from collections import namedtuple
import contextlib
from functools import cache, wraps
import inspect
from inspect import Signature, Parameter
import logging
from numbers import Number, Real
import re
import warnings
import numpy as np
import matplotlib as mpl
from . import _api, cbook
from .colors import BoundaryNorm
from .cm import ScalarMappable
from .path import Path
from .transforms import (BboxBase, Bbox, IdentityTransform, Transform, TransformedBbox,
TransformedPatchPath, TransformedPath)
_log = logging.getLogger(__name__)
def _prevent_rasterization(draw):
# We assume that by default artists are not allowed to rasterize (unless
# its draw method is explicitly decorated). If it is being drawn after a
# rasterized artist and it has reached a raster_depth of 0, we stop
# rasterization so that it does not affect the behavior of normal artist
# (e.g., change in dpi).
@wraps(draw)
def draw_wrapper(artist, renderer, *args, **kwargs):
if renderer._raster_depth == 0 and renderer._rasterizing:
# Only stop when we are not in a rasterized parent
# and something has been rasterized since last stop.
renderer.stop_rasterizing()
renderer._rasterizing = False
return draw(artist, renderer, *args, **kwargs)
draw_wrapper._supports_rasterization = False
return draw_wrapper
def allow_rasterization(draw):
"""
Decorator for Artist.draw method. Provides routines
that run before and after the draw call. The before and after functions
are useful for changing artist-dependent renderer attributes or making
other setup function calls, such as starting and flushing a mixed-mode
renderer.
"""
@wraps(draw)
def draw_wrapper(artist, renderer):
try:
if artist.get_rasterized():
if renderer._raster_depth == 0 and not renderer._rasterizing:
renderer.start_rasterizing()
renderer._rasterizing = True
renderer._raster_depth += 1
else:
if renderer._raster_depth == 0 and renderer._rasterizing:
# Only stop when we are not in a rasterized parent
# and something has be rasterized since last stop
renderer.stop_rasterizing()
renderer._rasterizing = False
if artist.get_agg_filter() is not None:
renderer.start_filter()
return draw(artist, renderer)
finally:
if artist.get_agg_filter() is not None:
renderer.stop_filter(artist.get_agg_filter())
if artist.get_rasterized():
renderer._raster_depth -= 1
if (renderer._rasterizing and artist.figure and
artist.figure.suppressComposite):
# restart rasterizing to prevent merging
renderer.stop_rasterizing()
renderer.start_rasterizing()
draw_wrapper._supports_rasterization = True
return draw_wrapper
def _finalize_rasterization(draw):
"""
Decorator for Artist.draw method. Needed on the outermost artist, i.e.
Figure, to finish up if the render is still in rasterized mode.
"""
@wraps(draw)
def draw_wrapper(artist, renderer, *args, **kwargs):
result = draw(artist, renderer, *args, **kwargs)
if renderer._rasterizing:
renderer.stop_rasterizing()
renderer._rasterizing = False
return result
return draw_wrapper
def _stale_axes_callback(self, val):
if self.axes:
self.axes.stale = val
_XYPair = namedtuple("_XYPair", "x y")
class _Unset:
def __repr__(self):
return "<UNSET>"
_UNSET = _Unset()
class Artist:
"""
Abstract base class for objects that render into a FigureCanvas.
Typically, all visible elements in a figure are subclasses of Artist.
"""
zorder = 0
def __init_subclass__(cls):
# Decorate draw() method so that all artists are able to stop
# rastrization when necessary. If the artist's draw method is already
# decorated (has a `_supports_rasterization` attribute), it won't be
# decorated.
if not hasattr(cls.draw, "_supports_rasterization"):
cls.draw = _prevent_rasterization(cls.draw)
# Inject custom set() methods into the subclass with signature and
# docstring based on the subclasses' properties.
if not hasattr(cls.set, '_autogenerated_signature'):
# Don't overwrite cls.set if the subclass or one of its parents
# has defined a set method set itself.
# If there was no explicit definition, cls.set is inherited from
# the hierarchy of auto-generated set methods, which hold the
# flag _autogenerated_signature.
return
cls.set = lambda self, **kwargs: Artist.set(self, **kwargs)
cls.set.__name__ = "set"
cls.set.__qualname__ = f"{cls.__qualname__}.set"
cls._update_set_signature_and_docstring()
_PROPERTIES_EXCLUDED_FROM_SET = [
'navigate_mode', # not a user-facing function
'figure', # changing the figure is such a profound operation
# that we don't want this in set()
'3d_properties', # cannot be used as a keyword due to leading digit
]
@classmethod
def _update_set_signature_and_docstring(cls):
"""
Update the signature of the set function to list all properties
as keyword arguments.
Property aliases are not listed in the signature for brevity, but
are still accepted as keyword arguments.
"""
cls.set.__signature__ = Signature(
[Parameter("self", Parameter.POSITIONAL_OR_KEYWORD),
*[Parameter(prop, Parameter.KEYWORD_ONLY, default=_UNSET)
for prop in ArtistInspector(cls).get_setters()
if prop not in Artist._PROPERTIES_EXCLUDED_FROM_SET]])
cls.set._autogenerated_signature = True
cls.set.__doc__ = (
"Set multiple properties at once.\n\n"
"Supported properties are\n\n"
+ kwdoc(cls))
def __init__(self):
self._stale = True
self.stale_callback = None
self._axes = None
self.figure = None
self._transform = None
self._transformSet = False
self._visible = True
self._animated = False
self._alpha = None
self.clipbox = None
self._clippath = None
self._clipon = True
self._label = ''
self._picker = None
self._rasterized = False
self._agg_filter = None
# Normally, artist classes need to be queried for mouseover info if and
# only if they override get_cursor_data.
self._mouseover = type(self).get_cursor_data != Artist.get_cursor_data
self._callbacks = cbook.CallbackRegistry(signals=["pchanged"])
try:
self.axes = None
except AttributeError:
# Handle self.axes as a read-only property, as in Figure.
pass
self._remove_method = None
self._url = None
self._gid = None
self._snap = None
self._sketch = mpl.rcParams['path.sketch']
self._path_effects = mpl.rcParams['path.effects']
self._sticky_edges = _XYPair([], [])
self._in_layout = True
def __getstate__(self):
d = self.__dict__.copy()
d['stale_callback'] = None
return d
def remove(self):
"""
Remove the artist from the figure if possible.
