Как построить лепестковую диаграмму на python c пятиугольной сеткой?

Question

С помощью matplotlib построен radar chart с пятью метками.

Как изменить сетку диаграммы с окружностей на пятиугольник?

На просторах интернета найден соответствующий код:

        gridlines = ax.yaxis.get_gridlines()
        for gl in gridlines:
            gl.get_path()._interpolation_steps = 5

Однако, это не работает. Даже копируя код из приводимого примера, меняется только форма внешней границы, а внутренняя сетка остается круглой. Для понимания сути вопроса, вот ссылка на "не наш" стэк: Radar spider chart

Полный код программы для примера ниже.

import numpy as np
from PyQt5 import uic
import matplotlib.pyplot as plt


params = ['O1', 'O2', 'O3', 'O4', 'O5']
results = [4, 3.5, 4, 2, 3]

theta = np.linspace(start=0, stop=2*np.pi, num=len(results), endpoint=False)
theta = np.concatenate((theta, [theta[0]]))
results = np.append(results, results[0])
fig = plt.figure(figsize=(5, 5), facecolor='#f3f3f3')
ax = fig.add_subplot(111, projection='polar')
ax.plot(theta, results, linewidth=2, color="red")
ax.set_thetagrids(range(0, 360, int(360 / len(params))), (params))
plt.yticks(np.arange(0, 10, 1.0), fontsize=8)
ax.set(facecolor='#f3f3f3')
ax.set_theta_offset(np.pi / 2)

pl = ax.yaxis.get_gridlines()
for line in pl:
    line.get_path()._interpolation_steps = 5

plt.show()

Answer 1

Воспользовался ссылкой, которую вы указали и вот:

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=0.5, 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 = [['O1', 'O2', 'O3', 'O4', 'O5'],
        ('Title', [
                    [4, 3.5, 4, 2, 3,], 
                    [1.07, 5.95, 2.04, 1.05, 0.00,], 
                  ]
        )]

N = len(data[0])
theta = radar_factory(N, frame='polygon')                                     # polygon  !!!

spoke_labels = data.pop(0)
title, case_data = data[0]
fig, ax = plt.subplots(figsize=(5, 5), subplot_kw=dict(projection='radar'))
fig.subplots_adjust(top=0.85, bottom=0.05)
ax.set_rgrids([0, 1, 2.0, 3.0, 4.0, 5.0, 6])
ax.set_title(title,  position=(0.5, 1.1), ha='center')

for d in case_data:
    line = ax.plot(theta, d)
    ax.fill(theta, d,  alpha=0.25)
ax.set_varlabels(spoke_labels)

plt.show()

БЛОГ НА HUSL

Как построить лепестковую диаграмму на python c пятиугольной сеткой?

Ответы (1 шт):