def test_QRsolve():
A = Matrix([[2, 3, 5], [3, 6, 2], [8, 3, 6]])
x = Matrix(3, 1, [3, 7, 5])
b = A * x
soln = A.QRsolve(b)
assert soln == x
x = Matrix([[1, 2], [3, 4], [5, 6]])
b = A * x
soln = A.QRsolve(b)
assert soln == x
A = Matrix([[0, -1, 2], [5, 10, 7], [8, 3, 4]])
x = Matrix(3, 1, [-1, 2, 5])
b = A * x
soln = A.QRsolve(b)
assert soln == x
x = Matrix([[7, 8], [9, 10], [11, 12]])
b = A * x
soln = A.QRsolve(b)
assert soln == x