The effect will not be visible until the figure is redrawn, e.g.,
with `.FigureCanvasBase.draw_idle`. Call `~.axes.Axes.relim` to
update the axes limits if desired.
Note: `~.axes.Axes.relim` will not see collections even if the
collection was added to the axes with *autolim* = True.
Note: there is no support for removing the artist's legend entry.
"""
# There is no method to set the callback. Instead, the parent should
# set the _remove_method attribute directly. This would be a
# protected attribute if Python supported that sort of thing. The
# callback has one parameter, which is the child to be removed.
if self._remove_method is not None:
self._remove_method(self)
# clear stale callback
self.stale_callback = None
_ax_flag = False
if hasattr(self, 'axes') and self.axes:
# remove from the mouse hit list
self.axes._mouseover_set.discard(self)
self.axes.stale = True
self.axes = None # decouple the artist from the Axes
_ax_flag = True
if self.figure:
if not _ax_flag:
self.figure.stale = True
self.figure = None
else:
raise NotImplementedError('cannot remove artist')
# TODO: the fix for the collections relim problem is to move the
# limits calculation into the artist itself, including the property of
# whether or not the artist should affect the limits. Then there will
# be no distinction between axes.add_line, axes.add_patch, etc.
# TODO: add legend support
def have_units(self):
"""Return whether units are set on any axis."""
ax = self.axes
return ax and any(axis.have_units() for axis in ax._axis_map.values())
def convert_xunits(self, x):
"""
Convert *x* using the unit type of the xaxis.
If the artist is not contained in an Axes or if the xaxis does not
have units, *x* itself is returned.
"""
ax = getattr(self, 'axes', None)
if ax is None or ax.xaxis is None:
return x
return ax.xaxis.convert_units(x)
def convert_yunits(self, y):
"""
Convert *y* using the unit type of the yaxis.
If the artist is not contained in an Axes or if the yaxis does not
have units, *y* itself is returned.
"""
ax = getattr(self, 'axes', None)
if ax is None or ax.yaxis is None:
return y
return ax.yaxis.convert_units(y)
@property
def axes(self):
"""The `~.axes.Axes` instance the artist resides in, or *None*."""
return self._axes
@axes.setter
def axes(self, new_axes):
if (new_axes is not None and self._axes is not None
and new_axes != self._axes):
raise ValueError("Can not reset the axes. You are probably "
"trying to re-use an artist in more than one "
"Axes which is not supported")
self._axes = new_axes
if new_axes is not None and new_axes is not self:
self.stale_callback = _stale_axes_callback
@property
def stale(self):
"""
Whether the artist is 'stale' and needs to be re-drawn for the output
to match the internal state of the artist.
"""
return self._stale
@stale.setter
def stale(self, val):
self._stale = val
# if the artist is animated it does not take normal part in the
# draw stack and is not expected to be drawn as part of the normal
# draw loop (when not saving) so do not propagate this change
if self._animated:
return
if val and self.stale_callback is not None:
self.stale_callback(self, val)
def get_window_extent(self, renderer=None):
"""
Get the artist's bounding box in display space.
The bounding box' width and height are nonnegative.
Subclasses should override for inclusion in the bounding box
"tight" calculation. Default is to return an empty bounding
box at 0, 0.
Be careful when using this function, the results will not update
if the artist window extent of the artist changes. The extent
can change due to any changes in the transform stack, such as
changing the axes limits, the figure size, or the canvas used
(as is done when saving a figure). This can lead to unexpected
behavior where interactive figures will look fine on the screen,
but will save incorrectly.
"""
return Bbox([[0, 0], [0, 0]])
def get_tightbbox(self, renderer=None):
"""
Like `.Artist.get_window_extent`, but includes any clipping.
Parameters
----------
renderer : `~matplotlib.backend_bases.RendererBase` subclass, optional
renderer that will be used to draw the figures (i.e.
``fig.canvas.get_renderer()``)
Returns
-------
`.Bbox` or None
The enclosing bounding box (in figure pixel coordinates).
Returns None if clipping results in no intersection.
"""
bbox = self.get_window_extent(renderer)
if self.get_clip_on():
clip_box = self.get_clip_box()
if clip_box is not None:
bbox = Bbox.intersection(bbox, clip_box)
clip_path = self.get_clip_path()
if clip_path is not None and bbox is not None:
clip_path = clip_path.get_fully_transformed_path()
bbox = Bbox.intersection(bbox, clip_path.get_extents())
return bbox
def add_callback(self, func):
"""
Add a callback function that will be called whenever one of the
`.Artist`'s properties changes.
Parameters
----------
func : callable
The callback function. It must have the signature::
def func(artist: Artist) -> Any
where *artist* is the calling `.Artist`. Return values may exist
but are ignored.
Returns
-------
int
The observer id associated with the callback. This id can be
used for removing the callback with `.remove_callback` later.
See Also
--------
remove_callback
"""
# Wrapping func in a lambda ensures it can be connected multiple times
# and never gets weakref-gc'ed.
return self._callbacks.connect("pchanged", lambda: func(self))
def remove_callback(self, oid):
"""
Remove a callback based on its observer id.
See Also
--------
add_callback
"""
self._callbacks.disconnect(oid)
def pchanged(self):
"""
Call all of the registered callbacks.
This function is triggered internally when a property is changed.
See Also
--------
add_callback
remove_callback
"""
self._callbacks.process("pchanged")
def is_transform_set(self):
"""
Return whether the Artist has an explicitly set transform.
This is *True* after `.set_transform` has been called.
"""
return self._transformSet
def set_transform(self, t):
"""
Set the artist transform.
Parameters
----------
t : `~matplotlib.transforms.Transform`
"""
self._transform = t
self._transformSet = True
self.pchanged()
self.stale = True
def get_transform(self):
"""Return the `.Transform` instance used by this artist."""
if self._transform is None:
self._transform = IdentityTransform()
elif (not isinstance(self._transform, Transform)
and hasattr(self._transform, '_as_mpl_transform')):
self._transform = self._transform._as_mpl_transform(self.axes)
return self._transform
def get_children(self):
r"""Return a list of the child `.Artist`\s of this `.Artist`."""
return []
def _different_canvas(self, event):
"""
Check whether an *event* occurred on a canvas other that this artist's canvas.
