Source code for smefit.analyze.spider

# -*- coding: utf-8 -*-
import numpy as np
from matplotlib.patches import Circle, RegularPolygon
from matplotlib.path import Path
from matplotlib.projections import register_projection
from matplotlib.projections.polar import PolarAxes
from matplotlib.spines import Spine
from matplotlib.transforms import Affine2D


[docs] def radar_factory(num_vars, frame="circle"): """ This function is copied from https://matplotlib.org/stable/gallery/specialty_plots/radar_chart.html Create a radar chart with `num_vars` axes. This function creates a RadarAxes projection and registers it. Parameters ---------- num_vars : int Number of variables for radar chart. frame : {'circle', 'polygon'} Shape of frame surrounding axes. """ # calculate evenly-spaced axis angles theta = np.linspace(0, 2 * np.pi, num_vars, endpoint=False) class RadarTransform(PolarAxes.PolarTransform): def transform_path_non_affine(self, path): # Paths with non-unit interpolation steps correspond to gridlines, # in which case we force interpolation (to defeat PolarTransform's # autoconversion to circular arcs). if path._interpolation_steps > 1: path = path.interpolated(num_vars) return Path(self.transform(path.vertices), path.codes) class RadarAxes(PolarAxes): name = "radar" PolarTransform = RadarTransform def __init__(self, *args, **kwargs): super().__init__(*args, aspect="equal", **kwargs) # rotate plot such that the first axis is at the top self.set_theta_zero_location("N") def fill(self, *args, closed=True, **kwargs): """Override fill so that line is closed by default""" return super().fill(closed=closed, *args, **kwargs) def plot(self, *args, **kwargs): """Override plot so that line is closed by default""" lines = super().plot(*args, **kwargs) for line in lines: self._close_line(line) return lines def _close_line(self, line): x, y = line.get_data() # FIXME: markers at x[0], y[0] get doubled-up if x[0] != x[-1]: x = np.append(x, x[0]) y = np.append(y, y[0]) line.set_data(x, y) def set_varlabels(self, labels, fontsize=12): self.set_thetagrids(np.degrees(theta), labels, fontsize=fontsize) def _gen_axes_patch(self): # The Axes patch must be centered at (0.5, 0.5) and of radius 0.5 # in axes coordinates. if frame == "circle": return Circle((0.5, 0.5), 0.5) elif frame == "polygon": return RegularPolygon((0.5, 0.5), num_vars, radius=0.5, edgecolor="k") else: raise ValueError("Unknown value for 'frame': %s" % frame) def _gen_axes_spines(self): if frame == "circle": return super()._gen_axes_spines() elif frame == "polygon": # spine_type must be 'left'/'right'/'top'/'bottom'/'circle'. spine = Spine( axes=self, spine_type="circle", path=Path.unit_regular_polygon(num_vars), ) # unit_regular_polygon gives a polygon of radius 1 centered at # (0, 0) but we want a polygon of radius 0.5 centered at (0.5, # 0.5) in axes coordinates. spine.set_transform( Affine2D().scale(0.5).translate(0.5, 0.5) + self.transAxes ) return {"polar": spine} else: raise ValueError("Unknown value for 'frame': %s" % frame) register_projection(RadarAxes) return theta