import numpy as np
import matplotlib
from matplotlib import cbook, docstring, rcParams
from matplotlib.artist import allow_rasterization
import matplotlib.transforms as mtransforms
import matplotlib.patches as mpatches
import matplotlib.path as mpath
[docs]class Spine(mpatches.Patch):
"""
An axis spine -- the line noting the data area boundaries.
Spines are the lines connecting the axis tick marks and noting the
boundaries of the data area. They can be placed at arbitrary
positions. See `~.Spine.set_position` for more information.
The default position is ``('outward', 0)``.
Spines are subclasses of `.Patch`, and inherit much of their behavior.
Spines draw a line, a circle, or an arc depending if
`~.Spine.set_patch_line`, `~.Spine.set_patch_circle`, or
`~.Spine.set_patch_arc` has been called. Line-like is the default.
"""
def __str__(self):
return "Spine"
@docstring.dedent_interpd
def __init__(self, axes, spine_type, path, **kwargs):
"""
Parameters
----------
axes : `~matplotlib.axes.Axes`
The `~.axes.Axes` instance containing the spine.
spine_type : str
The spine type.
path : `~matplotlib.path.Path`
The `.Path` instance used to draw the spine.
Other Parameters
----------------
**kwargs
Valid keyword arguments are:
%(Patch)s
"""
super().__init__(**kwargs)
self.axes = axes
self.set_figure(self.axes.figure)
self.spine_type = spine_type
self.set_facecolor('none')
self.set_edgecolor(rcParams['axes.edgecolor'])
self.set_linewidth(rcParams['axes.linewidth'])
self.set_capstyle('projecting')
self.axis = None
self.set_zorder(2.5)
self.set_transform(self.axes.transData) # default transform
self._bounds = None # default bounds
self._smart_bounds = False # deprecated in 3.2
# Defer initial position determination. (Not much support for
# non-rectangular axes is currently implemented, and this lets
# them pass through the spines machinery without errors.)
self._position = None
cbook._check_isinstance(matplotlib.path.Path, path=path)
self._path = path
# To support drawing both linear and circular spines, this
# class implements Patch behavior three ways. If
# self._patch_type == 'line', behave like a mpatches.PathPatch
# instance. If self._patch_type == 'circle', behave like a
# mpatches.Ellipse instance. If self._patch_type == 'arc', behave like
# a mpatches.Arc instance.
self._patch_type = 'line'
# Behavior copied from mpatches.Ellipse:
# Note: This cannot be calculated until this is added to an Axes
self._patch_transform = mtransforms.IdentityTransform()
[docs] @cbook.deprecated("3.2")
def set_smart_bounds(self, value):
"""Set the spine and associated axis to have smart bounds."""
self._smart_bounds = value
# also set the axis if possible
if self.spine_type in ('left', 'right'):
self.axes.yaxis.set_smart_bounds(value)
elif self.spine_type in ('top', 'bottom'):
self.axes.xaxis.set_smart_bounds(value)
self.stale = True
[docs] @cbook.deprecated("3.2")
def get_smart_bounds(self):
"""Return whether the spine has smart bounds."""
return self._smart_bounds
[docs] def set_patch_arc(self, center, radius, theta1, theta2):
"""Set the spine to be arc-like."""
self._patch_type = 'arc'
self._center = center
self._width = radius * 2
self._height = radius * 2
self._theta1 = theta1
self._theta2 = theta2
self._path = mpath.Path.arc(theta1, theta2)
# arc drawn on axes transform
self.set_transform(self.axes.transAxes)
self.stale = True
[docs] def set_patch_circle(self, center, radius):
"""Set the spine to be circular."""
self._patch_type = 'circle'
self._center = center
self._width = radius * 2
self._height = radius * 2
# circle drawn on axes transform
self.set_transform(self.axes.transAxes)
self.stale = True
[docs] def set_patch_line(self):
"""Set the spine to be linear."""
self._patch_type = 'line'
self.stale = True
# Behavior copied from mpatches.Ellipse:
def _recompute_transform(self):
"""
Notes
-----
This cannot be called until after this has been added to an Axes,
otherwise unit conversion will fail. This makes it very important to
call the accessor method and not directly access the transformation
member variable.