If this method returns True, the event definitely occurred on a different
canvas; if it returns False, either it occurred on the same canvas, or we may
not have enough information to know.
Subclasses should start their definition of `contains` as follows::
if self._different_canvas(mouseevent):
return False, {}
# subclass-specific implementation follows
"""
return (getattr(event, "canvas", None) is not None and self.figure is not None
and event.canvas is not self.figure.canvas)
def contains(self, mouseevent):
"""
Test whether the artist contains the mouse event.
Parameters
----------
mouseevent : `~matplotlib.backend_bases.MouseEvent`
Returns
-------
contains : bool
Whether any values are within the radius.
details : dict
An artist-specific dictionary of details of the event context,
such as which points are contained in the pick radius. See the
individual Artist subclasses for details.
"""
inside, info = self._default_contains(mouseevent)
if inside is not None:
return inside, info
_log.warning("%r needs 'contains' method", self.__class__.__name__)
return False, {}
def pickable(self):
"""
Return whether the artist is pickable.
See Also
--------
set_picker, get_picker, pick
"""
return self.figure is not None and self._picker is not None
def pick(self, mouseevent):
"""
Process a pick event.
Each child artist will fire a pick event if *mouseevent* is over
the artist and the artist has picker set.
See Also
--------
set_picker, get_picker, pickable
"""
from .backend_bases import PickEvent # Circular import.
# Pick self
if self.pickable():
picker = self.get_picker()
if callable(picker):
inside, prop = picker(self, mouseevent)
else:
inside, prop = self.contains(mouseevent)
if inside:
PickEvent("pick_event", self.figure.canvas,
mouseevent, self, **prop)._process()
# Pick children
for a in self.get_children():
# make sure the event happened in the same Axes
ax = getattr(a, 'axes', None)
if (mouseevent.inaxes is None or ax is None
or mouseevent.inaxes == ax):
# we need to check if mouseevent.inaxes is None
# because some objects associated with an Axes (e.g., a
# tick label) can be outside the bounding box of the
# Axes and inaxes will be None
# also check that ax is None so that it traverse objects
# which do not have an axes property but children might
a.pick(mouseevent)
def set_picker(self, picker):
"""
Define the picking behavior of the artist.
Parameters
----------
picker : None or bool or float or callable
This can be one of the following:
- *None*: Picking is disabled for this artist (default).
- A boolean: If *True* then picking will be enabled and the
artist will fire a pick event if the mouse event is over
the artist.
- A float: If picker is a number it is interpreted as an
epsilon tolerance in points and the artist will fire
off an event if its data is within epsilon of the mouse
event. For some artists like lines and patch collections,
the artist may provide additional data to the pick event
that is generated, e.g., the indices of the data within
epsilon of the pick event
- A function: If picker is callable, it is a user supplied
function which determines whether the artist is hit by the
mouse event::
hit, props = picker(artist, mouseevent)
to determine the hit test. if the mouse event is over the
artist, return *hit=True* and props is a dictionary of
properties you want added to the PickEvent attributes.
"""
self._picker = picker
def get_picker(self):
"""
Return the picking behavior of the artist.
The possible values are described in `.set_picker`.
See Also
--------
set_picker, pickable, pick
"""
return self._picker
def get_url(self):
"""Return the url."""
return self._url
def set_url(self, url):
"""
Set the url for the artist.
Parameters
----------
url : str
"""
self._url = url
def get_gid(self):
"""Return the group id."""
return self._gid
def set_gid(self, gid):
"""
Set the (group) id for the artist.
Parameters
----------
gid : str
"""
self._gid = gid
def get_snap(self):
"""
Return the snap setting.
See `.set_snap` for details.
"""
if mpl.rcParams['path.snap']:
return self._snap
else:
return False
def set_snap(self, snap):
"""
Set the snapping behavior.
Snapping aligns positions with the pixel grid, which results in
clearer images. For example, if a black line of 1px width was
defined at a position in between two pixels, the resulting image
would contain the interpolated value of that line in the pixel grid,
which would be a grey value on both adjacent pixel positions. In
contrast, snapping will move the line to the nearest integer pixel
value, so that the resulting image will really contain a 1px wide
black line.
Snapping is currently only supported by the Agg and MacOSX backends.
Parameters
----------
snap : bool or None
Possible values:
- *True*: Snap vertices to the nearest pixel center.
- *False*: Do not modify vertex positions.
- *None*: (auto) If the path contains only rectilinear line
segments, round to the nearest pixel center.
"""
self._snap = snap
self.stale = True
def get_sketch_params(self):
"""
Return the sketch parameters for the artist.
Returns
-------
tuple or None
A 3-tuple with the following elements:
- *scale*: The amplitude of the wiggle perpendicular to the
source line.
- *length*: The length of the wiggle along the line.
- *randomness*: The scale factor by which the length is
shrunken or expanded.
Returns *None* if no sketch parameters were set.
"""
return self._sketch
def set_sketch_params(self, scale=None, length=None, randomness=None):
"""
Set the sketch parameters.
Parameters
----------
scale : float, optional
The amplitude of the wiggle perpendicular to the source
line, in pixels. If scale is `None`, or not provided, no
sketch filter will be provided.
length : float, optional
The length of the wiggle along the line, in pixels
(default 128.0)
randomness : float, optional
The scale factor by which the length is shrunken or
expanded (default 16.0)
The PGF backend uses this argument as an RNG seed and not as
described above. Using the same seed yields the same random shape.
.. ACCEPTS: (scale: float, length: float, randomness: float)
"""
if scale is None:
self._sketch = None
else:
self._sketch = (scale, length or 128.0, randomness or 16.0)
self.stale = True
def set_path_effects(self, path_effects):
"""
Set the path effects.
