WUT_Computer_Science/code/tests.py

80 lines
3.2 KiB
Python

import pytest
import numpy as np
from scipy.sparse.linalg import cg
from matrix_generator import MatrixGenerator
from richardson_method import RichardsonMethod
def calculate_norm_numpy(I, w, A):
# Calculate the difference between I and w * A
difference = I - w * A
# Calculate the Euclidean norm of the difference
norm = np.linalg.norm(difference)
return norm
def calculate_eigenvalues(A):
# Calculate the eigenvalues of matrix A
eigenvalues = np.linalg.eigvals(A)
# Find the minimum and maximum eigenvalues
lambda_min = np.min(eigenvalues)
lambda_max = np.max(eigenvalues)
return lambda_min, lambda_max
def calcualte_norm_from_matrix_numpy(A, n, max_iterations):
lambda_min, lambda_max = calculate_eigenvalues(A)
omega = 2 / (lambda_min + lambda_max)
I = np.eye(n)
return calculate_norm_numpy(I, omega, A)
@pytest.mark.parametrize("n", [2, 3, 4, 5, 10, 20, 50, 100])
def test_richardson_vs_cg(n: int):
print("matrix size: ", n)
tolerance = 1e-5
max_iterations=1000
A, b = MatrixGenerator.generate_random_matrix_and_vector(n)
richardson_solver = RichardsonMethod(A, b, max_iterations, size=n, tol=1e-7)
solution_richardson, info_richardson = richardson_solver.solve()
solution_cg, info = cg(A, b)
if info == 0: # SciPy CG converged
assert_scipy_converged(solution_richardson, info_richardson, solution_cg, tolerance, A, b, max_iterations, n)
else: # SciPy CG did not converge
assert_scipy_not_converged(solution_richardson, info_richardson, A, b)
def assert_scipy_converged(solution_richardson, info_richardson, solution_cg, tolerance, A, b, max_iterations, n):
if info_richardson == "Richardson method for those values will NOT converge":
print("Richardson did not converge, while SciPy did")
numpy_norm = calcualte_norm_from_matrix_numpy(A, n, max_iterations)
print("Numpy norm: ", numpy_norm, " Richardson norm: ", solution_richardson)
assert False, "Richardson did not converge, while SciPy did"
else:
difference = np.linalg.norm(solution_richardson - solution_cg)
print(f"Difference between Richardson and CG solutions: {difference:.8f}")
if difference < tolerance:
print("Both Richardson and CG converged and calculated correct values.")
print("Solution CG:\n", solution_cg)
print("Solution Richardson:\n", solution_richardson)
else:
print("Matrix A:\n", A)
print("Vector b:\n", b)
assert difference < tolerance, f"The solutions are different! Difference: {difference:.8f}"
def assert_scipy_not_converged(solution_richardson, info_richardson, A, b):
if info_richardson == "Richardson method for those values will NOT converge":
print("Richardson and SciPy did not converge")
else:
print("Richardson converged while SciPy did not:", solution_richardson)
print("Matrix A:\n", A)
print("Vector b:\n", b)
assert False, "Richardson converged while SciPy did not"
if __name__ == "__main__":
# Run pytest and exit with the appropriate status code
for n in [2, 3, 4, 5, 10, 20, 50, 100]:
test_richardson_vs_cg(n)