn't change anything user facing, except to add a new style.

I'm not convinced this is Matplotlib's issue:

import matplotlib.pyplot as plt
import numpy as np

ax = plt.subplot(1, 1, 1, projection='polar')
ax.imshow(np.zeros((100, 200)))

plt.savefig('test.png')

works fine on master.

@pllim
Copy link
Author

pllim commented Apr 9, 2021

Indeed, I couldn't reproduce this if I take out the astropy stuff and seems to only affect contours. I'll have to defer to the expertise of @astrofrog and @Cadair here.

@jklymak
Copy link
Member

jklymak commented Apr 9, 2021

I'm going to close for now because this has gotten a bit confusing, but feel free to open a new issue if you narrow it down to something we broke. Thanks again for testing us early on!

@jklymak jklymak closed this as completed Apr 9, 2021
@tacaswell
Copy link
Member

E AttributeError: 'NoneType' object has no attribute 'dpi'

The issue is not that figure.dpi has gone away, the issue is that self.figure is None

@jklymak
Copy link
Member

jklymak commented Apr 9, 2021

Is this possibly the add_axes issue? #19496, #18364? and somehow this axes is not being added to the figure?

@pllim
Copy link
Author

pllim commented Apr 10, 2021

I think I did the bisect wrong. It gives me different answer depending on where I set the "good". I can't seem to find an option that is equivalent to -m 1 for cherry-pick.

The only thing I am sure of is that this is caused by something that got merged in the past 24-36 hours (as of writing). Let's just wait for Tom Robitaille and Stuart Mumford's inputs. I don't usually work with that part of the code, and I need to move on to other work. Thanks, everyone!

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees
No one assigned
Labels
None yet
Projects
None yet
Milestone
No milestone
Development

No branches or pull requests
3 participants
@tacaswell @jklymak @pllim