2021-12-04 18:37:47 +08:00
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mindspore.nn.F1
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2021-12-04 13:55:42 +08:00
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=====================
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.. py:class:: mindspore.nn.F1
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计算F1 score。F1是Fbeta的特殊情况，即beta为1。
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有关更多详细信息，请参阅类:class:`mindspore.nn.Fbeta`。
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.. math::
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F_1=\frac{2\cdot true\_positive}{2\cdot true\_positive + false\_negative + false\_positive}
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**样例：**
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>>> import numpy as np
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>>> from mindspore import nn, Tensor
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>>>
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>>> x = Tensor(np.array([[0.2, 0.5], [0.3, 0.1], [0.9, 0.6]]))
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>>> y = Tensor(np.array([1, 0, 1]))
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>>> metric = nn.F1()
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>>> metric.update(x, y)
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>>> result = metric.eval()
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>>> print(result)
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[0.66666667 0.66666667]
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