Parameters
----------
path_effects : list of `.AbstractPathEffect`
"""
self._path_effects = path_effects
self.stale = True
def get_path_effects(self):
return self._path_effects
def get_figure(self):
"""Return the `.Figure` instance the artist belongs to."""
return self.figure
def set_figure(self, fig):
"""
Set the `.Figure` instance the artist belongs to.
Parameters
----------
fig : `~matplotlib.figure.Figure`
"""
# if this is a no-op just return
if self.figure is fig:
return
# if we currently have a figure (the case of both `self.figure`
# and *fig* being none is taken care of above) we then user is
# trying to change the figure an artist is associated with which
# is not allowed for the same reason as adding the same instance
# to more than one Axes
if self.figure is not None:
raise RuntimeError("Can not put single artist in "
"more than one figure")
self.figure = fig
if self.figure and self.figure is not self:
self.pchanged()
self.stale = True
def set_clip_box(self, clipbox):
"""
Set the artist's clip `.Bbox`.
Parameters
----------
clipbox : `~matplotlib.transforms.BboxBase` or None
Will typically be created from a `.TransformedBbox`. For instance,
``TransformedBbox(Bbox([[0, 0], [1, 1]]), ax.transAxes)`` is the default
clipping for an artist added to an Axes.
"""
_api.check_isinstance((BboxBase, None), clipbox=clipbox)
if clipbox != self.clipbox:
self.clipbox = clipbox
self.pchanged()
self.stale = True
def set_clip_path(self, path, transform=None):
"""
Set the artist's clip path.
Parameters
----------
path : `~matplotlib.patches.Patch` or `.Path` or `.TransformedPath` or None
The clip path. If given a `.Path`, *transform* must be provided as
well. If *None*, a previously set clip path is removed.
transform : `~matplotlib.transforms.Transform`, optional
Only used if *path* is a `.Path`, in which case the given `.Path`
is converted to a `.TransformedPath` using *transform*.
Notes
-----
For efficiency, if *path* is a `.Rectangle` this method will set the
clipping box to the corresponding rectangle and set the clipping path
to ``None``.
For technical reasons (support of `~.Artist.set`), a tuple
(*path*, *transform*) is also accepted as a single positional
parameter.
.. ACCEPTS: Patch or (Path, Transform) or None
"""
from matplotlib.patches import Patch, Rectangle
success = False
if transform is None:
if isinstance(path, Rectangle):
self.clipbox = TransformedBbox(Bbox.unit(),
path.get_transform())
self._clippath = None
success = True
elif isinstance(path, Patch):
self._clippath = TransformedPatchPath(path)
success = True
elif isinstance(path, tuple):
path, transform = path
if path is None:
self._clippath = None
success = True
elif isinstance(path, Path):
self._clippath = TransformedPath(path, transform)
success = True
elif isinstance(path, TransformedPatchPath):
self._clippath = path
success = True
elif isinstance(path, TransformedPath):
self._clippath = path
success = True
if not success:
raise TypeError(
"Invalid arguments to set_clip_path, of type "
f"{type(path).__name__} and {type(transform).__name__}")
# This may result in the callbacks being hit twice, but guarantees they
# will be hit at least once.
self.pchanged()
self.stale = True
def get_alpha(self):
"""
Return the alpha value used for blending - not supported on all
backends.
"""
return self._alpha
def get_visible(self):
"""Return the visibility."""
return self._visible
def get_animated(self):
"""Return whether the artist is animated."""
return self._animated
def get_in_layout(self):
"""
Return boolean flag, ``True`` if artist is included in layout
calculations.
E.g. :ref:`constrainedlayout_guide`,
`.Figure.tight_layout()`, and
``fig.savefig(fname, bbox_inches='tight')``.
"""
return self._in_layout
def _fully_clipped_to_axes(self):
"""
Return a boolean flag, ``True`` if the artist is clipped to the Axes
and can thus be skipped in layout calculations. Requires `get_clip_on`
is True, one of `clip_box` or `clip_path` is set, ``clip_box.extents``
is equivalent to ``ax.bbox.extents`` (if set), and ``clip_path._patch``
is equivalent to ``ax.patch`` (if set).
"""
# Note that ``clip_path.get_fully_transformed_path().get_extents()``
# cannot be directly compared to ``axes.bbox.extents`` because the
# extents may be undefined (i.e. equivalent to ``Bbox.null()``)
# before the associated artist is drawn, and this method is meant
# to determine whether ``axes.get_tightbbox()`` may bypass drawing
clip_box = self.get_clip_box()
clip_path = self.get_clip_path()
return (self.axes is not None
and self.get_clip_on()
and (clip_box is not None or clip_path is not None)
and (clip_box is None
or np.all(clip_box.extents == self.axes.bbox.extents))
and (clip_path is None
or isinstance(clip_path, TransformedPatchPath)
and clip_path._patch is self.axes.patch))
def get_clip_on(self):
"""Return whether the artist uses clipping."""
return self._clipon
def get_clip_box(self):
"""Return the clipbox."""
return self.clipbox
def get_clip_path(self):
"""Return the clip path."""
return self._clippath
def get_transformed_clip_path_and_affine(self):
"""
Return the clip path with the non-affine part of its
transformation applied, and the remaining affine part of its
transformation.
"""
if self._clippath is not None:
return self._clippath.get_transformed_path_and_affine()
return None, None
def set_clip_on(self, b):
"""
Set whether the artist uses clipping.
When False, artists will be visible outside the Axes which
can lead to unexpected results.
Parameters
----------
b : bool
"""
self._clipon = b
# This may result in the callbacks being hit twice, but ensures they
# are hit at least once
self.pchanged()
self.stale = True
def _set_gc_clip(self, gc):
"""Set the clip properly for the gc."""
if self._clipon:
if self.clipbox is not None:
gc.set_clip_rectangle(self.clipbox)
gc.set_clip_path(self._clippath)
else:
gc.set_clip_rectangle(None)
gc.set_clip_path(None)
def get_rasterized(self):
"""Return whether the artist is to be rasterized."""
return self._rasterized
def set_rasterized(self, rasterized):
"""
Force rasterized (bitmap) drawing for vector graphics output.
Rasterized drawing is not supported by all artists. If you try to
enable this on an artist that does not support it, the command has no
effect and a warning will be issued.