"""
assert self._patch_type in ('arc', 'circle')
center = (self.convert_xunits(self._center[0]),
self.convert_yunits(self._center[1]))
width = self.convert_xunits(self._width)
height = self.convert_yunits(self._height)
self._patch_transform = mtransforms.Affine2D() \
.scale(width * 0.5, height * 0.5) \
.translate(*center)
[docs] def get_window_extent(self, renderer=None):
"""
Return the window extent of the spines in display space, including
padding for ticks (but not their labels)
See Also
--------
matplotlib.axes.Axes.get_tightbbox
matplotlib.axes.Axes.get_window_extent
"""
# make sure the location is updated so that transforms etc are correct:
self._adjust_location()
bb = super().get_window_extent(renderer=renderer)
if self.axis is None:
return bb
bboxes = [bb]
tickstocheck = [self.axis.majorTicks[0]]
if len(self.axis.minorTicks) > 1:
# only pad for minor ticks if there are more than one
# of them. There is always one...
tickstocheck.append(self.axis.minorTicks[1])
for tick in tickstocheck:
bb0 = bb.frozen()
tickl = tick._size
tickdir = tick._tickdir
if tickdir == 'out':
padout = 1
padin = 0
elif tickdir == 'in':
padout = 0
padin = 1
else:
padout = 0.5
padin = 0.5
padout = padout * tickl / 72 * self.figure.dpi
padin = padin * tickl / 72 * self.figure.dpi
if tick.tick1line.get_visible():
if self.spine_type == 'left':
bb0.x0 = bb0.x0 - padout
bb0.x1 = bb0.x1 + padin
elif self.spine_type == 'bottom':
bb0.y0 = bb0.y0 - padout
bb0.y1 = bb0.y1 + padin
if tick.tick2line.get_visible():
if self.spine_type == 'right':
bb0.x1 = bb0.x1 + padout
bb0.x0 = bb0.x0 - padin
elif self.spine_type == 'top':
bb0.y1 = bb0.y1 + padout
bb0.y0 = bb0.y0 - padout
bboxes.append(bb0)
return mtransforms.Bbox.union(bboxes)
[docs] def get_path(self):
return self._path
def _ensure_position_is_set(self):
if self._position is None:
# default position
self._position = ('outward', 0.0) # in points
self.set_position(self._position)
[docs] def register_axis(self, axis):
"""
Register an axis.
An axis should be registered with its corresponding spine from
the Axes instance. This allows the spine to clear any axis
properties when needed.
"""
self.axis = axis
if self.axis is not None:
self.axis.cla()
self.stale = True
[docs] def cla(self):
"""Clear the current spine."""
self._position = None # clear position
if self.axis is not None:
self.axis.cla()
def _adjust_location(self):
"""Automatically set spine bounds to the view interval."""
if self.spine_type == 'circle':
return
if self._bounds is None:
if self.spine_type in ('left', 'right'):
low, high = self.axes.viewLim.intervaly
elif self.spine_type in ('top', 'bottom'):
low, high = self.axes.viewLim.intervalx
else:
raise ValueError('unknown spine spine_type: %s' %
self.spine_type)
if self._smart_bounds: # deprecated in 3.2
# attempt to set bounds in sophisticated way
# handle inverted limits
viewlim_low, viewlim_high = sorted([low, high])
if self.spine_type in ('left', 'right'):
datalim_low, datalim_high = self.axes.dataLim.intervaly
ticks = self.axes.get_yticks()
elif self.spine_type in ('top', 'bottom'):
datalim_low, datalim_high = self.axes.dataLim.intervalx
ticks = self.axes.get_xticks()
# handle inverted limits
ticks = np.sort(ticks)
datalim_low, datalim_high = sorted([datalim_low, datalim_high])
if datalim_low < viewlim_low:
# Data extends past view. Clip line to view.
low = viewlim_low
else:
# Data ends before view ends.
cond = (ticks <= datalim_low) & (ticks >= viewlim_low)
tickvals = ticks[cond]
if len(tickvals):
# A tick is less than or equal to lowest data point.
low = tickvals[-1]
else:
# No tick is available
low = datalim_low
low = max(low, viewlim_low)
if datalim_high > viewlim_high:
# Data extends past view. Clip line to view.
high = viewlim_high
else:
# Data ends before view ends.
cond = (ticks >= datalim_high) & (ticks <= viewlim_high)
tickvals = ticks[cond]
if len(tickvals):
