You are reading an old version of the documentation (v2.2.3). For the latest version see https://matplotlib.org/stable/_modules/matplotlib/projections/polar.html
Version 2.2.3
matplotlib
Fork me on GitHub

Source code for matplotlib.projections.polar

from __future__ import (absolute_import, division, print_function,
                        unicode_literals)

import six

from collections import OrderedDict

import numpy as np

from matplotlib.axes import Axes
import matplotlib.axis as maxis
from matplotlib import cbook
from matplotlib import docstring
import matplotlib.markers as mmarkers
import matplotlib.patches as mpatches
import matplotlib.path as mpath
from matplotlib import rcParams
import matplotlib.ticker as mticker
import matplotlib.transforms as mtransforms
import matplotlib.spines as mspines


[docs]class PolarTransform(mtransforms.Transform): """ The base polar transform. This handles projection *theta* and *r* into Cartesian coordinate space *x* and *y*, but does not perform the ultimate affine transformation into the correct position. """ input_dims = 2 output_dims = 2 is_separable = False def __init__(self, axis=None, use_rmin=True, _apply_theta_transforms=True): mtransforms.Transform.__init__(self) self._axis = axis self._use_rmin = use_rmin self._apply_theta_transforms = _apply_theta_transforms def __str__(self): return ("{}(\n" "{},\n" " use_rmin={},\n" " _apply_theta_transforms={})" .format(type(self).__name__, mtransforms._indent_str(self._axis), self._use_rmin, self._apply_theta_transforms))
[docs] def transform_non_affine(self, tr): xy = np.empty(tr.shape, float) t = tr[:, 0:1] r = tr[:, 1:2] x = xy[:, 0:1] y = xy[:, 1:2] # PolarAxes does not use the theta transforms here, but apply them for # backwards-compatibility if not being used by it. if self._apply_theta_transforms and self._axis is not None: t *= self._axis.get_theta_direction() t += self._axis.get_theta_offset() if self._use_rmin and self._axis is not None: r = r - self._axis.get_rorigin() mask = r < 0 x[:] = np.where(mask, np.nan, r * np.cos(t)) y[:] = np.where(mask, np.nan, r * np.sin(t)) return xy
transform_non_affine.__doc__ = \ mtransforms.Transform.transform_non_affine.__doc__
[docs] def transform_path_non_affine(self, path): vertices = path.vertices if len(vertices) == 2 and vertices[0, 0] == vertices[1, 0]: return mpath.Path(self.transform(vertices), path.codes) ipath = path.interpolated(path._interpolation_steps) return mpath.Path(self.transform(ipath.vertices), ipath.codes)
transform_path_non_affine.__doc__ = \ mtransforms.Transform.transform_path_non_affine.__doc__
[docs] def inverted(self): return PolarAxes.InvertedPolarTransform(self._axis, self._use_rmin, self._apply_theta_transforms)
inverted.__doc__ = mtransforms.Transform.inverted.__doc__
[docs]class PolarAffine(mtransforms.Affine2DBase): """ The affine part of the polar projection. Scales the output so that maximum radius rests on the edge of the axes circle. """ def __init__(self, scale_transform, limits): """ *limits* is the view limit of the data. The only part of its bounds that is used is the y limits (for the radius limits). The theta range is handled by the non-affine transform. """ mtransforms.Affine2DBase.__init__(self) self._scale_transform = scale_transform self._limits = limits self.set_children(scale_transform, limits) self._mtx = None def __str__(self): return ("{}(\n" "{},\n" "{})" .format(type(self).__name__, mtransforms._indent_str(self._scale_transform), mtransforms._indent_str(self._limits)))
[docs] def get_matrix(self): if self._invalid: limits_scaled = self._limits.transformed(self._scale_transform) yscale = limits_scaled.ymax - limits_scaled.ymin affine = mtransforms.Affine2D() \ .scale(0.5 / yscale) \ .translate(0.5, 0.5) self._mtx = affine.get_matrix() self._inverted = None self._invalid = 0 return self._mtx
get_matrix.__doc__ = mtransforms.Affine2DBase.get_matrix.__doc__
[docs]class InvertedPolarTransform(mtransforms.Transform): """ The inverse of the polar transform, mapping Cartesian coordinate space *x* and *y* back to *theta* and *r*. """ input_dims = 2 output_dims = 2 is_separable = False def __init__(self, axis=None, use_rmin=True, _apply_theta_transforms=True): mtransforms.Transform.__init__(self) self._axis = axis self._use_rmin = use_rmin self._apply_theta_transforms = _apply_theta_transforms def __str__(self): return ("{}(\n" "{},\n" " use_rmin={},\n" " _apply_theta_transforms={})" .format(type(self).__name__, mtransforms._indent_str(self._axis), self._use_rmin, self._apply_theta_transforms))
[docs] def transform_non_affine(self, xy): x = xy[:, 0:1] y = xy[:, 1:] r = np.sqrt(x*x + y*y) with np.errstate(invalid='ignore'): # At x=y=r=0 this will raise an # invalid value warning when doing 0/0 # Divide by zero warnings are only raised when # the numerator is different from 0. That # should not happen here. theta = np.arccos(x / r) theta = np.where(y < 0, 2 * np.pi - theta, theta) # PolarAxes does not use the theta transforms here, but apply them for # backwards-compatibility if not being used by it. if self._apply_theta_transforms and self._axis is not None: theta -= self._axis.get_theta_offset() theta *= self._axis.get_theta_direction() theta %= 2 * np.pi if self._use_rmin and self._axis is not None: r += self._axis.get_rorigin() return np.concatenate((theta, r), 1)