This setting is ignored for pixel-based output.
See also :doc:`/gallery/misc/rasterization_demo`.
Parameters
----------
rasterized : bool
"""
supports_rasterization = getattr(self.draw,
"_supports_rasterization", False)
if rasterized and not supports_rasterization:
_api.warn_external(f"Rasterization of '{self}' will be ignored")
self._rasterized = rasterized
def get_agg_filter(self):
"""Return filter function to be used for agg filter."""
return self._agg_filter
def set_agg_filter(self, filter_func):
"""
Set the agg filter.
Parameters
----------
filter_func : callable
A filter function, which takes a (m, n, depth) float array
and a dpi value, and returns a (m, n, depth) array and two
offsets from the bottom left corner of the image
.. ACCEPTS: a filter function, which takes a (m, n, 3) float array
and a dpi value, and returns a (m, n, 3) array and two offsets
from the bottom left corner of the image
"""
self._agg_filter = filter_func
self.stale = True
def draw(self, renderer):
"""
Draw the Artist (and its children) using the given renderer.
This has no effect if the artist is not visible (`.Artist.get_visible`
returns False).
Parameters
----------
renderer : `~matplotlib.backend_bases.RendererBase` subclass.
Notes
-----
This method is overridden in the Artist subclasses.
"""
if not self.get_visible():
return
self.stale = False
def set_alpha(self, alpha):
"""
Set the alpha value used for blending - not supported on all backends.
Parameters
----------
alpha : scalar or None
*alpha* must be within the 0-1 range, inclusive.
"""
if alpha is not None and not isinstance(alpha, Real):
raise TypeError(
f'alpha must be numeric or None, not {type(alpha)}')
if alpha is not None and not (0 <= alpha <= 1):
raise ValueError(f'alpha ({alpha}) is outside 0-1 range')
if alpha != self._alpha:
self._alpha = alpha
self.pchanged()
self.stale = True
def _set_alpha_for_array(self, alpha):
"""
Set the alpha value used for blending - not supported on all backends.
Parameters
----------
alpha : array-like or scalar or None
All values must be within the 0-1 range, inclusive.
Masked values and nans are not supported.
"""
if isinstance(alpha, str):
raise TypeError("alpha must be numeric or None, not a string")
if not np.iterable(alpha):
Artist.set_alpha(self, alpha)
return
alpha = np.asarray(alpha)
if not (0 <= alpha.min() and alpha.max() <= 1):
raise ValueError('alpha must be between 0 and 1, inclusive, '
f'but min is {alpha.min()}, max is {alpha.max()}')
self._alpha = alpha
self.pchanged()
self.stale = True
def set_visible(self, b):
"""
Set the artist's visibility.
Parameters
----------
b : bool
"""
if b != self._visible:
self._visible = b
self.pchanged()
self.stale = True
def set_animated(self, b):
"""
Set whether the artist is intended to be used in an animation.
If True, the artist is excluded from regular drawing of the figure.
You have to call `.Figure.draw_artist` / `.Axes.draw_artist`
explicitly on the artist. This approach is used to speed up animations
using blitting.
See also `matplotlib.animation` and
:ref:`blitting`.
Parameters
----------
b : bool
"""
if self._animated != b:
self._animated = b
self.pchanged()
def set_in_layout(self, in_layout):
"""
Set if artist is to be included in layout calculations,
E.g. :ref:`constrainedlayout_guide`,
`.Figure.tight_layout()`, and
``fig.savefig(fname, bbox_inches='tight')``.
Parameters
----------
in_layout : bool
"""
self._in_layout = in_layout
def get_label(self):
"""Return the label used for this artist in the legend."""
return self._label
def set_label(self, s):
"""
Set a label that will be displayed in the legend.
Parameters
----------
s : object
*s* will be converted to a string by calling `str`.
"""
label = str(s) if s is not None else None
if label != self._label:
self._label = label
self.pchanged()
self.stale = True
def get_zorder(self):
"""Return the artist's zorder."""
return self.zorder
def set_zorder(self, level):
"""
Set the zorder for the artist. Artists with lower zorder
values are drawn first.
Parameters
----------
level : float
"""
if level is None:
level = self.__class__.zorder
if level != self.zorder:
self.zorder = level
self.pchanged()
self.stale = True
@property
def sticky_edges(self):
"""
``x`` and ``y`` sticky edge lists for autoscaling.
When performing autoscaling, if a data limit coincides with a value in
the corresponding sticky_edges list, then no margin will be added--the
view limit "sticks" to the edge. A typical use case is histograms,
where one usually expects no margin on the bottom edge (0) of the
histogram.
Moreover, margin expansion "bumps" against sticky edges and cannot
cross them. For example, if the upper data limit is 1.0, the upper
view limit computed by simple margin application is 1.2, but there is a
sticky edge at 1.1, then the actual upper view limit will be 1.1.
This attribute cannot be assigned to; however, the ``x`` and ``y``
lists can be modified in place as needed.
Examples
--------
>>> artist.sticky_edges.x[:] = (xmin, xmax)
>>> artist.sticky_edges.y[:] = (ymin, ymax)
"""
return self._sticky_edges
def update_from(self, other):
"""Copy properties from *other* to *self*."""
self._transform = other._transform
self._transformSet = other._transformSet
self._visible = other._visible
self._alpha = other._alpha
self.clipbox = other.clipbox
self._clipon = other._clipon
self._clippath = other._clippath
self._label = other._label
self._sketch = other._sketch
self._path_effects = other._path_effects
self.sticky_edges.x[:] = other.sticky_edges.x.copy()
self.sticky_edges.y[:] = other.sticky_edges.y.copy()
self.pchanged()
self.stale = True
def properties(self):
"""Return a dictionary of all the properties of the artist."""
return ArtistInspector(self).properties()
def _update_props(self, props, errfmt):
"""
Helper for `.Artist.set` and `.Artist.update`.
*errfmt* is used to generate error messages for invalid property
names; it gets formatted with ``type(self)`` and the property name.
