Source code for mpl_toolkits.axisartist.floating_axes

"""
An experimental support for curvilinear grid.
"""

# TODO :
# see if tick_iterator method can be simplified by reusing the parent method.

import functools

import numpy as np

import matplotlib.patches as mpatches
from matplotlib.path import Path
from matplotlib.transforms import IdentityTransform
import matplotlib.axes as maxes

from mpl_toolkits.axes_grid1.parasite_axes import host_axes_class_factory

from . import axislines, grid_helper_curvelinear
from .axis_artist import AxisArtist
from .grid_finder import ExtremeFinderSimple


[docs]class FloatingAxisArtistHelper( grid_helper_curvelinear.FloatingAxisArtistHelper): pass
[docs]class FixedAxisArtistHelper(grid_helper_curvelinear.FloatingAxisArtistHelper): def __init__(self, grid_helper, side, nth_coord_ticks=None): """ nth_coord = along which coordinate value varies. nth_coord = 0 -> x axis, nth_coord = 1 -> y axis """ value, nth_coord = grid_helper.get_data_boundary(side) super().__init__(grid_helper, nth_coord, value, axis_direction=side) if nth_coord_ticks is None: nth_coord_ticks = nth_coord self.nth_coord_ticks = nth_coord_ticks self.value = value self.grid_helper = grid_helper self._side = side
[docs] def update_lim(self, axes): self.grid_helper.update_lim(axes) self.grid_info = self.grid_helper.grid_info
[docs] def get_tick_iterators(self, axes): """tick_loc, tick_angle, tick_label, (optionally) tick_label""" grid_finder = self.grid_helper.grid_finder lat_levs, lat_n, lat_factor = self.grid_info["lat_info"] lon_levs, lon_n, lon_factor = self.grid_info["lon_info"] lon_levs, lat_levs = np.asarray(lon_levs), np.asarray(lat_levs) if lat_factor is not None: yy0 = lat_levs / lat_factor dy = 0.001 / lat_factor else: yy0 = lat_levs dy = 0.001 if lon_factor is not None: xx0 = lon_levs / lon_factor dx = 0.001 / lon_factor else: xx0 = lon_levs dx = 0.001 extremes = self.grid_helper._extremes xmin, xmax = sorted(extremes[:2]) ymin, ymax = sorted(extremes[2:]) def transform_xy(x, y): x1, y1 = grid_finder.transform_xy(x, y) x2, y2 = axes.transData.transform(np.array([x1, y1]).T).T return x2, y2 if self.nth_coord == 0: mask = (ymin <= yy0) & (yy0 <= ymax) yy0 = yy0[mask] xx0 = np.full_like(yy0, self.value) xx1, yy1 = transform_xy(xx0, yy0) xx00 = xx0.astype(float, copy=True) xx00[xx0 + dx > xmax] -= dx xx1a, yy1a = transform_xy(xx00, yy0) xx1b, yy1b = transform_xy(xx00 + dx, yy0) yy00 = yy0.astype(float, copy=True) yy00[yy0 + dy > ymax] -= dy xx2a, yy2a = transform_xy(xx0, yy00) xx2b, yy2b = transform_xy(xx0, yy00 + dy) labels = self.grid_info["lat_labels"] labels = [l for l, m in zip(labels, mask) if m] elif self.nth_coord == 1: mask = (xmin <= xx0) & (xx0 <= xmax) xx0 = xx0[mask] yy0 = np.full_like(xx0, self.value) xx1, yy1 = transform_xy(xx0, yy0) yy00 = yy0.astype(float, copy=True) yy00[yy0 + dy > ymax] -= dy xx1a, yy1a = transform_xy(xx0, yy00) xx1b, yy1b = transform_xy(xx0, yy00 + dy) xx00 = xx0.astype(float, copy=True) xx00[xx0 + dx > xmax] -= dx xx2a, yy2a = transform_xy(xx00, yy0) xx2b, yy2b = transform_xy(xx00 + dx, yy0) labels = self.grid_info["lon_labels"] labels = [l for l, m in zip(labels, mask) if m] def f1(): dd = np.arctan2(yy1b - yy1a, xx1b - xx1a) # angle normal dd2 = np.arctan2(yy2b - yy2a, xx2b - xx2a) # angle tangent mm = (yy1b - yy1a == 0) & (xx1b - xx1a == 0) # mask not defined dd dd[mm] = dd2[mm] + np.pi / 2 tick_to_axes = self.get_tick_transform(axes) - axes.transAxes for x, y, d, d2, lab in zip(xx1, yy1, dd, dd2, labels): c2 = tick_to_axes.transform((x, y)) delta = 0.00001 if 0-delta <= c2[0] <= 1+delta and 0-delta <= c2[1] <= 1+delta: d1, d2 = np.rad2deg([d, d2]) yield [x, y], d1, d2, lab return f1(), iter([])