transform_non_affine.__doc__ = \ mtransforms.Transform.transform_non_affine.__doc__
[docs] def inverted(self): return PolarAxes.PolarTransform(self._axis, self._use_rmin, self._apply_theta_transforms)
inverted.__doc__ = mtransforms.Transform.inverted.__doc__
[docs]class ThetaFormatter(mticker.Formatter): """ Used to format the *theta* tick labels. Converts the native unit of radians into degrees and adds a degree symbol. """ def __call__(self, x, pos=None): vmin, vmax = self.axis.get_view_interval() d = np.rad2deg(abs(vmax - vmin)) digits = max(-int(np.log10(d) - 1.5), 0) if rcParams['text.usetex'] and not rcParams['text.latex.unicode']: format_str = r"${value:0.{digits:d}f}^\circ$" return format_str.format(value=np.rad2deg(x), digits=digits) else: # we use unicode, rather than mathtext with \circ, so # that it will work correctly with any arbitrary font # (assuming it has a degree sign), whereas $5\circ$ # will only work correctly with one of the supported # math fonts (Computer Modern and STIX) format_str = "{value:0.{digits:d}f}\N{DEGREE SIGN}" return format_str.format(value=np.rad2deg(x), digits=digits)
class _AxisWrapper(object): def __init__(self, axis): self._axis = axis def get_view_interval(self): return np.rad2deg(self._axis.get_view_interval()) def set_view_interval(self, vmin, vmax): self._axis.set_view_interval(*np.deg2rad((vmin, vmax))) def get_minpos(self): return np.rad2deg(self._axis.get_minpos()) def get_data_interval(self): return np.rad2deg(self._axis.get_data_interval()) def set_data_interval(self, vmin, vmax): self._axis.set_data_interval(*np.deg2rad((vmin, vmax))) def get_tick_space(self): return self._axis.get_tick_space()
[docs]class ThetaLocator(mticker.Locator): """ Used to locate theta ticks. This will work the same as the base locator except in the case that the view spans the entire circle. In such cases, the previously used default locations of every 45 degrees are returned. """ def __init__(self, base): self.base = base self.axis = self.base.axis = _AxisWrapper(self.base.axis)
[docs] def set_axis(self, axis): self.axis = _AxisWrapper(axis) self.base.set_axis(self.axis)
def __call__(self): lim = self.axis.get_view_interval() if _is_full_circle_deg(lim[0], lim[1]): return np.arange(8) * 2 * np.pi / 8 else: return np.deg2rad(self.base())
[docs] def autoscale(self): return self.base.autoscale()
[docs] def pan(self, numsteps): return self.base.pan(numsteps)
[docs] def refresh(self): return self.base.refresh()
[docs] def view_limits(self, vmin, vmax): vmin, vmax = np.rad2deg((vmin, vmax)) return np.deg2rad(self.base.view_limits(vmin, vmax))
[docs] def zoom(self, direction): return self.base.zoom(direction)
[docs]class ThetaTick(maxis.XTick): """ A theta-axis tick. This subclass of `XTick` provides angular ticks with some small modification to their re-positioning such that ticks are rotated based on tick location. This results in ticks that are correctly perpendicular to the arc spine. When 'auto' rotation is enabled, labels are also rotated to be parallel to the spine. The label padding is also applied here since it's not possible to use a generic axes transform to produce tick-specific padding. """ def __init__(self, axes, *args, **kwargs): self._text1_translate = mtransforms.ScaledTranslation( 0, 0, axes.figure.dpi_scale_trans) self._text2_translate = mtransforms.ScaledTranslation( 0, 0, axes.figure.dpi_scale_trans) super(ThetaTick, self).__init__(axes, *args, **kwargs) def _get_text1(self): t = super(ThetaTick, self)._get_text1() t.set_rotation_mode('anchor') t.set_transform(t.get_transform() + self._text1_translate) return t def _get_text2(self): t = super(ThetaTick, self)._get_text2() t.set_rotation_mode('anchor') t.set_transform(t.get_transform() + self._text2_translate) return t def _apply_params(self, **kw): super(ThetaTick, self)._apply_params(**kw) # Ensure transform is correct; sometimes this gets reset. trans = self.label1.get_transform() if not trans.contains_branch(self._text1_translate): self.label1.set_transform(trans + self._text1_translate) trans = self.label2.get_transform() if not trans.contains_branch(self._text2_translate): self.label2.set_transform(trans + self._text2_translate) def _update_padding(self, pad, angle): padx = pad * np.cos(angle) / 72 pady = pad * np.sin(angle) / 72 self._text1_translate._t = (padx, pady) self._text1_translate.invalidate() self._text2_translate._t = (-padx, -pady) self._text2_translate.invalidate()
[docs] def update_position(self, loc): super(ThetaTick, self).update_position(loc) axes = self.axes angle = loc * axes.get_theta_direction() + axes.get_theta_offset() text_angle = np.rad2deg(angle) % 360 - 90 angle -= np.pi / 2 if self.tick1On: marker = self.tick1line.get_marker() if marker in (mmarkers.TICKUP, '|'): trans = mtransforms.Affine2D().scale(1.0, 1.0).rotate(angle) elif marker == mmarkers.TICKDOWN: trans = mtransforms.Affine2D().scale(1.0, -1.0).rotate(angle) else: # Don't modify custom tick line markers. trans = self.tick1line._marker._transform self.tick1line._marker._transform = trans if self.tick2On: marker = self.tick2line.get_marker() if marker in (mmarkers.TICKUP, '|'): trans = mtransforms.Affine2D().scale(1.0, 1.0).rotate(angle) elif marker == mmarkers.TICKDOWN: trans = mtransforms.Affine2D().scale(1.0, -1.0).rotate(angle) else: # Don't modify custom tick line markers. trans = self.tick2line._marker._transform self.tick2line._marker._transform = trans mode, user_angle = self._labelrotation if mode == 'default': text_angle = user_angle else: if text_angle > 90: text_angle -= 180 elif text_angle < -90: text_angle += 180 text_angle += user_angle if self.label1On: self.label1.set_rotation(text_angle) if self.label2On: self.label2.set_rotation(text_angle) # This extra padding helps preserve the look from previous releases but # is also needed because labels are anchored to their center. pad = self._pad + 7 self._update_padding(pad, self._loc * axes.get_theta_direction() + axes.get_theta_offset())
