I want to plot a confusion matrix to visualize the classifer's performance, but it shows only the numbers of the labels, not the labels themselves:
from sklearn.metrics import confusion_matrix
import pylab as pl
y_test=['business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business', 'business']
pred=array(['health', 'business', 'business', 'business', 'business',
'business', 'health', 'health', 'business', 'business', 'business',
'business', 'business', 'business', 'business', 'business',
'health', 'health', 'business', 'health'],
dtype='|S8')
cm = confusion_matrix(y_test, pred)
pl.matshow(cm)
pl.title('Confusion matrix of the classifier')
pl.colorbar()
pl.show()
How can I add the labels (health, business..etc) to the confusion matrix?
UPDATE:
In scikit-learn 0.22, there's a new feature to plot the confusion matrix directly.
See the documentation: sklearn.metrics.plot_confusion_matrix
OLD ANSWER:
I think it's worth mentioning the use of seaborn.heatmap
here.
import seaborn as sns
import matplotlib.pyplot as plt
ax= plt.subplot()
sns.heatmap(cm, annot=True, ax = ax); #annot=True to annotate cells
# labels, title and ticks
ax.set_xlabel('Predicted labels');ax.set_ylabel('True labels');
ax.set_title('Confusion Matrix');
ax.xaxis.set_ticklabels(['business', 'health']); ax.yaxis.set_ticklabels(['health', 'business']);