Is there a way to plot pie chart in matplotlib heatmap? - matplotlib

Question

I have a heatmap with several rows and columns.
Formerly, I was plotting a circle for each (row_index,column_index) and appending this circle to a circle_list. I was adding circle_list as a collection to the axes.
import matplotlib.pyplot as plt
import numpy as np
from matplotlib.collections import PatchCollection
def heatmap_with_circles(data_array,row_labels,column_labels,ax=None, cmap=None, norm=None, cbar_kw={}, cbarlabel="", **kwargs):
circles=[]
for row_index, row in enumerate(row_labels):
for column_index, column in enumerate(column_labels):
circles.append(plt.Circle((row_index,column_index),radius=0.4))
col = PatchCollection(circles, array=data_array.flatten(), cmap=cmap, norm=norm)
ax.add_collection(col)
# We want to show all ticks...
ax.set_xticks(np.arange(data_array.shape[1]))
ax.set_yticks(np.arange(data_array.shape[0]))
fontsize=10
ax.set_xticklabels(column_labels, fontsize=fontsize)
ax.set_yticklabels(row_labels, fontsize=fontsize)
#X axis labels at top
ax.tick_params(top=True, bottom=False,labeltop=True, labelbottom=False,pad=5)
plt.setp(ax.get_xticklabels(), rotation=55, ha="left", rotation_mode="anchor")
# We want to show all ticks...
ax.set_xticks(np.arange(data_array.shape[1]+1)-.5, minor=True)
ax.set_yticks(np.arange(data_array.shape[0]+1)-.5, minor=True)
ax.grid(which="minor", color="black", linestyle='-', linewidth=3)
ax.tick_params(which="minor", bottom=False, left=False)
data_array=np.random.rand(3,4)
row_labels=['Row1', 'Row2', 'Row3']
column_labels=['Column1', 'Column2', 'Column3','Column4']
fig, ax = plt.subplots(figsize=(1.9*len(row_labels),1.2*len(column_labels)))
ax.set_aspect(1.0)
ax.set_facecolor('white')
heatmap_with_circles(data_array,row_labels,column_labels, ax=ax)
plt.tight_layout()
plt.show()
However, now I need to plot a pie chart instead of a circle.
And pie chart does not have (row_index,column_index) parameters.
Is there a way to plot pie chart in each cell of matplotlib heatmap?
Updating the for loop in heatmap_with_circles as follows:
for row_index, row in enumerate(row_labels,0):
for column_index, column in enumerate(column_labels,0):
wedges, _ = plt.pie([20, 10, 5])
radius = 0.45
[w.set_center((column_index,row_index)) for w in wedges]
[w.set_radius(radius) for w in wedges]
results in

Answer 1

You can access each wedge created by plt.pie individually and then use set_radius and set_position to rescale the different wedges.
wedges, _ = plt.pie([1,2,3])
x_position, y_position = 0, 0
radius = 0.2
[w.set_center((x_position,y_position)) for w in wedges]
[w.set_radius(radius) for w in wedges]
Edit:
On your code, in the for loop
for row_index, row in enumerate(row_labels):
for column_index, column in enumerate(column_labels):
wedges, _ = plt.pie([1,2,3])
[w.set_center((row_index,column_index)) for w in wedges]
[w.set_radius(0.4) for w in wedges]