Source code for mpl_toolkits.axisartist.axislines

"""
Axislines includes modified implementation of the Axes class. The
biggest difference is that the artists responsible for drawing the axis spine,
ticks, ticklabels and axis labels are separated out from Matplotlib's Axis
class. Originally, this change was motivated to support curvilinear
grid. Here are a few reasons that I came up with a new axes class:

* "top" and "bottom" x-axis (or "left" and "right" y-axis) can have
  different ticks (tick locations and labels). This is not possible
  with the current Matplotlib, although some twin axes trick can help.

* Curvilinear grid.

* angled ticks.

In the new axes class, xaxis and yaxis is set to not visible by
default, and new set of artist (AxisArtist) are defined to draw axis
line, ticks, ticklabels and axis label. Axes.axis attribute serves as
a dictionary of these artists, i.e., ax.axis["left"] is a AxisArtist
instance responsible to draw left y-axis. The default Axes.axis contains
"bottom", "left", "top" and "right".

AxisArtist can be considered as a container artist and
has following children artists which will draw ticks, labels, etc.

* line
* major_ticks, major_ticklabels
* minor_ticks, minor_ticklabels
* offsetText
* label

Note that these are separate artists from `matplotlib.axis.Axis`, thus most
tick-related functions in Matplotlib won't work. For example, color and
markerwidth of the ``ax.axis["bottom"].major_ticks`` will follow those of
Axes.xaxis unless explicitly specified.

In addition to AxisArtist, the Axes will have *gridlines* attribute,
which obviously draws grid lines. The gridlines needs to be separated
from the axis as some gridlines can never pass any axis.
"""

import numpy as np

from matplotlib import _api, rcParams
import matplotlib.axes as maxes
from matplotlib.path import Path
from mpl_toolkits.axes_grid1 import mpl_axes
from .axisline_style import AxislineStyle
from .axis_artist import AxisArtist, GridlinesCollection


