Skip to content

FIX: Handle inverted colorbar axes with extensions #22635

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

Merged
merged 1 commit into from
Mar 14, 2022
Merged

FIX: Handle inverted colorbar axes with extensions #22635

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
61 changes: 46 additions & 15 deletions lib/matplotlib/colorbar.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -417,6 +417,7 @@ def __init__(self, ax, mappable=None, *, cmap=None,
self._filled = filled
self.extendfrac = extendfrac
self.extendrect = extendrect
self._extend_patches = []
self.solids = None
self.solids_patches = []
self.lines = []
Expand Down Expand Up @@ -483,6 +484,11 @@ def __init__(self, ax, mappable=None, *, cmap=None,
setattr(self.ax, x, getattr(self, x))
# Set the cla function to the cbar's method to override it
self.ax.cla = self._cbar_cla
# Callbacks for the extend calculations to handle inverting the axis
self._extend_cid1 = self.ax.callbacks.connect(
"xlim_changed", self._do_extends)
self._extend_cid2 = self.ax.callbacks.connect(
"ylim_changed", self._do_extends)

@property
def locator(self):
Expand Down Expand Up @@ -598,17 +604,20 @@ def _draw_all(self):
# extensions:
self.vmin, self.vmax = self._boundaries[self._inside][[0, -1]]
# Compute the X/Y mesh.
X, Y, extendlen = self._mesh()
X, Y = self._mesh()
# draw the extend triangles, and shrink the inner axes to accommodate.
# also adds the outline path to self.outline spine:
self._do_extends(extendlen)

self._do_extends()
lower, upper = self.vmin, self.vmax
if self._long_axis().get_inverted():
# If the axis is inverted, we need to swap the vmin/vmax
lower, upper = upper, lower
if self.orientation == 'vertical':
self.ax.set_xlim(0, 1)
self.ax.set_ylim(self.vmin, self.vmax)
self.ax.set_ylim(lower, upper)
else:
self.ax.set_ylim(0, 1)
self.ax.set_xlim(self.vmin, self.vmax)
self.ax.set_xlim(lower, upper)

# set up the tick locators and formatters. A bit complicated because
# boundary norms + uniform spacing requires a manual locator.
Expand Down Expand Up @@ -661,12 +670,19 @@ def _add_solids_patches(self, X, Y, C, mappable):
patches.append(patch)
self.solids_patches = patches

def _do_extends(self, extendlen):
def _do_extends(self, ax=None):
"""
Add the extend tri/rectangles on the outside of the axes.

ax is unused, but required due to the callbacks on xlim/ylim changed
"""
# Clean up any previous extend patches
for patch in self._extend_patches:
patch.remove()
self._extend_patches = []
# extend lengths are fraction of the *inner* part of colorbar,
# not the total colorbar:
_, extendlen = self._proportional_y()
bot = 0 - (extendlen[0] if self._extend_lower() else 0)
top = 1 + (extendlen[1] if self._extend_upper() else 0)

Expand Down Expand Up @@ -708,12 +724,17 @@ def _do_extends(self, extendlen):
if self.orientation == 'horizontal':
xy = xy[:, ::-1]
# add the patch
color = self.cmap(self.norm(self._values[0]))
val = -1 if self._long_axis().get_inverted() else 0
color = self.cmap(self.norm(self._values[val]))
patch = mpatches.PathPatch(
mpath.Path(xy), facecolor=color, linewidth=0,
antialiased=False, transform=self.ax.transAxes,
hatch=hatches[0], clip_on=False)
hatch=hatches[0], clip_on=False,
# Place it right behind the standard patches, which is
# needed if we updated the extends
zorder=np.nextafter(self.ax.patch.zorder, -np.inf))
self.ax.add_patch(patch)
self._extend_patches.append(patch)
if self._extend_upper():
if not self.extendrect:
# triangle
Expand All @@ -724,12 +745,17 @@ def _do_extends(self, extendlen):
if self.orientation == 'horizontal':
xy = xy[:, ::-1]
# add the patch
color = self.cmap(self.norm(self._values[-1]))
val = 0 if self._long_axis().get_inverted() else -1
color = self.cmap(self.norm(self._values[val]))
patch = mpatches.PathPatch(
mpath.Path(xy), facecolor=color,
linewidth=0, antialiased=False,
transform=self.ax.transAxes, hatch=hatches[-1], clip_on=False)
transform=self.ax.transAxes, hatch=hatches[-1], clip_on=False,
# Place it right behind the standard patches, which is
# needed if we updated the extends
zorder=np.nextafter(self.ax.patch.zorder, -np.inf))
self.ax.add_patch(patch)
self._extend_patches.append(patch)
return