[docs]class ThetaAxis(maxis.XAxis): """ A theta Axis. This overrides certain properties of an `XAxis` to provide special-casing for an angular axis. """ __name__ = 'thetaaxis' axis_name = 'theta' def _get_tick(self, major): if major: tick_kw = self._major_tick_kw else: tick_kw = self._minor_tick_kw return ThetaTick(self.axes, 0, '', major=major, **tick_kw) def _wrap_locator_formatter(self): self.set_major_locator(ThetaLocator(self.get_major_locator())) self.set_major_formatter(ThetaFormatter()) self.isDefault_majloc = True self.isDefault_majfmt = True
[docs] def cla(self): super(ThetaAxis, self).cla() self.set_ticks_position('none') self._wrap_locator_formatter()
def _set_scale(self, value, **kwargs): super(ThetaAxis, self)._set_scale(value, **kwargs) self._wrap_locator_formatter() def _copy_tick_props(self, src, dest): 'Copy the props from src tick to dest tick' if src is None or dest is None: return super(ThetaAxis, self)._copy_tick_props(src, dest) # Ensure that tick transforms are independent so that padding works. trans = dest._get_text1_transform()[0] dest.label1.set_transform(trans + dest._text1_translate) trans = dest._get_text2_transform()[0] dest.label2.set_transform(trans + dest._text2_translate)
[docs]class RadialLocator(mticker.Locator): """ Used to locate radius ticks. Ensures that all ticks are strictly positive. For all other tasks, it delegates to the base :class:`~matplotlib.ticker.Locator` (which may be different depending on the scale of the *r*-axis. """ def __init__(self, base, axes=None): self.base = base self._axes = axes def __call__(self): show_all = True # Ensure previous behaviour with full circle non-annular views. if self._axes: if _is_full_circle_rad(*self._axes.viewLim.intervalx): rorigin = self._axes.get_rorigin() if self._axes.get_rmin() <= rorigin: show_all = False if show_all: return self.base() else: return [tick for tick in self.base() if tick > rorigin]
[docs] def autoscale(self): return self.base.autoscale()
[docs] def pan(self, numsteps): return self.base.pan(numsteps)
[docs] def zoom(self, direction): return self.base.zoom(direction)
[docs] def refresh(self): return self.base.refresh()
[docs] def view_limits(self, vmin, vmax): vmin, vmax = self.base.view_limits(vmin, vmax) return mtransforms.nonsingular(min(0, vmin), vmax)
class _ThetaShift(mtransforms.ScaledTranslation): """ Apply a padding shift based on axes theta limits. This is used to create padding for radial ticks. Parameters ---------- axes : matplotlib.axes.Axes The owning axes; used to determine limits. pad : float The padding to apply, in points. start : str, {'min', 'max', 'rlabel'} Whether to shift away from the start (``'min'``) or the end (``'max'``) of the axes, or using the rlabel position (``'rlabel'``). """ def __init__(self, axes, pad, mode): mtransforms.ScaledTranslation.__init__(self, pad, pad, axes.figure.dpi_scale_trans) self.set_children(axes._realViewLim) self.axes = axes self.mode = mode self.pad = pad def __str__(self): return ("{}(\n" "{},\n" "{},\n" "{})" .format(type(self).__name__, mtransforms._indent_str(self.axes), mtransforms._indent_str(self.pad), mtransforms._indent_str(repr(self.mode)))) def get_matrix(self): if self._invalid: if self.mode == 'rlabel': angle = ( np.deg2rad(self.axes.get_rlabel_position()) * self.axes.get_theta_direction() + self.axes.get_theta_offset() ) else: if self.mode == 'min': angle = self.axes._realViewLim.xmin elif self.mode == 'max': angle = self.axes._realViewLim.xmax if self.mode in ('rlabel', 'min'): padx = np.cos(angle - np.pi / 2) pady = np.sin(angle - np.pi / 2) else: padx = np.cos(angle + np.pi / 2) pady = np.sin(angle + np.pi / 2) self._t = (self.pad * padx / 72, self.pad * pady / 72) return mtransforms.ScaledTranslation.get_matrix(self)