"""
ret = []
with cbook._setattr_cm(self, eventson=False):
for k, v in props.items():
# Allow attributes we want to be able to update through
# art.update, art.set, setp.
if k == "axes":
ret.append(setattr(self, k, v))
else:
func = getattr(self, f"set_{k}", None)
if not callable(func):
raise AttributeError(
errfmt.format(cls=type(self), prop_name=k))
ret.append(func(v))
if ret:
self.pchanged()
self.stale = True
return ret
def update(self, props):
"""
Update this artist's properties from the dict *props*.
Parameters
----------
props : dict
"""
return self._update_props(
props, "{cls.__name__!r} object has no property {prop_name!r}")
def _internal_update(self, kwargs):
"""
Update artist properties without prenormalizing them, but generating
errors as if calling `set`.
The lack of prenormalization is to maintain backcompatibility.
"""
return self._update_props(
kwargs, "{cls.__name__}.set() got an unexpected keyword argument "
"{prop_name!r}")
def set(self, **kwargs):
# docstring and signature are auto-generated via
# Artist._update_set_signature_and_docstring() at the end of the
# module.
return self._internal_update(cbook.normalize_kwargs(kwargs, self))
@contextlib.contextmanager
def _cm_set(self, **kwargs):
"""
`.Artist.set` context-manager that restores original values at exit.
"""
orig_vals = {k: getattr(self, f"get_{k}")() for k in kwargs}
try:
self.set(**kwargs)
yield
finally:
self.set(**orig_vals)
def findobj(self, match=None, include_self=True):
"""
Find artist objects.
Recursively find all `.Artist` instances contained in the artist.
Parameters
----------
match
A filter criterion for the matches. This can be
- *None*: Return all objects contained in artist.
- A function with signature ``def match(artist: Artist) -> bool``.
The result will only contain artists for which the function
returns *True*.
- A class instance: e.g., `.Line2D`. The result will only contain
artists of this class or its subclasses (``isinstance`` check).
include_self : bool
Include *self* in the list to be checked for a match.
Returns
-------
list of `.Artist`
"""
if match is None: # always return True
def matchfunc(x):
return True
elif isinstance(match, type) and issubclass(match, Artist):
def matchfunc(x):
return isinstance(x, match)
elif callable(match):
matchfunc = match
else:
raise ValueError('match must be None, a matplotlib.artist.Artist '
'subclass, or a callable')
artists = sum([c.findobj(matchfunc) for c in self.get_children()], [])
if include_self and matchfunc(self):
artists.append(self)
return artists
def get_cursor_data(self, event):
"""
Return the cursor data for a given event.
.. note::
This method is intended to be overridden by artist subclasses.
As an end-user of Matplotlib you will most likely not call this
method yourself.
Cursor data can be used by Artists to provide additional context
information for a given event. The default implementation just returns
*None*.
Subclasses can override the method and return arbitrary data. However,
when doing so, they must ensure that `.format_cursor_data` can convert
the data to a string representation.
The only current use case is displaying the z-value of an `.AxesImage`
in the status bar of a plot window, while moving the mouse.
Parameters
----------
event : `~matplotlib.backend_bases.MouseEvent`
See Also
--------
format_cursor_data
"""
return None
def format_cursor_data(self, data):
"""
Return a string representation of *data*.
.. note::
This method is intended to be overridden by artist subclasses.
As an end-user of Matplotlib you will most likely not call this
method yourself.
The default implementation converts ints and floats and arrays of ints
and floats into a comma-separated string enclosed in square brackets,
unless the artist has an associated colorbar, in which case scalar
values are formatted using the colorbar's formatter.
See Also
--------
get_cursor_data
"""
if np.ndim(data) == 0 and isinstance(self, ScalarMappable):
# This block logically belongs to ScalarMappable, but can't be
# implemented in it because most ScalarMappable subclasses inherit
# from Artist first and from ScalarMappable second, so
# Artist.format_cursor_data would always have precedence over
# ScalarMappable.format_cursor_data.
n = self.cmap.N
if np.ma.getmask(data):
return "[]"
normed = self.norm(data)
if np.isfinite(normed):
if isinstance(self.norm, BoundaryNorm):
# not an invertible normalization mapping
cur_idx = np.argmin(np.abs(self.norm.boundaries - data))
neigh_idx = max(0, cur_idx - 1)
# use max diff to prevent delta == 0
delta = np.diff(
self.norm.boundaries[neigh_idx:cur_idx + 2]
).max()
else:
# Midpoints of neighboring color intervals.
neighbors = self.norm.inverse(
(int(normed * n) + np.array([0, 1])) / n)
delta = abs(neighbors - data).max()
g_sig_digits = cbook._g_sig_digits(data, delta)
else:
g_sig_digits = 3 # Consistent with default below.
return f"[{data:-#.{g_sig_digits}g}]"
else:
try:
data[0]
except (TypeError, IndexError):
data = [data]
data_str = ', '.join(f'{item:0.3g}' for item in data
if isinstance(item, Number))
return "[" + data_str + "]"
def get_mouseover(self):
"""
Return whether this artist is queried for custom context information
when the mouse cursor moves over it.
"""
return self._mouseover
def set_mouseover(self, mouseover):
"""
Set whether this artist is queried for custom context information when
the mouse cursor moves over it.
Parameters
----------
mouseover : bool
See Also
--------
get_cursor_data
.ToolCursorPosition
.NavigationToolbar2
"""
self._mouseover = bool(mouseover)
ax = self.axes
if ax:
if self._mouseover:
ax._mouseover_set.add(self)
else:
ax._mouseover_set.discard(self)
mouseover = property(get_mouseover, set_mouseover) # backcompat.
def _get_tightbbox_for_layout_only(obj, *args, **kwargs):
"""
Matplotlib's `.Axes.get_tightbbox` and `.Axis.get_tightbbox` support a
*for_layout_only* kwarg; this helper tries to use the kwarg but skips it
when encountering third-party subclasses that do not support it.
"""
try:
return obj.get_tightbbox(*args, **{**kwargs, "for_layout_only": True})
except TypeError:
return obj.get_tightbbox(*args, **kwargs)
class ArtistInspector:
"""
A helper class to inspect an `~matplotlib.artist.Artist` and return
information about its settable properties and their current values.
