Exemple #1
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    def test_svd_thresh_coef(self):
        """Test svd_thresh_coef."""
        npt.assert_almost_equal(
            svd.svd_thresh_coef(self.data1, lambda x_val: x_val, 0),
            self.data1,
            err_msg='Incorrect SVD coefficient tresholding',
        )

        npt.assert_raises(TypeError, svd.svd_thresh_coef, self.data1, 0, 0)
Exemple #2
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    def _op_method(self, input_data, extra_factor=1.0, rank=None):
        """Operator.

        This method returns the input data after the singular values have been
        thresholded.

        Parameters
        ----------
        input_data : numpy.ndarray
            Input data array
        extra_factor : float
            Additional multiplication factor (default is ``1.0``)
        rank: int, optional
            Estimation of the rank to save computation time in standard mode,
            if not set an internal estimation is used.

        Returns
        -------
        numpy.ndarray
            SVD thresholded data

        Raises
        ------
        ValueError
            if lowr_type is not in ``{'standard', 'ngole'}``
        """
        # Update threshold with extra factor.
        threshold = self.thresh * extra_factor
        if self.lowr_type == 'standard' and self.rank is None and rank is None:
            data_matrix = svd_thresh(
                cube2matrix(input_data),
                threshold,
                thresh_type=self.thresh_type,
            )
        elif self.lowr_type == 'standard':
            data_matrix, update_rank = svd_thresh_coef_fast(
                cube2matrix(input_data),
                threshold,
                n_vals=rank or self.rank,
                extra_vals=5,
                thresh_type=self.thresh_type,
            )
            self.rank = update_rank  # save for future use

        elif self.lowr_type == 'ngole':
            data_matrix = svd_thresh_coef(
                cube2matrix(input_data),
                self.operator,
                threshold,
                thresh_type=self.thresh_type,
            )
        else:
            raise ValueError('lowr_type should be standard or ngole')

        # Return updated data.
        return matrix2cube(data_matrix, input_data.shape[1:])
Exemple #3
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    def _op_method(self, input_data, extra_factor=1.0):
        """Operator.

        This method returns the input data after the singular values have been
        thresholded.

        Parameters
        ----------
        input_data : numpy.ndarray
            Input data array
        extra_factor : float
            Additional multiplication factor (default is ``1.0``)

        Returns
        -------
        numpy.ndarray
            SVD thresholded data

        """
        # Update threshold with extra factor.
        threshold = self.thresh * extra_factor

        if self.lowr_type == 'standard':
            data_matrix = svd_thresh(
                cube2matrix(input_data),
                threshold,
                thresh_type=self.thresh_type,
            )

        elif self.lowr_type == 'ngole':
            data_matrix = svd_thresh_coef(
                cube2matrix(input_data),
                self.operator,
                threshold,
                thresh_type=self.thresh_type,
            )

        # Return updated data.
        return matrix2cube(data_matrix, input_data.shape[1:])