[docs]class RadialTick(maxis.YTick): """ A radial-axis tick. This subclass of `YTick` provides radial ticks with some small modification to their re-positioning such that ticks are rotated based on axes limits. This results in ticks that are correctly perpendicular to the spine. Labels are also rotated to be perpendicular to the spine, when 'auto' rotation is enabled. """ def _get_text1(self): t = super(RadialTick, self)._get_text1() t.set_rotation_mode('anchor') return t def _get_text2(self): t = super(RadialTick, self)._get_text2() t.set_rotation_mode('anchor') return t def _determine_anchor(self, mode, angle, start): # Note: angle is the (spine angle - 90) because it's used for the tick # & text setup, so all numbers below are -90 from (normed) spine angle. if mode == 'auto': if start: if -90 <= angle <= 90: return 'left', 'center' else: return 'right', 'center' else: if -90 <= angle <= 90: return 'right', 'center' else: return 'left', 'center' else: if start: if angle < -68.5: return 'center', 'top' elif angle < -23.5: return 'left', 'top' elif angle < 22.5: return 'left', 'center' elif angle < 67.5: return 'left', 'bottom' elif angle < 112.5: return 'center', 'bottom' elif angle < 157.5: return 'right', 'bottom' elif angle < 202.5: return 'right', 'center' elif angle < 247.5: return 'right', 'top' else: return 'center', 'top' else: if angle < -68.5: return 'center', 'bottom' elif angle < -23.5: return 'right', 'bottom' elif angle < 22.5: return 'right', 'center' elif angle < 67.5: return 'right', 'top' elif angle < 112.5: return 'center', 'top' elif angle < 157.5: return 'left', 'top' elif angle < 202.5: return 'left', 'center' elif angle < 247.5: return 'left', 'bottom' else: return 'center', 'bottom'
[docs] def update_position(self, loc): super(RadialTick, self).update_position(loc) axes = self.axes thetamin = axes.get_thetamin() thetamax = axes.get_thetamax() direction = axes.get_theta_direction() offset_rad = axes.get_theta_offset() offset = np.rad2deg(offset_rad) full = _is_full_circle_deg(thetamin, thetamax) if full: angle = (axes.get_rlabel_position() * direction + offset) % 360 - 90 tick_angle = 0 if angle > 90: text_angle = angle - 180 elif angle < -90: text_angle = angle + 180 else: text_angle = angle else: angle = (thetamin * direction + offset) % 360 - 90 if direction > 0: tick_angle = np.deg2rad(angle) else: tick_angle = np.deg2rad(angle + 180) if angle > 90: text_angle = angle - 180 elif angle < -90: text_angle = angle + 180 else: text_angle = angle mode, user_angle = self._labelrotation if mode == 'auto': text_angle += user_angle else: text_angle = user_angle if self.label1On: if full: ha = self.label1.get_ha() va = self.label1.get_va() else: ha, va = self._determine_anchor(mode, angle, direction > 0) self.label1.set_ha(ha) self.label1.set_va(va) self.label1.set_rotation(text_angle) if self.tick1On: marker = self.tick1line.get_marker() if marker == mmarkers.TICKLEFT: trans = (mtransforms.Affine2D() .scale(1.0, 1.0) .rotate(tick_angle)) elif marker == '_': trans = (mtransforms.Affine2D() .scale(1.0, 1.0) .rotate(tick_angle + np.pi / 2)) elif marker == mmarkers.TICKRIGHT: trans = (mtransforms.Affine2D() .scale(-1.0, 1.0) .rotate(tick_angle)) else: # Don't modify custom tick line markers. trans = self.tick1line._marker._transform self.tick1line._marker._transform = trans if full: self.label2On = False self.tick2On = False else: angle = (thetamax * direction + offset) % 360 - 90 if direction > 0: tick_angle = np.deg2rad(angle) else: tick_angle = np.deg2rad(angle + 180) if angle > 90: text_angle = angle - 180 elif angle < -90: text_angle = angle + 180 else: text_angle = angle mode, user_angle = self._labelrotation if mode == 'auto': text_angle += user_angle else: text_angle = user_angle if self.label2On: ha, va = self._determine_anchor(mode, angle, direction < 0) self.label2.set_ha(ha) self.label2.set_va(va) self.label2.set_rotation(text_angle) if self.tick2On: marker = self.tick2line.get_marker() if marker == mmarkers.TICKLEFT: trans = (mtransforms.Affine2D() .scale(1.0, 1.0) .rotate(tick_angle)) elif marker == '_': trans = (mtransforms.Affine2D() .scale(1.0, 1.0) .rotate(tick_angle + np.pi / 2)) elif marker == mmarkers.TICKRIGHT: trans = (mtransforms.Affine2D() .scale(-1.0, 1.0) .rotate(tick_angle)) else: # Don't modify custom tick line markers. trans = self.tick2line._marker._transform self.tick2line._marker._transform = trans
[docs]class RadialAxis(maxis.YAxis): """ A radial Axis. This overrides certain properties of a `YAxis` to provide special-casing for a radial axis. """ __name__ = 'radialaxis' axis_name = 'radius' def __init__(self, *args, **kwargs): super(RadialAxis, self).__init__(*args, **kwargs) self.sticky_edges.y.append(0) def _get_tick(self, major): if major: tick_kw = self._major_tick_kw else: tick_kw = self._minor_tick_kw return RadialTick(self.axes, 0, '', major=major, **tick_kw) def _wrap_locator_formatter(self): self.set_major_locator(RadialLocator(self.get_major_locator(), self.axes)) self.isDefault_majloc = True
[docs] def cla(self): super(RadialAxis, self).cla() self.set_ticks_position('none') self._wrap_locator_formatter()
def _set_scale(self, value, **kwargs): super(RadialAxis, self)._set_scale(value, **kwargs) self._wrap_locator_formatter()