[docs] def get_line(self, axes): self.update_lim(axes) k, v = dict(left=("lon_lines0", 0), right=("lon_lines0", 1), bottom=("lat_lines0", 0), top=("lat_lines0", 1))[self._side] xx, yy = self.grid_info[k][v] return Path(np.column_stack([xx, yy]))
[docs]class ExtremeFinderFixed(ExtremeFinderSimple): def __init__(self, extremes): self._extremes = extremes def __call__(self, transform_xy, x1, y1, x2, y2): """ get extreme values. x1, y1, x2, y2 in image coordinates (0-based) nx, ny : number of division in each axis """ return self._extremes
[docs]class GridHelperCurveLinear(grid_helper_curvelinear.GridHelperCurveLinear): def __init__(self, aux_trans, extremes, grid_locator1=None, grid_locator2=None, tick_formatter1=None, tick_formatter2=None): # docstring inherited self._extremes = extremes extreme_finder = ExtremeFinderFixed(extremes) super().__init__(aux_trans, extreme_finder, grid_locator1=grid_locator1, grid_locator2=grid_locator2, tick_formatter1=tick_formatter1, tick_formatter2=tick_formatter2)
[docs] def get_data_boundary(self, side): """ return v=0, nth=1 """ lon1, lon2, lat1, lat2 = self._extremes return dict(left=(lon1, 0), right=(lon2, 0), bottom=(lat1, 1), top=(lat2, 1))[side]
[docs] def new_fixed_axis(self, loc, nth_coord=None, axis_direction=None, offset=None, axes=None): if axes is None: axes = self.axes if axis_direction is None: axis_direction = loc # This is not the same as the FixedAxisArtistHelper class used by # grid_helper_curvelinear.GridHelperCurveLinear.new_fixed_axis! _helper = FixedAxisArtistHelper( self, loc, nth_coord_ticks=nth_coord) axisline = AxisArtist(axes, _helper, axis_direction=axis_direction) # Perhaps should be moved to the base class? axisline.line.set_clip_on(True) axisline.line.set_clip_box(axisline.axes.bbox) return axisline
# new_floating_axis will inherit the grid_helper's extremes. # def new_floating_axis(self, nth_coord, # value, # axes=None, # axis_direction="bottom" # ): # axis = super(GridHelperCurveLinear, # self).new_floating_axis(nth_coord, # value, axes=axes, # axis_direction=axis_direction) # # set extreme values of the axis helper # if nth_coord == 1: # axis.get_helper().set_extremes(*self._extremes[:2]) # elif nth_coord == 0: # axis.get_helper().set_extremes(*self._extremes[2:]) # return axis def _update_grid(self, x1, y1, x2, y2): if self.grid_info is None: self.grid_info = dict() grid_info = self.grid_info grid_finder = self.grid_finder extremes = grid_finder.extreme_finder(grid_finder.inv_transform_xy, x1, y1, x2, y2) lon_min, lon_max = sorted(extremes[:2]) lat_min, lat_max = sorted(extremes[2:]) lon_levs, lon_n, lon_factor = \ grid_finder.grid_locator1(lon_min, lon_max) lat_levs, lat_n, lat_factor = \ grid_finder.grid_locator2(lat_min, lat_max) grid_info["extremes"] = lon_min, lon_max, lat_min, lat_max # extremes grid_info["lon_info"] = lon_levs, lon_n, lon_factor grid_info["lat_info"] = lat_levs, lat_n, lat_factor grid_info["lon_labels"] = grid_finder.tick_formatter1("bottom", lon_factor, lon_levs) grid_info["lat_labels"] = grid_finder.tick_formatter2("bottom", lat_factor, lat_levs) if