ConfusionMatrixDisplay (Scikit-Learn) plot labels out of range

Question

The following code plots a confusion matrix:

from sklearn.metrics import ConfusionMatrixDisplay

confusion_matrix = confusion_matrix(y_true, y_pred)
target_names = ["aaaaa", "bbbbbb", "ccccccc", "dddddddd", "eeeeeeeeee", "ffffffff", "ggggggggg"]
disp = ConfusionMatrixDisplay(confusion_matrix=confusion_matrix, display_labels=target_names)
disp.plot(cmap=plt.cm.Blues, xticks_rotation=45)
plt.savefig("conf.png")

There are two problems with this plot.

The y-axis label is cut off (True Label). The x label is cut off too.
The names are to long for the x-axis.

To solve the first problem I tried to use poof(bbox_inches='tight') which is unfortunately not available for sklearn. In the second case I tried the following solution for 2. which lead to a completely distorted plot.

All in all I'm struggeling with both problems.

try rcParams like `import matplotlib.pyplot as plt plt.rcParams["figure.figsize"] = (15,10)`. so changing Width, height. — simpleApp, May 21 '21 at 12:51
is the line `plt.rcParams["figure.figsize"] = (15,10)` added before `disp.plot` ? or I mean need to be before the plot. — simpleApp, May 21 '21 at 13:00
This actually did the job done. Now there is a large blank area around the plot. Do I need to crop it manually? — Jürgen K., May 21 '21 at 13:03

score 6 · Accepted Answer · answered May 21 '21 at 13:02

I think the easiest way would be to switch into tight_layout and add pad_inches= something.

from sklearn.metrics import confusion_matrix
from sklearn.metrics import ConfusionMatrixDisplay
import matplotlib.pyplot as plt
from numpy.random import default_rng

rand = default_rng()
y_true = rand.integers(low=0, high=7, size=500)
y_pred = rand.integers(low=0, high=7, size=500)


confusion_matrix = confusion_matrix(y_true, y_pred)
target_names = ["aaaaa", "bbbbbb", "ccccccc", "dddddddd", "eeeeeeeeee", "ffffffff", "ggggggggg"]
disp = ConfusionMatrixDisplay(confusion_matrix=confusion_matrix, display_labels=target_names)
disp.plot(cmap=plt.cm.Blues, xticks_rotation=45)

plt.tight_layout()
plt.savefig("conf.png", pad_inches=5)

Result:

ConfusionMatrixDisplay (Scikit-Learn) plot labels out of range

1 Answers1