"""
def __init__(self, o):
r"""
Initialize the artist inspector with an `Artist` or an iterable of
`Artist`\s. If an iterable is used, we assume it is a homogeneous
sequence (all `Artist`\s are of the same type) and it is your
responsibility to make sure this is so.
"""
if not isinstance(o, Artist):
if np.iterable(o):
o = list(o)
if len(o):
o = o[0]
self.oorig = o
if not isinstance(o, type):
o = type(o)
self.o = o
self.aliasd = self.get_aliases()
def get_aliases(self):
"""
Get a dict mapping property fullnames to sets of aliases for each alias
in the :class:`~matplotlib.artist.ArtistInspector`.
e.g., for lines::
{'markerfacecolor': {'mfc'},
'linewidth' : {'lw'},
}
"""
names = [name for name in dir(self.o)
if name.startswith(('set_', 'get_'))
and callable(getattr(self.o, name))]
aliases = {}
for name in names:
func = getattr(self.o, name)
if not self.is_alias(func):
continue
propname = re.search(f"`({name[:4]}.*)`", # get_.*/set_.*
inspect.getdoc(func)).group(1)
aliases.setdefault(propname[4:], set()).add(name[4:])
return aliases
_get_valid_values_regex = re.compile(
r"\n\s*(?:\.\.\s+)?ACCEPTS:\s*((?:.|\n)*?)(?:$|(?:\n\n))"
)
def get_valid_values(self, attr):
"""
Get the legal arguments for the setter associated with *attr*.
This is done by querying the docstring of the setter for a line that
begins with "ACCEPTS:" or ".. ACCEPTS:", and then by looking for a
numpydoc-style documentation for the setter's first argument.
"""
name = 'set_%s' % attr
if not hasattr(self.o, name):
raise AttributeError(f'{self.o} has no function {name}')
func = getattr(self.o, name)
docstring = inspect.getdoc(func)
if docstring is None:
return 'unknown'
if docstring.startswith('Alias for '):
return None
match = self._get_valid_values_regex.search(docstring)
if match is not None:
return re.sub("\n *", " ", match.group(1))
# Much faster than list(inspect.signature(func).parameters)[1],
# although barely relevant wrt. matplotlib's total import time.
param_name = func.__code__.co_varnames[1]
# We could set the presence * based on whether the parameter is a
# varargs (it can't be a varkwargs) but it's not really worth it.
match = re.search(fr"(?m)^ *\*?{param_name} : (.+)", docstring)
if match:
return match.group(1)
return 'unknown'
def _replace_path(self, source_class):
"""
Changes the full path to the public API path that is used
in sphinx. This is needed for links to work.
"""
replace_dict = {'_base._AxesBase': 'Axes',
'_axes.Axes': 'Axes'}
for key, value in replace_dict.items():
source_class = source_class.replace(key, value)
return source_class
def get_setters(self):
"""
Get the attribute strings with setters for object.
For example, for a line, return ``['markerfacecolor', 'linewidth',
....]``.
"""
setters = []
for name in dir(self.o):
if not name.startswith('set_'):
continue
func = getattr(self.o, name)
if (not callable(func)
or self.number_of_parameters(func) < 2
or self.is_alias(func)):
continue
setters.append(name[4:])
return setters
@staticmethod
@cache
def number_of_parameters(func):
"""Return number of parameters of the callable *func*."""
return len(inspect.signature(func).parameters)
@staticmethod
@cache
def is_alias(method):
"""
Return whether the object *method* is an alias for another method.
"""
ds = inspect.getdoc(method)
if ds is None:
return False
return ds.startswith('Alias for ')
def aliased_name(self, s):
"""
Return 'PROPNAME or alias' if *s* has an alias, else return 'PROPNAME'.
For example, for the line markerfacecolor property, which has an
alias, return 'markerfacecolor or mfc' and for the transform
property, which does not, return 'transform'.
"""
aliases = ''.join(' or %s' % x for x in sorted(self.aliasd.get(s, [])))
return s + aliases
_NOT_LINKABLE = {
# A set of property setter methods that are not available in our
# current docs. This is a workaround used to prevent trying to link
# these setters which would lead to "target reference not found"
# warnings during doc build.
'matplotlib.image._ImageBase.set_alpha',
'matplotlib.image._ImageBase.set_array',
'matplotlib.image._ImageBase.set_data',
'matplotlib.image._ImageBase.set_filternorm',
'matplotlib.image._ImageBase.set_filterrad',
'matplotlib.image._ImageBase.set_interpolation',
'matplotlib.image._ImageBase.set_interpolation_stage',
'matplotlib.image._ImageBase.set_resample',
'matplotlib.text._AnnotationBase.set_annotation_clip',
}
def aliased_name_rest(self, s, target):
"""
Return 'PROPNAME or alias' if *s* has an alias, else return 'PROPNAME',
formatted for reST.
For example, for the line markerfacecolor property, which has an
alias, return 'markerfacecolor or mfc' and for the transform
property, which does not, return 'transform'.
"""
# workaround to prevent "reference target not found"
if target in self._NOT_LINKABLE:
return f'``{s}``'
aliases = ''.join(' or %s' % x for x in sorted(self.aliasd.get(s, [])))
return f':meth:`{s} <{target}>`{aliases}'
def pprint_setters(self, prop=None, leadingspace=2):
"""
If *prop* is *None*, return a list of strings of all settable
properties and their valid values.
If *prop* is not *None*, it is a valid property name and that
property will be returned as a string of property : valid
values.
"""
if leadingspace:
pad = ' ' * leadingspace
else:
pad = ''
if prop is not None:
accepts = self.get_valid_values(prop)
return f'{pad}{prop}: {accepts}'
lines = []
for prop in sorted(self.get_setters()):
accepts = self.get_valid_values(prop)
name = self.aliased_name(prop)
lines.append(f'{pad}{name}: {accepts}')
return lines
def pprint_setters_rest(self, prop=None, leadingspace=4):
"""
If *prop* is *None*, return a list of reST-formatted strings of all
settable properties and their valid values.
If *prop* is not *None*, it is a valid property name and that
property will be returned as a string of "property : valid"
values.
