4f3da275037d4fe3108039fdbfc03b2f81fbee8c,dipy/reconst/dti.py,,ols_fit_tensor,#Any#Any#,1251

Before Change

    data = np.asarray(data)
    data_flat = data.reshape((-1, data.shape[-1]))
    evals = np.empty((len(data_flat), 3))
    evecs = np.empty((len(data_flat), 3, 3))
    dti_params = np.empty((len(data_flat), 4, 3))

    //obtain OLS fitting matrix

After Change

    //math: ols_fit = X*beta_ols*inv(y)
    //ols_fit =  np.dot(U, U.T)

    evals, evecs = decompose_tensor(
        from_lower_triangular(
            np.einsum("...ij,...j",
                      np.linalg.pinv(design_matrix),
                      np.log(np.asarray(data)))
        ),
        min_diffusivity=tol / -design_matrix.min()
    )

    dti_params = np.concatenate((evals[..., None, :], evecs), axis=-2)
    return dti_params.reshape(data.shape[:-1] + (12,))

Instances