def add_lines(self, *args, **kwargs):
Expand Down Expand Up @@ -1049,6 +1075,9 @@ def remove(self):
self.mappable.callbacks.disconnect(self.mappable.colorbar_cid)
self.mappable.colorbar = None
self.mappable.colorbar_cid = None
# Remove the extension callbacks
self.ax.callbacks.disconnect(self._extend_cid1)
self.ax.callbacks.disconnect(self._extend_cid2)

try:
ax = self.mappable.axes
Expand Down Expand Up @@ -1151,7 +1180,7 @@ def _mesh(self):
These are scaled between vmin and vmax, and already handle colorbar
orientation.
"""
y, extendlen = self._proportional_y()
y, _ = self._proportional_y()
# Use the vmin and vmax of the colorbar, which may not be the same
# as the norm. There are situations where the colormap has a
# narrower range than the colorbar and we want to accommodate the
Expand All @@ -1172,9 +1201,9 @@ def _mesh(self):
self._y = y
X, Y = np.meshgrid([0., 1.], y)
if self.orientation == 'vertical':
return (X, Y, extendlen)
return (X, Y)
else:
return (Y, X, extendlen)
return (Y, X)

def _forward_boundaries(self, x):
# map boundaries equally between 0 and 1...
Expand Down Expand Up @@ -1322,11 +1351,13 @@ def _get_extension_lengths(self, frac, automin, automax, default=0.05):

def _extend_lower(self):
"""Return whether the lower limit is open ended."""
return self.extend in ('both', 'min')
minmax = "max" if self._long_axis().get_inverted() else "min"
return self.extend in ('both', minmax)

def _extend_upper(self):
"""Return whether the upper limit is open ended."""
return self.extend in ('both', 'max')
minmax = "min" if self._long_axis().get_inverted() else "max"
return self.extend in ('both', minmax)

def _long_axis(self):
"""Return the long axis"""
Expand Down
24 changes: 24 additions & 0 deletions lib/matplotlib/tests/test_colorbar.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -124,6 +124,30 @@ def test_colorbar_extension_length():
_colorbar_extension_length('proportional')


@pytest.mark.parametrize("orientation", ["horizontal", "vertical"])
@pytest.mark.parametrize("extend,expected", [("min", (0, 0, 0, 1)),
("max", (1, 1, 1, 1)),
("both", (1, 1, 1, 1))])
def test_colorbar_extension_inverted_axis(orientation, extend, expected):
"""Test extension color with an inverted axis"""
data = np.arange(12).reshape(3, 4)
fig, ax = plt.subplots()
cmap = plt.get_cmap("viridis").with_extremes(under=(0, 0, 0, 1),
over=(1, 1, 1, 1))
im = ax.imshow(data, cmap=cmap)
cbar = fig.colorbar(im, orientation=orientation, extend=extend)
if orientation == "horizontal":
cbar.ax.invert_xaxis()
else:
cbar.ax.invert_yaxis()
assert cbar._extend_patches[0].get_facecolor() == expected
if extend == "both":
assert len(cbar._extend_patches) == 2
assert cbar._extend_patches[1].get_facecolor() == (0, 0, 0, 1)
else:
assert len(cbar._extend_patches) == 1


@pytest.mark.parametrize('use_gridspec', [True, False])
@image_comparison(['cbar_with_orientation',
'cbar_locationing',
Expand Down