35 lines
709 B
Python
35 lines
709 B
Python
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import numpy as np
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from sklearn.utils import safe_asarray
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from sklearn.utils import deprecated
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def _balance_weights(y):
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"""Compute sample weights such that the class distribution of y becomes
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balanced.
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Parameters
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----------
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y : array-like
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Labels for the samples.
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Returns
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-------
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weights : array-like
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The sample weights.
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"""
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y = safe_asarray(y)
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y = np.searchsorted(np.unique(y), y)
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bins = np.bincount(y)
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weights = 1. / bins.take(y)
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weights *= bins.min()
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return weights
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@deprecated('balance_weights is an internal function and will be removed '
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'in 0.16')
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def balance_weights(y):
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return _balance_weights(y)
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