"""
if leadingspace:
pad = ' ' * leadingspace
else:
pad = ''
if prop is not None:
accepts = self.get_valid_values(prop)
return f'{pad}{prop}: {accepts}'
prop_and_qualnames = []
for prop in sorted(self.get_setters()):
# Find the parent method which actually provides the docstring.
for cls in self.o.__mro__:
method = getattr(cls, f"set_{prop}", None)
if method and method.__doc__ is not None:
break
else: # No docstring available.
method = getattr(self.o, f"set_{prop}")
prop_and_qualnames.append(
(prop, f"{method.__module__}.{method.__qualname__}"))
names = [self.aliased_name_rest(prop, target)
.replace('_base._AxesBase', 'Axes')
.replace('_axes.Axes', 'Axes')
for prop, target in prop_and_qualnames]
accepts = [self.get_valid_values(prop)
for prop, _ in prop_and_qualnames]
col0_len = max(len(n) for n in names)
col1_len = max(len(a) for a in accepts)
table_formatstr = pad + ' ' + '=' * col0_len + ' ' + '=' * col1_len
return [
'',
pad + '.. table::',
pad + ' :class: property-table',
'',
table_formatstr,
pad + ' ' + 'Property'.ljust(col0_len)
+ ' ' + 'Description'.ljust(col1_len),
table_formatstr,
*[pad + ' ' + n.ljust(col0_len) + ' ' + a.ljust(col1_len)
for n, a in zip(names, accepts)],
table_formatstr,
'',
]
def properties(self):
"""Return a dictionary mapping property name -> value."""
o = self.oorig
getters = [name for name in dir(o)
if name.startswith('get_') and callable(getattr(o, name))]
getters.sort()
d = {}
for name in getters:
func = getattr(o, name)
if self.is_alias(func):
continue
try:
with warnings.catch_warnings():
warnings.simplefilter('ignore')
val = func()
except Exception:
continue
else:
d[name[4:]] = val
return d
def pprint_getters(self):
"""Return the getters and actual values as list of strings."""
lines = []
for name, val in sorted(self.properties().items()):
if getattr(val, 'shape', ()) != () and len(val) > 6:
s = str(val[:6]) + '...'
else:
s = str(val)
s = s.replace('\n', ' ')
if len(s) > 50:
s = s[:50] + '...'
name = self.aliased_name(name)
lines.append(f' {name} = {s}')
return lines
def getp(obj, property=None):
"""
Return the value of an `.Artist`'s *property*, or print all of them.
Parameters
----------
obj : `~matplotlib.artist.Artist`
The queried artist; e.g., a `.Line2D`, a `.Text`, or an `~.axes.Axes`.
property : str or None, default: None
If *property* is 'somename', this function returns
``obj.get_somename()``.
If it's None (or unset), it *prints* all gettable properties from
*obj*. Many properties have aliases for shorter typing, e.g. 'lw' is
an alias for 'linewidth'. In the output, aliases and full property
names will be listed as:
property or alias = value
e.g.:
linewidth or lw = 2
See Also
--------
setp
"""
if property is None:
insp = ArtistInspector(obj)
ret = insp.pprint_getters()
print('\n'.join(ret))
return
return getattr(obj, 'get_' + property)()
# alias
get = getp
def setp(obj, *args, file=None, **kwargs):
"""
Set one or more properties on an `.Artist`, or list allowed values.
Parameters
----------
obj : `~matplotlib.artist.Artist` or list of `.Artist`
The artist(s) whose properties are being set or queried. When setting
properties, all artists are affected; when querying the allowed values,
only the first instance in the sequence is queried.
For example, two lines can be made thicker and red with a single call:
>>> x = arange(0, 1, 0.01)
>>> lines = plot(x, sin(2*pi*x), x, sin(4*pi*x))
>>> setp(lines, linewidth=2, color='r')
file : file-like, default: `sys.stdout`
Where `setp` writes its output when asked to list allowed values.
>>> with open('output.log') as file:
... setp(line, file=file)
The default, ``None``, means `sys.stdout`.
*args, **kwargs
The properties to set. The following combinations are supported:
- Set the linestyle of a line to be dashed:
>>> line, = plot([1, 2, 3])
>>> setp(line, linestyle='--')
- Set multiple properties at once:
>>> setp(line, linewidth=2, color='r')
- List allowed values for a line's linestyle:
>>> setp(line, 'linestyle')
linestyle: {'-', '--', '-.', ':', '', (offset, on-off-seq), ...}
- List all properties that can be set, and their allowed values:
>>> setp(line)
agg_filter: a filter function, ...
[long output listing omitted]
`setp` also supports MATLAB style string/value pairs. For example, the
following are equivalent:
>>> setp(lines, 'linewidth', 2, 'color', 'r') # MATLAB style
>>> setp(lines, linewidth=2, color='r') # Python style
See Also
--------
getp
"""
if isinstance(obj, Artist):
objs = [obj]
else:
objs = list(cbook.flatten(obj))
if not objs:
return
insp = ArtistInspector(objs[0])
if not kwargs and len(args) < 2:
if args:
print(insp.pprint_setters(prop=args[0]), file=file)
else:
print('\n'.join(insp.pprint_setters()), file=file)
return
if len(args) % 2:
raise ValueError('The set args must be string, value pairs')
funcvals = dict(zip(args[::2], args[1::2]))
ret = [o.update(funcvals) for o in objs] + [o.set(**kwargs) for o in objs]
return list(cbook.flatten(ret))
def kwdoc(artist):
r"""
Inspect an `~matplotlib.artist.Artist` class (using `.ArtistInspector`) and
return information about its settable properties and their current values.
Parameters
----------
artist : `~matplotlib.artist.Artist` or an iterable of `Artist`\s
Returns
-------
str
The settable properties of *artist*, as plain text if
:rc:`docstring.hardcopy` is False and as a rst table (intended for
use in Sphinx) if it is True.
"""
ai = ArtistInspector(artist)
return ('\n'.join(ai.pprint_setters_rest(leadingspace=4))
if mpl.rcParams['docstring.hardcopy'] else
'Properties:\n' + '\n'.join(ai.pprint_setters(leadingspace=4)))
# We defer this to the end of them module, because it needs ArtistInspector
# to be defined.
Artist._update_set_signature_and_docstring()