# A tick is greater than or equal to highest data
# point.
high = tickvals[0]
else:
# No tick is available
high = datalim_high
high = min(high, viewlim_high)
else:
low, high = self._bounds
if self._patch_type == 'arc':
if self.spine_type in ('bottom', 'top'):
try:
direction = self.axes.get_theta_direction()
except AttributeError:
direction = 1
try:
offset = self.axes.get_theta_offset()
except AttributeError:
offset = 0
low = low * direction + offset
high = high * direction + offset
if low > high:
low, high = high, low
self._path = mpath.Path.arc(np.rad2deg(low), np.rad2deg(high))
if self.spine_type == 'bottom':
rmin, rmax = self.axes.viewLim.intervaly
try:
rorigin = self.axes.get_rorigin()
except AttributeError:
rorigin = rmin
scaled_diameter = (rmin - rorigin) / (rmax - rorigin)
self._height = scaled_diameter
self._width = scaled_diameter
else:
raise ValueError('unable to set bounds for spine "%s"' %
self.spine_type)
else:
v1 = self._path.vertices
assert v1.shape == (2, 2), 'unexpected vertices shape'
if self.spine_type in ['left', 'right']:
v1[0, 1] = low
v1[1, 1] = high
elif self.spine_type in ['bottom', 'top']:
v1[0, 0] = low
v1[1, 0] = high
else:
raise ValueError('unable to set bounds for spine "%s"' %
self.spine_type)
[docs] @allow_rasterization
def draw(self, renderer):
self._adjust_location()
ret = super().draw(renderer)
self.stale = False
return ret
[docs] def set_position(self, position):
"""
Set the position of the spine.
Spine position is specified by a 2 tuple of (position type,
amount). The position types are:
* 'outward': place the spine out from the data area by the specified
number of points. (Negative values place the spine inwards.)
* 'axes': place the spine at the specified Axes coordinate (0 to 1).
* 'data': place the spine at the specified data coordinate.
Additionally, shorthand notations define a special positions:
* 'center' -> ('axes', 0.5)
* 'zero' -> ('data', 0.0)
"""
if position in ('center', 'zero'): # special positions
pass
else:
if len(position) != 2:
raise ValueError("position should be 'center' or 2-tuple")
if position[0] not in ['outward', 'axes', 'data']:
raise ValueError("position[0] should be one of 'outward', "
"'axes', or 'data' ")
self._position = position
self.set_transform(self.get_spine_transform())
if self.axis is not None:
self.axis.reset_ticks()
self.stale = True
[docs] def get_position(self):
"""Return the spine position."""
self._ensure_position_is_set()
return self._position
[docs] def set_bounds(self, low=None, high=None):
"""
Set the spine bounds.
Parameters
----------
low : float or None, optional
The lower spine bound. Passing *None* leaves the limit unchanged.
The bounds may also be passed as the tuple (*low*, *high*) as the
first positional argument.
.. ACCEPTS: (low: float, high: float)
high : float or None, optional
The higher spine bound. Passing *None* leaves the limit unchanged.
"""
if self.spine_type == 'circle':
raise ValueError(
'set_bounds() method incompatible with circular spines')
if high is None and np.iterable(low):
low, high = low
old_low, old_high = self.get_bounds() or (None, None)
if low is None:
low = old_low
if high is None:
high = old_high
self._bounds = (low, high)
self.stale = True
[docs] def get_bounds(self):
"""Get the bounds of the spine."""
return self._bounds
[docs] @classmethod
def linear_spine(cls, axes, spine_type, **kwargs):
"""Create and return a linear `Spine`."""
# all values of 0.999 get replaced upon call to set_bounds()
if spine_type == 'left':
path = mpath.Path([(0.0, 0.999), (0.0, 0.999)])
elif spine_type == 'right':
path = mpath.Path([(1.0, 0.999), (1.0, 0.999)])
elif spine_type == 'bottom':
path = mpath.Path([(0.999, 0.0), (0.999, 0.0)])
elif spine_type == 'top':
path = mpath.Path([(0.999, 1.0), (0.999, 1.0)])
else:
raise ValueError('unable to make path for spine "%s"' % spine_type)
result = cls(axes, spine_type, path, **kwargs)
result.set_visible(rcParams['axes.spines.{0}'.format(spine_type)])
return result
[docs] @classmethod
def arc_spine(cls, axes, spine_type, center, radius, theta1, theta2,
**kwargs):
"""Create and return an arc `Spine`."""
path = mpath.Path.arc(theta1, theta2)
result = cls(axes, spine_type, path, **kwargs)
result.set_patch_arc(center, radius, theta1, theta2)
return result
[docs] @classmethod
def circular_spine(cls, axes, center, radius, **kwargs):
"""Create and return a circular `Spine`."""
path = mpath.Path.unit_circle()
spine_type = 'circle'
result = cls(axes, spine_type, path, **kwargs)
result.set_patch_circle(center, radius)
return result
[docs] def set_color(self, c):
"""
Set the edgecolor.
Parameters
----------
c : color
Notes
-----
This method does not modify the facecolor (which defaults to "none"),
unlike the `.Patch.set_color` method defined in the parent class. Use
`.Patch.set_facecolor` to set the facecolor.
"""
self.set_edgecolor(c)
self.stale = True
