Merge pull request #8163 from dstansby/errbar-none-fmt

tacaswell · web-flow · commit b6f17f392591 · 2017-03-11T16:54:31.000-05:00
FIX: Plot errorbars when fmt == 'none'
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -2820,6 +2820,9 @@ def errorbar(self, x, y, yerr=None, xerr=None,
         fmt_style_kwargs = {k: v for k, v in
                             zip(('linestyle', 'marker', 'color'),
                                 _process_plot_format(fmt)) if v is not None}
+        if fmt == 'none':
+            # Remove alpha=0 color that _process_plot_format returns
+            fmt_style_kwargs.pop('color')
 
         if ('color' in kwargs or 'color' in fmt_style_kwargs or
                 ecolor is not None):
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -2454,6 +2454,18 @@ def test_errorbar_limits():
     ax.set_title('Errorbar upper and lower limits')
 
 
+@cleanup
+def test_errobar_nonefmt():
+    # Check that passing 'none' as a format still plots errorbars
+    x = np.arange(5)
+    y = np.arange(5)
+
+    plotline, _, barlines = plt.errorbar(x, y, xerr=1, yerr=1, fmt='none')
+    assert plotline is None
+    for errbar in barlines:
+        assert np.all(errbar.get_color() == mcolors.to_rgba('C0'))
+
+
 @image_comparison(baseline_images=['hist_stacked_stepfilled',
                                    'hist_stacked_stepfilled'])
 def test_hist_stacked_stepfilled():