def _is_full_circle_deg(thetamin, thetamax): """ Determine if a wedge (in degrees) spans the full circle. The condition is derived from :class:`~matplotlib.patches.Wedge`. """ return abs(abs(thetamax - thetamin) - 360.0) < 1e-12 def _is_full_circle_rad(thetamin, thetamax): """ Determine if a wedge (in radians) spans the full circle. The condition is derived from :class:`~matplotlib.patches.Wedge`. """ return abs(abs(thetamax - thetamin) - 2 * np.pi) < 1.74e-14 class _WedgeBbox(mtransforms.Bbox): """ Transform (theta,r) wedge Bbox into axes bounding box. Parameters ---------- center : tuple of float Center of the wedge viewLim : `~matplotlib.transforms.Bbox` Bbox determining the boundaries of the wedge originLim : `~matplotlib.transforms.Bbox` Bbox determining the origin for the wedge, if different from *viewLim* """ def __init__(self, center, viewLim, originLim, **kwargs): mtransforms.Bbox.__init__(self, np.array([[0.0, 0.0], [1.0, 1.0]], np.float), **kwargs) self._center = center self._viewLim = viewLim self._originLim = originLim self.set_children(viewLim, originLim) def __str__(self): return ("{}(\n" "{},\n" "{},\n" "{})" .format(type(self).__name__, mtransforms._indent_str(self._center), mtransforms._indent_str(self._viewLim), mtransforms._indent_str(self._originLim))) def get_points(self): if self._invalid: points = self._viewLim.get_points().copy() # Scale angular limits to work with Wedge. points[:, 0] *= 180 / np.pi if points[0, 0] > points[1, 0]: points[:, 0] = points[::-1, 0] # Scale radial limits based on origin radius. points[:, 1] -= self._originLim.y0 # Scale radial limits to match axes limits. rscale = 0.5 / points[1, 1] points[:, 1] *= rscale width = min(points[1, 1] - points[0, 1], 0.5) # Generate bounding box for wedge. wedge = mpatches.Wedge(self._center, points[1, 1], points[0, 0], points[1, 0], width=width) self.update_from_path(wedge.get_path()) # Ensure equal aspect ratio. w, h = self._points[1] - self._points[0] if h < w: deltah = (w - h) / 2.0 deltaw = 0.0 elif w < h: deltah = 0.0 deltaw = (h - w) / 2.0 else: deltah = 0.0 deltaw = 0.0 self._points += np.array([[-deltaw, -deltah], [deltaw, deltah]]) self._invalid = 0 return self._points get_points.__doc__ = mtransforms.Bbox.get_points.__doc__
[docs]class PolarAxes(Axes): """ A polar graph projection, where the input dimensions are *theta*, *r*. Theta starts pointing east and goes anti-clockwise. """ name = 'polar' def __init__(self, *args, **kwargs): """ Create a new Polar Axes for a polar plot. """ self._default_theta_offset = kwargs.pop('theta_offset', 0) self._default_theta_direction = kwargs.pop('theta_direction', 1) self._default_rlabel_position = np.deg2rad( kwargs.pop('rlabel_position', 22.5)) Axes.__init__(self, *args, **kwargs) self.use_sticky_edges = True self.set_aspect('equal', adjustable='box', anchor='C') self.cla() __init__.__doc__ = Axes.__init__.__doc__
[docs] def cla(self): Axes.cla(self) self.title.set_y(1.05) start = self.spines.get('start', None) if start: start.set_visible(False) end = self.spines.get('end', None) if end: end.set_visible(False) self.set_xlim(0.0, 2 * np.pi) self.grid(rcParams['polaraxes.grid']) inner = self.spines.get('inner', None) if inner: inner.set_visible(False) self.set_rorigin(None) self.set_theta_offset(self._default_theta_offset) self.set_theta_direction(self._default_theta_direction)
def _init_axis(self): "move this out of __init__ because non-separable axes don't use it" self.xaxis = ThetaAxis(self) self.yaxis = RadialAxis(self) # Calling polar_axes.xaxis.cla() or polar_axes.xaxis.cla() # results in weird artifacts. Therefore we disable this for # now. # self.spines['polar'].register_axis(self.yaxis) self._update_transScale() def _set_lim_and_transforms(self): # A view limit where the minimum radius can be locked if the user # specifies an alternate origin. self._originViewLim = mtransforms.LockableBbox(self.viewLim) # Handle angular offset and direction. self._direction = mtransforms.Affine2D() \ .scale(self._default_theta_direction, 1.0) self._theta_offset = mtransforms.Affine2D() \ .translate(self._default_theta_offset, 0.0) self.transShift = mtransforms.composite_transform_factory( self._direction, self._theta_offset) # A view limit shifted to the correct location after accounting for # orientation and offset. self._realViewLim = mtransforms.TransformedBbox(self.viewLim, self.transShift) # Transforms the x and y axis separately by a scale factor # It is assumed that this part will have non-linear components self.transScale = mtransforms.TransformWrapper( mtransforms.IdentityTransform()) # Scale view limit into a bbox around the selected wedge. This may be # smaller than the usual unit axes rectangle if not plotting the full # circle. self.axesLim = _WedgeBbox((0.5, 0.5), self._realViewLim, self._originViewLim) # Scale the wedge to fill the axes. self.transWedge = mtransforms.BboxTransformFrom(self.axesLim) # Scale the axes to fill the figure. self.transAxes = mtransforms.BboxTransformTo(self.bbox) # A (possibly non-linear) projection on the (already scaled) # data. This one is aware of rmin self.transProjection = self.PolarTransform( self, _apply_theta_transforms=False) # Add dependency on rorigin. self.transProjection.set_children(self._originViewLim) # An affine transformation on the data, generally to limit the # range of the axes self.transProjectionAffine = self.PolarAffine(self.transScale, self._originViewLim) # The complete data transformation stack -- from data all the # way to display coordinates self.transData = ( self.transScale + self.transShift + self.transProjection + (self.transProjectionAffine + self.transWedge + self.transAxes)) # This is the transform for theta-axis ticks. It is # equivalent to transData, except it always puts r == 0.0 and r == 1.0 # at the edge of the axis circles. self._xaxis_transform = ( mtransforms.blended_transform_factory( mtransforms.IdentityTransform(), mtransforms.BboxTransformTo(self.viewLim)) + self.transData) # The theta labels are flipped along the radius, so