mindspore.nn.auc

mindspore.nn.auc(x, y, reorder=False)[source]

Computes the Area Under the Curve (AUC) using the trapezoidal rule. This is a general function, given points on a curve. For computing the area under the ROC-curve.

Parameters

x (Union[np.array, list]) – From the ROC curve(fpr), np.array with false positive rates. If multiclass, this is a list of such np.array, one for each class. The shape \((N)\).
y (Union[np.array, list]) – From the ROC curve(tpr), np.array with true positive rates. If multiclass, this is a list of such np.array, one for each class. The shape \((N)\).
reorder (boolean) – If True, assume that the curve is ascending in the case of ties, as for an ROC curve. If the curve is non-ascending, the result will be wrong. Default: False.

Returns

Compute result.

Return type

area (float)

Supported Platforms:: Ascend GPU CPU

Examples

>>> import numpy as np
>>> from mindspore import nn
>>>
>>> y_pred = np.array([[3, 0, 1], [1, 3, 0], [1, 0, 2]])
>>> y = np.array([[0, 2, 1], [1, 2, 1], [0, 0, 1]])
>>> metric = nn.ROC(pos_label=2)
>>> metric.clear()
>>> metric.update(y_pred, y)
>>> fpr, tpr, thre = metric.eval()
>>> output = auc(fpr, tpr)
>>> print(output)
0.5357142857142857