diff --git a/linear_algebra/src/rayleigh_quotient.py b/linear_algebra/src/rayleigh_quotient.py index d0d5d6396..69bbbac11 100644 --- a/linear_algebra/src/rayleigh_quotient.py +++ b/linear_algebra/src/rayleigh_quotient.py @@ -4,56 +4,55 @@ https://en.wikipedia.org/wiki/Rayleigh_quotient import numpy as np -def is_hermitian(matrix: np.matrix) -> bool: +def is_hermitian(matrix: np.array) -> bool: """ Checks if a matrix is Hermitian. - >>> import numpy as np - >>> A = np.matrix([ + >>> A = np.array([ ... [2, 2+1j, 4], ... [2-1j, 3, 1j], ... [4, -1j, 1]]) >>> is_hermitian(A) True - >>> A = np.matrix([ + >>> A = np.array([ ... [2, 2+1j, 4+1j], ... [2-1j, 3, 1j], ... [4, -1j, 1]]) >>> is_hermitian(A) False """ - return np.array_equal(matrix, matrix.H) + return np.array_equal(matrix, matrix.conjugate().T) -def rayleigh_quotient(A: np.matrix, v: np.matrix) -> float: +def rayleigh_quotient(A: np.array, v: np.array) -> float: """ Returns the Rayleigh quotient of a Hermitian matrix A and vector v. >>> import numpy as np - >>> A = np.matrix([ + >>> A = np.array([ ... [1, 2, 4], ... [2, 3, -1], ... [4, -1, 1] ... ]) - >>> v = np.matrix([ + >>> v = np.array([ ... [1], ... [2], ... [3] ... ]) >>> rayleigh_quotient(A, v) - matrix([[3.]]) + array([[3.]]) """ - v_star = v.H - return (v_star * A * v) / (v_star * v) + v_star = v.conjugate().T + return (v_star.dot(A).dot(v)) / (v_star.dot(v)) def tests() -> None: - A = np.matrix([[2, 2 + 1j, 4], [2 - 1j, 3, 1j], [4, -1j, 1]]) - v = np.matrix([[1], [2], [3]]) + A = np.array([[2, 2 + 1j, 4], [2 - 1j, 3, 1j], [4, -1j, 1]]) + v = np.array([[1], [2], [3]]) assert is_hermitian(A), f"{A} is not hermitian." print(rayleigh_quotient(A, v)) - A = np.matrix([[1, 2, 4], [2, 3, -1], [4, -1, 1]]) + A = np.array([[1, 2, 4], [2, 3, -1], [4, -1, 1]]) assert is_hermitian(A), f"{A} is not hermitian." assert rayleigh_quotient(A, v) == float(3)