that text 1 is on # the outside by default. This should work the same as before. flipr_transform = mtransforms.Affine2D() \ .translate(0.0, -0.5) \ .scale(1.0, -1.0) \ .translate(0.0, 0.5) self._xaxis_text_transform = flipr_transform + self._xaxis_transform # This is the transform for r-axis ticks. It scales the theta # axis so the gridlines from 0.0 to 1.0, now go from thetamin to # thetamax. self._yaxis_transform = ( mtransforms.blended_transform_factory( mtransforms.BboxTransformTo(self.viewLim), mtransforms.IdentityTransform()) + self.transData) # The r-axis labels are put at an angle and padded in the r-direction self._r_label_position = mtransforms.Affine2D() \ .translate(self._default_rlabel_position, 0.0) self._yaxis_text_transform = mtransforms.TransformWrapper( self._r_label_position + self.transData)
[docs] def get_xaxis_transform(self, which='grid'): if which not in ['tick1', 'tick2', 'grid']: raise ValueError( "'which' must be one of 'tick1', 'tick2', or 'grid'") return self._xaxis_transform
[docs] def get_xaxis_text1_transform(self, pad): return self._xaxis_text_transform, 'center', 'center'
[docs] def get_xaxis_text2_transform(self, pad): return self._xaxis_text_transform, 'center', 'center'
[docs] def get_yaxis_transform(self, which='grid'): if which in ('tick1', 'tick2'): return self._yaxis_text_transform elif which == 'grid': return self._yaxis_transform else: raise ValueError( "'which' must be one of 'tick1', 'tick2', or 'grid'")
[docs] def get_yaxis_text1_transform(self, pad): thetamin, thetamax = self._realViewLim.intervalx if _is_full_circle_rad(thetamin, thetamax): return self._yaxis_text_transform, 'bottom', 'left' elif self.get_theta_direction() > 0: halign = 'left' pad_shift = _ThetaShift(self, pad, 'min') else: halign = 'right' pad_shift = _ThetaShift(self, pad, 'max') return self._yaxis_text_transform + pad_shift, 'center', halign
[docs] def get_yaxis_text2_transform(self, pad): if self.get_theta_direction() > 0: halign = 'right' pad_shift = _ThetaShift(self, pad, 'max') else: halign = 'left' pad_shift = _ThetaShift(self, pad, 'min') return self._yaxis_text_transform + pad_shift, 'center', halign
[docs] def draw(self, *args, **kwargs): thetamin, thetamax = np.rad2deg(self._realViewLim.intervalx) if thetamin > thetamax: thetamin, thetamax = thetamax, thetamin rmin, rmax = self._realViewLim.intervaly - self.get_rorigin() if isinstance(self.patch, mpatches.Wedge): # Backwards-compatibility: Any subclassed Axes might override the # patch to not be the Wedge that PolarAxes uses. center = self.transWedge.transform_point((0.5, 0.5)) self.patch.set_center(center) self.patch.set_theta1(thetamin) self.patch.set_theta2(thetamax) edge, _ = self.transWedge.transform_point((1, 0)) radius = edge - center[0] width = min(radius * (rmax - rmin) / rmax, radius) self.patch.set_radius(radius) self.patch.set_width(width) inner_width = radius - width inner = self.spines.get('inner', None) if inner: inner.set_visible(inner_width != 0.0) visible = not _is_full_circle_deg(thetamin, thetamax) # For backwards compatibility, any subclassed Axes might override the # spines to not include start/end that PolarAxes uses. start = self.spines.get('start', None) end = self.spines.get('end', None) if start: start.set_visible(visible) if end: end.set_visible(visible) if visible: yaxis_text_transform = self._yaxis_transform else: yaxis_text_transform = self._r_label_position + self.transData if self._yaxis_text_transform != yaxis_text_transform: self._yaxis_text_transform.set(yaxis_text_transform) self.yaxis.reset_ticks() self.yaxis.set_clip_path(self.patch) Axes.draw(self, *args, **kwargs)
def _gen_axes_patch(self): return mpatches.Wedge((0.5, 0.5), 0.5, 0.0, 360.0) def _gen_axes_spines(self): spines = OrderedDict([ ('polar', mspines.Spine.arc_spine(self, 'top', (0.5, 0.5), 0.5, 0.0, 360.0)), ('start', mspines.Spine.linear_spine(self, 'left')), ('end', mspines.Spine.linear_spine(self, 'right')), ('inner', mspines.Spine.arc_spine(self, 'bottom', (0.5, 0.5), 0.0, 0.0, 360.0)) ]) spines['polar'].set_transform(self.transWedge + self.transAxes) spines['inner'].set_transform(self.transWedge + self.transAxes) spines['start'].set_transform(self._yaxis_transform) spines['end'].set_transform(self._yaxis_transform) return spines
[docs] def set_thetamax(self, thetamax): self.viewLim.x1 = np.deg2rad(thetamax)
[docs] def get_thetamax(self): return np.rad2deg(self.viewLim.xmax)
[docs] def set_thetamin(self, thetamin): self.viewLim.x0 = np.deg2rad(thetamin)
[docs] def get_thetamin(self): return np.rad2deg(self.viewLim.xmin)
[docs] def set_thetalim(self, *args, **kwargs): if 'thetamin' in kwargs: kwargs['xmin'] = np.deg2rad(kwargs.pop('thetamin')) if 'thetamax' in kwargs: kwargs['xmax'] = np.deg2rad(kwargs.pop('thetamax')) return tuple(np.rad2deg(self.set_xlim(*args, **kwargs)))
[docs] def set_theta_offset(self, offset): """ Set the offset for the location of 0 in radians. """ mtx = self._theta_offset.get_matrix() mtx[0, 2] = offset self._theta_offset.invalidate()
[docs] def get_theta_offset(self): """ Get the offset for the location of 0 in radians. """ return self._theta_offset.get_matrix()[0, 2]