[docs]class AxisArtistHelper: """ AxisArtistHelper should define following method with given APIs. Note that the first axes argument will be axes attribute of the caller artist.:: # LINE (spinal line?) def get_line(self, axes): # path : Path return path def get_line_transform(self, axes): # ... # trans : transform return trans # LABEL def get_label_pos(self, axes): # x, y : position return (x, y), trans def get_label_offset_transform(self, axes, pad_points, fontprops, renderer, bboxes, ): # va : vertical alignment # ha : horizontal alignment # a : angle return trans, va, ha, a # TICK def get_tick_transform(self, axes): return trans def get_tick_iterators(self, axes): # iter : iterable object that yields (c, angle, l) where # c, angle, l is position, tick angle, and label return iter_major, iter_minor """ class _Base: """Base class for axis helper.""" def __init__(self): self.delta1, self.delta2 = 0.00001, 0.00001 def update_lim(self, axes): pass
[docs] class Fixed(_Base): """Helper class for a fixed (in the axes coordinate) axis.""" _default_passthru_pt = dict(left=(0, 0), right=(1, 0), bottom=(0, 0), top=(0, 1)) def __init__(self, loc, nth_coord=None): """ nth_coord = along which coordinate value varies in 2D, nth_coord = 0 -> x axis, nth_coord = 1 -> y axis """ _api.check_in_list(["left", "right", "bottom", "top"], loc=loc) self._loc = loc if nth_coord is None: if loc in ["left", "right"]: nth_coord = 1 elif loc in ["bottom", "top"]: nth_coord = 0 self.nth_coord = nth_coord super().__init__() self.passthru_pt = self._default_passthru_pt[loc] _verts = np.array([[0., 0.], [1., 1.]]) fixed_coord = 1 - nth_coord _verts[:, fixed_coord] = self.passthru_pt[fixed_coord] # axis line in transAxes self._path = Path(_verts)
[docs] def get_nth_coord(self): return self.nth_coord
# LINE
[docs] def get_line(self, axes): return self._path
[docs] def get_line_transform(self, axes): return axes.transAxes
# LABEL
[docs] def get_axislabel_transform(self, axes): return axes.transAxes
[docs] def get_axislabel_pos_angle(self, axes): """ Return the label reference position in transAxes. get_label_transform() returns a transform of (transAxes+offset) """ return dict(left=((0., 0.5), 90), # (position, angle_tangent) right=((1., 0.5), 90), bottom=((0.5, 0.), 0), top=((0.5, 1.), 0))[self._loc]
# TICK
[docs] def get_tick_transform(self, axes): return [axes.get_xaxis_transform(), axes.get_yaxis_transform()][self.nth_coord]
[docs] class Floating(_Base): def __init__(self, nth_coord, value): self.nth_coord = nth_coord self._value = value super().__init__()
[docs] def get_nth_coord(self): return self.nth_coord
[docs] def get_line(self, axes): raise RuntimeError( "get_line method should be defined by the derived class")
[docs]class AxisArtistHelperRectlinear:
[docs] class Fixed(AxisArtistHelper.Fixed): def __init__(self, axes, loc, nth_coord=None): """ nth_coord = along which coordinate value varies in 2D, nth_coord = 0 -> x axis, nth_coord = 1 -> y axis """ super().__init__(loc, nth_coord) self.axis = [axes.xaxis, axes.yaxis][self.nth_coord] # TICK
[docs] def get_tick_iterators(self, axes): """tick_loc, tick_angle, tick_label""" loc = self._loc if loc in ["bottom", "top"]: angle_normal, angle_tangent = 90, 0 else: angle_normal, angle_tangent = 0, 90 major = self.axis.major majorLocs = major.locator() majorLabels = major.formatter.format_ticks(majorLocs) minor = self.axis.minor minorLocs = minor.locator() minorLabels = minor.formatter.format_ticks(minorLocs) tick_to_axes = self.get_tick_transform(axes) - axes.transAxes def _f(locs, labels): for x, l in zip(locs, labels): c = list(self.passthru_pt) # copy c[self.nth_coord] = x # check if the tick point is inside axes c2 = tick_to_axes.transform(c) if (0 - self.delta1 <= c2[self.nth_coord] <= 1 + self.delta2): yield c, angle_normal, angle_tangent, l return _f(majorLocs, majorLabels), _f(minorLocs, minorLabels)
[docs] class Floating(AxisArtistHelper.Floating): def __init__(self, axes, nth_coord, passingthrough_point, axis_direction="bottom"): super().__init__(nth_coord, passingthrough_point) self._axis_direction = axis_direction self.axis = [axes.xaxis, axes.yaxis][self.nth_coord]
[docs] def get_line(self, axes): _verts = np.array([[0., 0.], [1., 1.]]) fixed_coord = 1 - self.nth_coord data_to_axes = axes.transData - axes.transAxes p = data_to_axes.transform([self._value, self._value]) _verts[:, fixed_coord] = p[fixed_coord] return Path(_verts)
