import eigenpy import numpy as np dim = 100 A = np.eye(dim) minres = eigenpy.MINRES(A) X = np.random.rand(dim, 20) B = A.dot(X) X_est = minres.solve(B) print("A.dot(X_est):", A.dot(X_est)) print("B:", B) assert eigenpy.is_approx(A.dot(X_est), B, 1e-6)