toqito.matrix_props.is_positive_definite ======================================== .. py:module:: toqito.matrix_props.is_positive_definite .. autoapi-nested-parse:: Checks if the matrix is a positive definite matrix. Module Contents --------------- .. py:function:: is_positive_definite(mat) Check if matrix is positive definite (PD) [@WikiPosDef]. .. rubric:: Examples Consider the following matrix \[ A = \begin{pmatrix} 2 & -1 & 0 \\ -1 & 2 & -1 \\ 0 & -1 & 2 \end{pmatrix} \] our function indicates that this is indeed a positive definite matrix. ```python exec="1" source="above" import numpy as np from toqito.matrix_props import is_positive_definite A = np.array([[2, -1, 0], [-1, 2, -1], [0, -1, 2]]) print(is_positive_definite(A)) ``` Alternatively, the following example matrix \(B\) defined as \[ B = \begin{pmatrix} -1 & -1 \\ -1 & -1 \end{pmatrix} \] is not positive definite. ```python exec="1" source="above" import numpy as np from toqito.matrix_props import is_positive_definite B = np.array([[-1, -1], [-1, -1]]) print(is_positive_definite(B)) ``` !!! See Also [`is_positive_semidefinite`][toqito.matrix_props.is_positive_semidefinite.is_positive_semidefinite] :param mat: Matrix to check. :returns: Return `True` if matrix is positive definite, and `False` otherwise.