lon_factor is None: lon_values = np.asarray(lon_levs[:lon_n]) else: lon_values = np.asarray(lon_levs[:lon_n]/lon_factor) if lat_factor is None: lat_values = np.asarray(lat_levs[:lat_n]) else: lat_values = np.asarray(lat_levs[:lat_n]/lat_factor) lon_lines, lat_lines = grid_finder._get_raw_grid_lines( lon_values[(lon_min < lon_values) & (lon_values < lon_max)], lat_values[(lat_min < lat_values) & (lat_values < lat_max)], lon_min, lon_max, lat_min, lat_max) grid_info["lon_lines"] = lon_lines grid_info["lat_lines"] = lat_lines lon_lines, lat_lines = grid_finder._get_raw_grid_lines( # lon_min, lon_max, lat_min, lat_max) extremes[:2], extremes[2:], *extremes) grid_info["lon_lines0"] = lon_lines grid_info["lat_lines0"] = lat_lines
[docs] def get_gridlines(self, which="major", axis="both"): grid_lines = [] if axis in ["both", "x"]: grid_lines.extend(self.grid_info["lon_lines"]) if axis in ["both", "y"]: grid_lines.extend(self.grid_info["lat_lines"]) return grid_lines
[docs] def get_boundary(self): """ Return (N, 2) array of (x, y) coordinate of the boundary. """ x0, x1, y0, y1 = self._extremes tr = self._aux_trans xx = np.linspace(x0, x1, 100) yy0 = np.full_like(xx, y0) yy1 = np.full_like(xx, y1) yy = np.linspace(y0, y1, 100) xx0 = np.full_like(yy, x0) xx1 = np.full_like(yy, x1) xxx = np.concatenate([xx[:-1], xx1[:-1], xx[-1:0:-1], xx0]) yyy = np.concatenate([yy0[:-1], yy[:-1], yy1[:-1], yy[::-1]]) t = tr.transform(np.array([xxx, yyy]).transpose()) return t
[docs]class FloatingAxesBase: def __init__(self, *args, **kwargs): grid_helper = kwargs.get("grid_helper", None) if grid_helper is None: raise ValueError("FloatingAxes requires grid_helper argument") if not hasattr(grid_helper, "get_boundary"): raise ValueError("grid_helper must implement get_boundary method") self._axes_class_floating.__init__(self, *args, **kwargs) self.set_aspect(1.) self.adjust_axes_lim() def _gen_axes_patch(self): """ Returns the patch used to draw the background of the axes. It is also used as the clipping path for any data elements on the axes. In the standard axes, this is a rectangle, but in other projections it may not be. .. note:: Intended to be overridden by new projection types. """ grid_helper = self.get_grid_helper() t = grid_helper.get_boundary() return mpatches.Polygon(t)
[docs] def cla(self): self._axes_class_floating.cla(self) # HostAxes.cla(self) self.patch.set_transform(self.transData) patch = self._axes_class_floating._gen_axes_patch(self) patch.set_figure(self.figure) patch.set_visible(False) patch.set_transform(self.transAxes) self.patch.set_clip_path(patch) self.gridlines.set_clip_path(patch) self._original_patch = patch
[docs] def adjust_axes_lim(self): grid_helper = self.get_grid_helper() t = grid_helper.get_boundary() x, y = t[:, 0], t[:, 1] xmin, xmax = min(x), max(x) ymin, ymax = min(y), max(y) dx = (xmax-xmin) / 100 dy = (ymax-ymin) / 100 self.set_xlim(xmin-dx, xmax+dx) self.set_ylim(ymin-dy, ymax+dy)
[docs]@functools.lru_cache(None) def floatingaxes_class_factory(axes_class): return type("Floating %s" % axes_class.__name__, (FloatingAxesBase, axes_class), {'_axes_class_floating': axes_class})
FloatingAxes = floatingaxes_class_factory( host_axes_class_factory(axislines.Axes)) FloatingSubplot = maxes.subplot_class_factory(FloatingAxes)