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fit_annuli: plots=None renders all panels (can't disable via None) and leaks Matplotlib figures in loops

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
48/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Quiet
Tech stack
matplotlib, numpy, python
Domain
data-visualization

Research direction

Start in eddy/rotationmap.py at fit_annuli around line 534, then inspect plot_velocity_profiles, plot_model, and plot_model_residual around the referenced plotting code. Run the 30-call reproduction and compare plots=None, plots=[], and the documented options. Done means the plots argument behavior, figure lifecycle, and docstring agree without accumulating open figures.

Written by the indexing model from the issue text.

Description

Summary

In rotationmap.fit_annuli, the plots argument defaults to None, but None is
interpreted as "plot all panels" rather than "plot nothing". To suppress plotting you
have to pass plots=[], which is neither documented nor obvious. Because the plotting
helpers open figures without closing them, calling fit_annuli in a loop (e.g. a
Monte-Carlo over many maps) leaks a figure per call — triggering matplotlib's
More than 20 figures have been opened warning and growing memory unbounded.

Version

eddy 3.1.0, eddy/rotationmap.py.

Where

# eddy/rotationmap.py, fit_annuli, ~L534
plots = ['profiles', 'model', 'residual'] if plots is None else plots
plots = np.atleast_1d(plots)
if 'profiles' in plots:
    self.plot_velocity_profiles(rpnts=rpnts, velo=velo, dvelo=dvelo)
if 'model' in plots:
    self.plot_model(model=model)
if 'residual' in plots:
    self.plot_model_residual(model=model)

Each of plot_velocity_profiles / plot_model / plot_model_residual does
fig, ax = plt.subplots() (e.g. rotationmap.py:2321) and never closes the figure.

Reproduce

import matplotlib.pyplot as plt
# rmap = some rotationmap / momentmap with a fittable map
for i in range(30):
    rmap.fit_annuli(x0=0, y0=0, inc=inc, PA=PA, rbins=rbins,
                    fit_vrad=True, fix_vlsr=vlsr, returns='residual')  # plots=None
print(len(plt.get_fignums()))   # ~90 open figures (3 per call); RuntimeWarning fires at 20

Expected vs. actual

  • Expected: plots=None (the default) produces no plots — the conventional meaning of
    an optional plots/plot kwarg — and repeated calls do not accumulate figures.
  • Actual: plots=None renders all three panels every call, and the figures are never
    closed, so a loop leaks figures and eventually warns / risks OOM.

Secondary: docstring mismatch

The docstring says:

plots (Optional[list]): Plots to generate after the fitting. Can be either of 'model'
and 'residual'. Default is both.

But the code default is three panels including 'profiles', and 'profiles' is a
valid (undocumented) option.

Suggested fix (your call)

  • Treat a falsy plots (None / [] / False) as no plots; if plot-by-default is
    wanted, use an explicit default list instead of the None sentinel.
  • Close the figures after drawing (or return them) so loop callers don't leak — or gate
    plotting behind an explicit plot=True.
  • Update the docstring to list 'profiles' and state the actual default.

Workaround

Pass plots=[] to suppress plotting.

Dominant language
Python
Stars
23
Forks
10
Avg merge
28m
Merged PRs (30d)
1

Getting set up

First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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