[docs] def set_theta_zero_location(self, loc, offset=0.0): """ Sets the location of theta's zero. (Calls set_theta_offset with the correct value in radians under the hood.) loc : str May be one of "N", "NW", "W", "SW", "S", "SE", "E", or "NE". offset : float, optional An offset in degrees to apply from the specified `loc`. **Note:** this offset is *always* applied counter-clockwise regardless of the direction setting. """ mapping = { 'N': np.pi * 0.5, 'NW': np.pi * 0.75, 'W': np.pi, 'SW': np.pi * 1.25, 'S': np.pi * 1.5, 'SE': np.pi * 1.75, 'E': 0, 'NE': np.pi * 0.25} return self.set_theta_offset(mapping[loc] + np.deg2rad(offset))
[docs] def set_theta_direction(self, direction): """ Set the direction in which theta increases. clockwise, -1: Theta increases in the clockwise direction counterclockwise, anticlockwise, 1: Theta increases in the counterclockwise direction """ mtx = self._direction.get_matrix() if direction in ('clockwise',): mtx[0, 0] = -1 elif direction in ('counterclockwise', 'anticlockwise'): mtx[0, 0] = 1 elif direction in (1, -1): mtx[0, 0] = direction else: raise ValueError( "direction must be 1, -1, clockwise or counterclockwise") self._direction.invalidate()
[docs] def get_theta_direction(self): """ Get the direction in which theta increases. -1: Theta increases in the clockwise direction 1: Theta increases in the counterclockwise direction """ return self._direction.get_matrix()[0, 0]
[docs] def set_rmax(self, rmax): self.viewLim.y1 = rmax
[docs] def get_rmax(self): return self.viewLim.ymax
[docs] def set_rmin(self, rmin): self.viewLim.y0 = rmin
[docs] def get_rmin(self): return self.viewLim.ymin
[docs] def set_rorigin(self, rorigin): self._originViewLim.locked_y0 = rorigin
[docs] def get_rorigin(self): return self._originViewLim.y0
[docs] def set_rlim(self, *args, **kwargs): if 'rmin' in kwargs: kwargs['ymin'] = kwargs.pop('rmin') if 'rmax' in kwargs: kwargs['ymax'] = kwargs.pop('rmax') return self.set_ylim(*args, **kwargs)
[docs] def get_rlabel_position(self): """ Returns ------- float The theta position of the radius labels in degrees. """ return np.rad2deg(self._r_label_position.get_matrix()[0, 2])
[docs] def set_rlabel_position(self, value): """Updates the theta position of the radius labels. Parameters ---------- value : number The angular position of the radius labels in degrees. """ self._r_label_position.clear().translate(np.deg2rad(value), 0.0)
[docs] def set_yscale(self, *args, **kwargs): Axes.set_yscale(self, *args, **kwargs) self.yaxis.set_major_locator( self.RadialLocator(self.yaxis.get_major_locator(), self))
[docs] def set_rscale(self, *args, **kwargs): return Axes.set_yscale(self, *args, **kwargs)
[docs] def set_rticks(self, *args, **kwargs): return Axes.set_yticks(self, *args, **kwargs)
[docs] @docstring.dedent_interpd def set_thetagrids(self, angles, labels=None, frac=None, fmt=None, **kwargs): """ Set the angles at which to place the theta grids (these gridlines are equal along the theta dimension). *angles* is in degrees. *labels*, if not None, is a ``len(angles)`` list of strings of the labels to use at each angle. If *labels* is None, the labels will be ``fmt %% angle`` *frac* is the fraction of the polar axes radius at which to place the label (1 is the edge). e.g., 1.05 is outside the axes and 0.95 is inside the axes. Return value is a list of tuples (*line*, *label*), where *line* is :class:`~matplotlib.lines.Line2D` instances and the *label* is :class:`~matplotlib.text.Text` instances. kwargs are optional text properties for the labels: %(Text)s ACCEPTS: sequence of floats """ if frac is not None: cbook.warn_deprecated('2.1', name='frac', obj_type='parameter', alternative='tick padding via ' 'Axes.tick_params') # Make sure we take into account unitized data angles = self.convert_yunits(angles) angles = np.deg2rad(angles) self.set_xticks(angles) if labels is not None: self.set_xticklabels(labels) elif fmt is not None: self.xaxis.set_major_formatter(mticker.FormatStrFormatter(fmt)) for t in self.xaxis.get_ticklabels(): t.update(kwargs) return self.xaxis.get_ticklines(), self.xaxis.get_ticklabels()
[docs] @docstring.dedent_interpd def set_rgrids(self, radii, labels=None, angle=None, fmt=None, **kwargs): """ Set the radial locations and labels of the *r* grids. The labels will appear at radial distances *radii* at the given *angle* in degrees. *labels*, if not None, is a ``len(radii)`` list of strings of the labels to use at each radius. If *labels* is None, the built-in formatter will be used. Return value is a list of tuples (*line*, *label*), where *line* is :class:`~matplotlib.lines.Line2D` instances and the *label* is :class:`~matplotlib.text.Text` instances. kwargs are optional text properties for the labels: %(Text)s ACCEPTS: sequence of floats """ # Make sure we take into account unitized data radii = self.convert_xunits(radii) radii = np.asarray(radii) self.set_yticks(radii) if labels is not None: self.set_yticklabels(labels) elif fmt is not None: self.yaxis.set_major_formatter(mticker.FormatStrFormatter(fmt)) if angle is None: angle = self.get_rlabel_position() self.set_rlabel_position(angle) for t in self.yaxis.get_ticklabels(): t.update(kwargs) return self.yaxis.get_gridlines(), self.yaxis.get_ticklabels()
[docs] def set_xscale(self, scale, *args, **kwargs): if scale != 'linear': raise NotImplementedError( "You can not set the xscale on a polar plot.")