[docs] def get_line_transform(self, axes): return axes.transAxes
[docs] def get_axislabel_transform(self, axes): return axes.transAxes
[docs] def get_axislabel_pos_angle(self, axes): """ Return the label reference position in transAxes. get_label_transform() returns a transform of (transAxes+offset) """ angle = [0, 90][self.nth_coord] _verts = [0.5, 0.5] fixed_coord = 1 - self.nth_coord data_to_axes = axes.transData - axes.transAxes p = data_to_axes.transform([self._value, self._value]) _verts[fixed_coord] = p[fixed_coord] if 0 <= _verts[fixed_coord] <= 1: return _verts, angle else: return None, None
[docs] def get_tick_transform(self, axes): return axes.transData
[docs] def get_tick_iterators(self, axes): """tick_loc, tick_angle, tick_label""" if self.nth_coord == 0: angle_normal, angle_tangent = 90, 0 else: angle_normal, angle_tangent = 0, 90 major = self.axis.major majorLocs = major.locator() majorLabels = major.formatter.format_ticks(majorLocs) minor = self.axis.minor minorLocs = minor.locator() minorLabels = minor.formatter.format_ticks(minorLocs) data_to_axes = axes.transData - axes.transAxes def _f(locs, labels): for x, l in zip(locs, labels): c = [self._value, self._value] c[self.nth_coord] = x c1, c2 = data_to_axes.transform(c) if (0 <= c1 <= 1 and 0 <= c2 <= 1 and 0 - self.delta1 <= [c1, c2][self.nth_coord] <= 1 + self.delta2): yield c, angle_normal, angle_tangent, l return _f(majorLocs, majorLabels), _f(minorLocs, minorLabels)
[docs]class GridHelperBase: def __init__(self): self._force_update = True # Remove together with invalidate()/valid(). self._old_limits = None super().__init__()
[docs] def update_lim(self, axes): x1, x2 = axes.get_xlim() y1, y2 = axes.get_ylim() if self._force_update or self._old_limits != (x1, x2, y1, y2): self._update_grid(x1, y1, x2, y2) self._force_update = False self._old_limits = (x1, x2, y1, y2)
def _update_grid(self, x1, y1, x2, y2): """Cache relevant computations when the axes limits have changed."""
[docs] @_api.deprecated("3.4") def invalidate(self): self._force_update = True
[docs] @_api.deprecated("3.4") def valid(self): return not self._force_update
[docs] def get_gridlines(self, which, axis): """ Return list of grid lines as a list of paths (list of points). *which* : "major" or "minor" *axis* : "both", "x" or "y" """ return []
[docs] def new_gridlines(self, ax): """ Create and return a new GridlineCollection instance. *which* : "major" or "minor" *axis* : "both", "x" or "y" """ gridlines = GridlinesCollection(None, transform=ax.transData, colors=rcParams['grid.color'], linestyles=rcParams['grid.linestyle'], linewidths=rcParams['grid.linewidth']) ax._set_artist_props(gridlines) gridlines.set_grid_helper(self) ax.axes._set_artist_props(gridlines) # gridlines.set_clip_path(self.axes.patch) # set_clip_path need to be deferred after Axes.cla is completed. # It is done inside the cla. return gridlines
[docs]class GridHelperRectlinear(GridHelperBase): def __init__(self, axes): super().__init__() self.axes = axes
[docs] def new_fixed_axis(self, loc, nth_coord=None, axis_direction=None, offset=None, axes=None, ): if axes is None: _api.warn_external( "'new_fixed_axis' explicitly requires the axes keyword.") axes = self.axes _helper = AxisArtistHelperRectlinear.Fixed(axes, loc, nth_coord) if axis_direction is None: axis_direction = loc axisline = AxisArtist(axes, _helper, offset=offset, axis_direction=axis_direction, ) return axisline
[docs] def new_floating_axis(self, nth_coord, value, axis_direction="bottom", axes=None, ): if axes is None: _api.warn_external( "'new_floating_axis' explicitly requires the axes keyword.") axes = self.axes _helper = AxisArtistHelperRectlinear.Floating( axes, nth_coord, value, axis_direction) axisline = AxisArtist(axes, _helper, axis_direction=axis_direction) axisline.line.set_clip_on(True) axisline.line.set_clip_box(axisline.axes.bbox) return axisline
[docs] def get_gridlines(self, which="major", axis="both"): """ Return list of gridline coordinates in data coordinates. *which* : "major" or "minor" *axis* : "both", "x" or "y" """ gridlines = [] if axis in ["both", "x"]: locs = [] y1, y2 = self.axes.get_ylim() if which in ["both", "major"]: locs.extend(self.axes.xaxis.major.locator()) if which in ["both", "minor"]: locs.extend(self.axes.xaxis.minor.locator()) for x in locs: gridlines.append([[x, x], [y1, y2]]) if axis in ["both", "y"]: x1, x2 = self.axes.get_xlim() locs = [] if self.axes.yaxis._major_tick_kw["gridOn"]: locs.extend(self.axes.yaxis.major.locator()) if self.axes.yaxis._minor_tick_kw["gridOn"]: locs.extend(self.axes.yaxis.minor.locator()) for y in locs: gridlines.append([[x1, x2], [y, y]]) return gridlines
