[ENH]: Multi hatching in ax.stackplot() #27146
Description
Problem
ax.stackplot() is used for conveniently plotting stacked area plot.
The documentation says that any **kwargs is passed on to ax.fill_between.
So, it all works fine if I work with colours, but not so much with hatching pattern.
If I want to add hatching, this is what I get by default:
import matplotlib.pyplot as plt
import numpy as np
# Data
cols = 10
rows = 4
data = (
np.reshape(np.arange(0, cols, 1), (1, -1)) ** 2
+ np.reshape(np.arange(0, rows), (-1, 1))
+ np.random.random((rows, cols))*5
)
# Plot
fig, ax = plt.subplots(
figsize=(10,6),
facecolor="white",
layout="constrained"
)
fig.suptitle(
"with hatching",
fontsize=25,
weight="bold"
)
x = range(data.shape[1])
ax.stackplot(
x, data,
hatch="x"
)
ax.set_xlim(0, 9)
ax.set_ylim(0, 350)The outcome:
But I would be more interested in getting something like this:
Proposed solution
The calling signature would be the same as before with exception that the hatch parameter would accept e.g. a list with hatching styles you want to use.
Example:
ax.stackplot(
x, data,
hatch=["x", "\\", ".", "-"]
)The example I've used above in the problem was create using the code below and in this case it varies the hatching by the density:
fig, ax = plt.subplots(
figsize=(10,6),
facecolor="white",
layout="constrained"
)
fig.suptitle(
"with individual hatching",
fontsize=25,
weight="bold"
)
x = range(data.shape[1])
stack_baseline = np.zeros((data.shape[1]))
for i, y in enumerate(data):
ax.fill_between(
x, stack_baseline, y+stack_baseline,
facecolor=(1, 1, 1, 0),
hatch="x"*(data.shape[0]-i)
)
stack_baseline += y
ax.set_xlim(0, 9)
ax.set_ylim(0, 350)