sklearn.metrics.plot_confusion_matrix

sklearn.metrics.plot_confusion_matrix(estimator, X, y_true, *, labels=None, sample_weight=None, normalize=None, display_labels=None, include_values=True, xticks_rotation='horizontal', values_format=None, cmap='viridis', ax=None, colorbar=True)

DEPRECATED: Function plot_confusion_matrix is deprecated in 1.0 and will be removed in 1.2. Use one of the class methods: ConfusionMatrixDisplay.from_predictions or ConfusionMatrixDisplay.from_estimator.

Plot Confusion Matrix.

plot_confusion_matrix is deprecated in 1.0 and will be removed in 1.2. Use one of the following class methods: from_predictions or from_estimator.

Read more in the User Guide.

Parameters:

estimatorestimator instance

Fitted classifier or a fitted Pipeline in which the last estimator is a classifier.

X{array-like, sparse matrix} of shape (n_samples, n_features)

Input values.

y_truearray-like of shape (n_samples,)

Target values.

labelsarray-like of shape (n_classes,), default=None

List of labels to index the matrix. This may be used to reorder or select a subset of labels. If None is given, those that appear at least once in y_true or y_pred are used in sorted order.

sample_weightarray-like of shape (n_samples,), default=None

Sample weights.

normalize{‘true’, ‘pred’, ‘all’}, default=None

Either to normalize the counts display in the matrix:

• if 'true', the confusion matrix is normalized over the true conditions (e.g. rows);

• if 'pred', the confusion matrix is normalized over the predicted conditions (e.g. columns);

• if 'all', the confusion matrix is normalized by the total number of samples;

• if None (default), the confusion matrix will not be normalized.

display_labelsarray-like of shape (n_classes,), default=None

Target names used for plotting. By default, labels will be used if it is defined, otherwise the unique labels of y_true and y_pred will be used.

include_valuesbool, default=True

Includes values in confusion matrix.

xticks_rotation{‘vertical’, ‘horizontal’} or float, default=’horizontal’

Rotation of xtick labels.

values_formatstr, default=None

Format specification for values in confusion matrix. If None, the format specification is ‘d’ or ‘.2g’ whichever is shorter.

cmapstr or matplotlib Colormap, default=’viridis’

Colormap recognized by matplotlib.

axmatplotlib Axes, default=None

Axes object to plot on. If None, a new figure and axes is created.

colorbarbool, default=True

Whether or not to add a colorbar to the plot.

New in version 0.24.

Returns:

displayConfusionMatrixDisplay

Object that stores computed values.

See also

confusion_matrix

Compute Confusion Matrix to evaluate the accuracy of a classification.

ConfusionMatrixDisplay

Confusion Matrix visualization.

Examples

>>> import matplotlib.pyplot as plt
>>> from sklearn.datasets import make_classification
>>> from sklearn.metrics import plot_confusion_matrix
>>> from sklearn.model_selection import train_test_split
>>> from sklearn.svm import SVC
>>> X, y = make_classification(random_state=0)
>>> X_train, X_test, y_train, y_test = train_test_split(
...         X, y, random_state=0)
>>> clf = SVC(random_state=0)
>>> clf.fit(X_train, y_train)
SVC(random_state=0)
>>> plot_confusion_matrix(clf, X_test, y_test)  
>>> plt.show()