Python Programmers Group

import numpy as np import matplotlib.pyplot as plt from matplotlib.patches import Circle, RegularPolygon from matplotlib.path import Path from matplotlib.projections.polar import PolarAxes from matplotlib.projections import register_projection from matplotlib.spines import Spine from matplotlib.transforms import Affine2D def radar_factory(num_vars, frame='circle'): """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 RadarAxes(PolarAxes): name = 'radar' def init(self, *args, **kwargs): super().init(*args, **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) 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.concatenate((x, [x[0]])) y = np.concatenate((y, [y[0]])) line.set_data(x, y) def set_varlabels(self, labels): self.set_thetagrids(np.degrees(theta), labels) 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=.5, edgecolor="k") else: raise ValueError("unknown value for 'frame': %s" % frame) def draw(self, renderer): """ Draw. If frame is polygon, make gridlines polygon-shaped """ if frame == 'polygon': gridlines = self.yaxis.get_gridlines() for gl in gridlines: gl.get_path()._interpolation_steps = num_vars super().draw(renderer) 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(.5).translate(.5, .5) + self.transAxes) return {'polar': spine} else: raise ValueError("unknown value for 'frame': %s" % frame) register_projection(RadarAxes) return theta data = [['Sulfate', 'Nitrate', 'EC', 'OC1', 'OC2', 'OC3', 'OP', 'CO', 'O3'], ('Basecase', [ [0.88, 0.01, 0.03, 0.03, 0.00, 0.06, 0.01, 0.00, 0.00], [0.07, 0.95, 0.04, 0.05, 0.00, 0.02, 0.01, 0.00, 0.00], [0.01, 0.02, 0.85, 0.19, 0.05, 0.10, 0.00, 0.00, 0.00], [0.02, 0.01, 0.07, 0.01, 0.21, 0.12, 0.98, 0.00, 0.00], [0.01, 0.01, 0.02, 0.71, 0.74, 0.70, 0.00, 0.00, 0.00]])] N = len(data[0]) theta = radar_factory(N, frame='polygon')