[docs] def format_coord(self, theta, r): """ Return a format string formatting the coordinate using Unicode characters. """ if theta < 0: theta += 2 * np.pi theta /= np.pi return ('\N{GREEK SMALL LETTER THETA}=%0.3f\N{GREEK SMALL LETTER PI} ' '(%0.3f\N{DEGREE SIGN}), r=%0.3f') % (theta, theta * 180.0, r)
[docs] def get_data_ratio(self): ''' Return the aspect ratio of the data itself. For a polar plot, this should always be 1.0 ''' return 1.0
# # # Interactive panning
[docs] def can_zoom(self): """ Return *True* if this axes supports the zoom box button functionality. Polar axes do not support zoom boxes. """ return False
[docs] def can_pan(self): """ Return *True* if this axes supports the pan/zoom button functionality. For polar axes, this is slightly misleading. Both panning and zooming are performed by the same button. Panning is performed in azimuth while zooming is done along the radial. """ return True
[docs] def start_pan(self, x, y, button): angle = np.deg2rad(self.get_rlabel_position()) mode = '' if button == 1: epsilon = np.pi / 45.0 t, r = self.transData.inverted().transform_point((x, y)) if t >= angle - epsilon and t <= angle + epsilon: mode = 'drag_r_labels' elif button == 3: mode = 'zoom' self._pan_start = cbook.Bunch( rmax=self.get_rmax(), trans=self.transData.frozen(), trans_inverse=self.transData.inverted().frozen(), r_label_angle=self.get_rlabel_position(), x=x, y=y, mode=mode)
[docs] def end_pan(self): del self._pan_start
[docs] def drag_pan(self, button, key, x, y): p = self._pan_start if p.mode == 'drag_r_labels': startt, startr = p.trans_inverse.transform_point((p.x, p.y)) t, r = p.trans_inverse.transform_point((x, y)) # Deal with theta dt0 = t - startt dt1 = startt - t if abs(dt1) < abs(dt0): dt = abs(dt1) * np.sign(dt0) * -1.0 else: dt = dt0 * -1.0 dt = (dt / np.pi) * 180.0 self.set_rlabel_position(p.r_label_angle - dt) trans, vert1, horiz1 = self.get_yaxis_text1_transform(0.0) trans, vert2, horiz2 = self.get_yaxis_text2_transform(0.0) for t in self.yaxis.majorTicks + self.yaxis.minorTicks: t.label1.set_va(vert1) t.label1.set_ha(horiz1) t.label2.set_va(vert2) t.label2.set_ha(horiz2) elif p.mode == 'zoom': startt, startr = p.trans_inverse.transform_point((p.x, p.y)) t, r = p.trans_inverse.transform_point((x, y)) # Deal with r scale = r / startr self.set_rmax(p.rmax / scale)
# to keep things all self contained, we can put aliases to the Polar classes # defined above. This isn't strictly necessary, but it makes some of the # code more readable (and provides a backwards compatible Polar API) PolarAxes.PolarTransform = PolarTransform PolarAxes.PolarAffine = PolarAffine PolarAxes.InvertedPolarTransform = InvertedPolarTransform PolarAxes.ThetaFormatter = ThetaFormatter PolarAxes.RadialLocator = RadialLocator PolarAxes.ThetaLocator = ThetaLocator # These are a couple of aborted attempts to project a polar plot using # cubic bezier curves. # def transform_path(self, path): # twopi = 2.0 * np.pi # halfpi = 0.5 * np.pi # vertices = path.vertices # t0 = vertices[0:-1, 0] # t1 = vertices[1: , 0] # td = np.where(t1 > t0, t1 - t0, twopi - (t0 - t1)) # maxtd = td.max() # interpolate = np.ceil(maxtd / halfpi) # if interpolate > 1.0: # vertices = self.interpolate(vertices, interpolate) # vertices = self.transform(vertices) # result = np.zeros((len(vertices) * 3 - 2, 2), float) # codes = mpath.Path.CURVE4 * np.ones((len(vertices) * 3 - 2, ), # mpath.Path.code_type) # result[0] = vertices[0] # codes[0] = mpath.Path.MOVETO # kappa = 4.0 * ((np.sqrt(2.0) - 1.0) / 3.0) # kappa = 0.5 # p0 = vertices[0:-1] # p1 = vertices[1: ] # x0 = p0[:, 0:1] # y0 = p0[:, 1: ] # b0 = ((y0 - x0) - y0) / ((x0 + y0) - x0) # a0 = y0 - b0*x0 # x1 = p1[:, 0:1] # y1 = p1[:, 1: ] # b1 = ((y1 - x1) - y1) / ((x1 + y1) - x1) # a1 = y1 - b1*x1 # x = -(a0-a1) / (b0-b1) # y = a0 + b0*x # xk = (x - x0) * kappa + x0 # yk = (y - y0) * kappa + y0 # result[1::3, 0:1] = xk # result[1::3, 1: ] = yk # xk = (x - x1) * kappa + x1 # yk = (y - y1) * kappa + y1 # result[2::3, 0:1] = xk # result[2::3, 1: ] = yk # result[3::3] = p1 # print(vertices[-2:]) # print(result[-2:]) # return mpath.Path(result, codes) # twopi = 2.0 * np.pi # halfpi = 0.5 * np.pi # vertices = path.vertices # t0 = vertices[0:-1, 0] # t1 = vertices[1: , 0] # td = np.where(t1 > t0, t1 - t0, twopi - (t0 - t1)) # maxtd = td.max() # interpolate = np.ceil(maxtd / halfpi) # print("interpolate", interpolate) # if interpolate > 1.0: # vertices = self.interpolate(vertices, interpolate) # result = np.zeros((len(vertices) * 3 - 2, 2), float) # codes = mpath.Path.CURVE4 * np.ones((len(vertices) * 3 - 2, ), # mpath.Path.code_type) # result[0] = vertices[0] # codes[0] = mpath.Path.MOVETO # kappa = 4.0 * ((np.sqrt(2.0) - 1.0) / 3.0) # tkappa = np.arctan(kappa) # hyp_kappa = np.sqrt(kappa*kappa + 1.0) # t0 = vertices[0:-1, 0] # t1 = vertices[1: , 0] # r0 = vertices[0:-1, 1] # r1 = vertices[1: , 1] # td = np.where(t1 > t0, t1 - t0, twopi - (t0 - t1)) # td_scaled = td / (np.pi * 0.5) # rd = r1 - r0 # r0kappa = r0 * kappa * td_scaled # r1kappa = r1 * kappa * td_scaled # ravg_kappa = ((r1 + r0) / 2.0) * kappa * td_scaled # result[1::3, 0] = t0 + (tkappa * td_scaled) # result[1::3, 1] = r0*hyp_kappa # # result[1::3, 1] = r0 / np.cos(tkappa * td_scaled) # # np.sqrt(r0*r0 + ravg_kappa*ravg_kappa) # result[2::3, 0] = t1 - (tkappa * td_scaled) # result[2::3, 1] = r1*hyp_kappa # # result[2::3, 1] = r1 / np.cos(tkappa * td_scaled) # # np.sqrt(r1*r1 + ravg_kappa*ravg_kappa) # result[3::3, 0] = t1 # result[3::3, 1] = r1 # print(vertices[:6], result[:6], t0[:6], t1[:6], td[:6], # td_scaled[:6], tkappa) # result = self.transform(result) # return mpath.Path(result, codes) # transform_path_non_affine = transform_path