[docs]class Axes(maxes.Axes):
[docs] def __call__(self, *args, **kwargs): return maxes.Axes.axis(self.axes, *args, **kwargs)
def __init__(self, *args, grid_helper=None, **kwargs): self._axisline_on = True self._grid_helper = (grid_helper if grid_helper else GridHelperRectlinear(self)) super().__init__(*args, **kwargs) self.toggle_axisline(True)
[docs] def toggle_axisline(self, b=None): if b is None: b = not self._axisline_on if b: self._axisline_on = True self.spines[:].set_visible(False) self.xaxis.set_visible(False) self.yaxis.set_visible(False) else: self._axisline_on = False self.spines[:].set_visible(True) self.xaxis.set_visible(True) self.yaxis.set_visible(True)
def _init_axis_artists(self, axes=None): if axes is None: axes = self self._axislines = mpl_axes.Axes.AxisDict(self) new_fixed_axis = self.get_grid_helper().new_fixed_axis for loc in ["bottom", "top", "left", "right"]: self._axislines[loc] = new_fixed_axis(loc=loc, axes=axes, axis_direction=loc) for axisline in [self._axislines["top"], self._axislines["right"]]: axisline.label.set_visible(False) axisline.major_ticklabels.set_visible(False) axisline.minor_ticklabels.set_visible(False) @property def axis(self): return self._axislines
[docs] def new_gridlines(self, grid_helper=None): """ Create and return a new GridlineCollection instance. *which* : "major" or "minor" *axis* : "both", "x" or "y" """ if grid_helper is None: grid_helper = self.get_grid_helper() gridlines = grid_helper.new_gridlines(self) return gridlines
def _init_gridlines(self, grid_helper=None): # It is done inside the cla. self.gridlines = self.new_gridlines(grid_helper)
[docs] def cla(self): # gridlines need to b created before cla() since cla calls grid() self._init_gridlines() super().cla() # the clip_path should be set after Axes.cla() since that's # when a patch is created. self.gridlines.set_clip_path(self.axes.patch) self._init_axis_artists()
[docs] def get_grid_helper(self): return self._grid_helper
[docs] @_api.rename_parameter("3.5", "b", "visible") def grid(self, visible=None, which='major', axis="both", **kwargs): """ Toggle the gridlines, and optionally set the properties of the lines. """ # There are some discrepancies in the behavior of grid() between # axes_grid and Matplotlib, because axes_grid explicitly sets the # visibility of the gridlines. super().grid(visible, which=which, axis=axis, **kwargs) if not self._axisline_on: return if visible is None: visible = (self.axes.xaxis._minor_tick_kw["gridOn"] or self.axes.xaxis._major_tick_kw["gridOn"] or self.axes.yaxis._minor_tick_kw["gridOn"] or self.axes.yaxis._major_tick_kw["gridOn"]) self.gridlines.set(which=which, axis=axis, visible=visible) self.gridlines.set(**kwargs)
[docs] def get_children(self): if self._axisline_on: children = [*self._axislines.values(), self.gridlines] else: children = [] children.extend(super().get_children()) return children
[docs] @_api.deprecated("3.4") def invalidate_grid_helper(self): self._grid_helper.invalidate()
[docs] def new_fixed_axis(self, loc, offset=None): gh = self.get_grid_helper() axis = gh.new_fixed_axis(loc, nth_coord=None, axis_direction=None, offset=offset, axes=self, ) return axis
[docs] def new_floating_axis(self, nth_coord, value, axis_direction="bottom"): gh = self.get_grid_helper() axis = gh.new_floating_axis(nth_coord, value, axis_direction=axis_direction, axes=self) return axis
Subplot = maxes.subplot_class_factory(Axes)
[docs]class AxesZero(Axes): def _init_axis_artists(self): super()._init_axis_artists() new_floating_axis = self._grid_helper.new_floating_axis xaxis_zero = new_floating_axis(nth_coord=0, value=0., axis_direction="bottom", axes=self) xaxis_zero.line.set_clip_path(self.patch) xaxis_zero.set_visible(False) self._axislines["xzero"] = xaxis_zero yaxis_zero = new_floating_axis(nth_coord=1, value=0., axis_direction="left", axes=self) yaxis_zero.line.set_clip_path(self.patch) yaxis_zero.set_visible(False) self._axislines["yzero"] = yaxis_zero
SubplotZero = maxes.subplot_class_factory(AxesZero)