Source code for mindspore.nn.metrics.cosine_similarity

# Copyright 2021 Huawei Technologies Co., Ltd
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"""CosineSimilarity."""
from __future__ import absolute_import

import numpy as np

from mindspore._checkparam import Validator as validator
from mindspore.nn.metrics.metric import Metric, rearrange_inputs


[文档]class CosineSimilarity(Metric): """ Computes representation similarity. Args: similarity (str): 'dot' or 'cosine'. Default: 'cosine'. reduction (str): 'none', 'sum', 'mean' (all along dim -1). Default: 'none'. zero_diagonal (bool): If True, diagonals of results will be set to zero. Default: True. Supported Platforms: ``Ascend`` ``GPU`` ``CPU`` Examples: >>> import numpy as np >>> from mindspore import nn >>> >>> test_data = np.array([[1, 3, 4, 7], [2, 4, 2, 5], [3, 1, 5, 8]]) >>> metric = nn.CosineSimilarity() >>> metric.clear() >>> metric.update(test_data) >>> square_matrix = metric.eval() >>> print(square_matrix) [[0. 0.94025615 0.95162452] [0.94025615 0. 0.86146098] [0.95162452 0.86146098 0.]] """ def __init__(self, similarity='cosine', reduction='none', zero_diagonal=True): super().__init__() similarity_list = ['dot', 'cosine'] reduction_list = ['none', 'sum', 'mean'] similarity = validator.check_value_type("similarity", similarity, [str]) self.similarity = validator.check_string(similarity, similarity_list, "similarity") reduction = validator.check_value_type("reduction", reduction, [str]) self.reduction = validator.check_string(reduction, reduction_list, "reduction") self.zero_diagonal = validator.check_value_type("zero_diagonal", zero_diagonal, [bool]) self.sqr_mtx_res = 0 self.clear() self._is_update = None
[文档] def clear(self): """Clears the internal evaluation result.""" self.sqr_mtx_res = 0 self._is_update = False
[文档] @rearrange_inputs def update(self, inputs): """ Updates the internal evaluation result with 'inputs'. Args: inputs (Union[Tensor, list, numpy.ndarray]): The input matrix. """ input_data = self._convert_data(inputs) if self.similarity == 'cosine': data = np.linalg.norm(input_data, ord=2, axis=1) input_data = input_data / np.expand_dims(data, 1) self.sqr_mtx_res = np.dot(input_data, input_data.transpose(1, 0)) self._is_update = True
[文档] def eval(self): """ Computes the similarity matrix. Returns: numpy.ndarray. The similarity matrix. Raises: RuntimeError: If the update method is not called first, an error will be reported. """ if not self._is_update: raise RuntimeError("Please call the 'update' method before calling 'eval' method.") if self.zero_diagonal: np.fill_diagonal(self.sqr_mtx_res, 0) if self.reduction == 'mean': self.sqr_mtx_res = np.mean(self.sqr_mtx_res, axis=-1) if self.reduction == 'sum': self.sqr_mtx_res = np.sum(self.sqr_mtx_res, axis=-1) return self.sqr_mtx_res