Source code for catalyst.contrib.utils.visualization

import itertools

import matplotlib.pyplot as plt  # noqa: E402
import numpy as np

[docs]def plot_confusion_matrix( cm: np.ndarray, class_names=None, normalize=False, title="confusion matrix", fname=None, show=True, figsize=12, fontsize=32, colormap="Blues", ): """Render the confusion matrix and return matplotlib"s figure with it. Normalization can be applied by setting `normalize=True`. Args: cm: numpy confusion matrix class_names: class names normalize: boolean flag to normalize confusion matrix title: title fname: filename to save confusion matrix show: boolean flag for preview figsize: matplotlib figure size fontsize: matplotlib font size colormap: matplotlib color map Returns: matplotlib figure """ plt.ioff() cmap =[colormap] if class_names is None: class_names = [str(i) for i in range(len(np.diag(cm)))] if normalize: cm = cm.astype(np.float32) / cm.sum(axis=1)[:, np.newaxis] plt.rcParams.update({"font.size": int(fontsize / np.log2(len(class_names)))}) figure = plt.figure(figsize=(figsize, figsize)) plt.title(title) plt.imshow(cm, interpolation="nearest", cmap=cmap) plt.colorbar() tick_marks = np.arange(len(class_names)) plt.xticks(tick_marks, class_names, rotation=45, ha="right") plt.yticks(tick_marks, class_names) fmt = ".2f" if normalize else "d" thresh = cm.max() / 2.0 for i, j in itertools.product(range(cm.shape[0]), range(cm.shape[1])): plt.text( j, i, format(cm[i, j], fmt), horizontalalignment="center", color="white" if cm[i, j] > thresh else "black", ) plt.tight_layout() plt.ylabel("True label") plt.xlabel("Predicted label") if fname is not None: plt.savefig(fname=fname) if show: plt.ion() return figure
[docs]def render_figure_to_array(figure): """Renders matplotlib"s figure to tensor.""" plt.ioff() figure.canvas.draw() image = np.array(figure.canvas.renderer._renderer) plt.close(figure) del figure plt.ion() return image
__all__ = [ "plot_confusion_matrix", "render_figure_to_array", ]