Merge pull request #56 from PaulaGarciaMolina/main

Update algorithms tests

tests/test_arnoldi.py

@@ -1,7 +1,9 @@
 import numpy as np
-from seemps.optimization.arnoldi import arnoldi_eigh
-from seemps.hamiltonians import HeisenbergHamiltonian
+
 from seemps import MPO, product_state
+from seemps.hamiltonians import HeisenbergHamiltonian
+from seemps.optimization.arnoldi import arnoldi_eigh
+
 from .tools import *
 
 
@@ -26,15 +28,3 @@ def test_arnoldi_eigh_with_local_field(self):
         result = arnoldi_eigh(H, guess, maxiter=20, tol=1e-15)
         self.assertAlmostEqual(result.energy, H.expectation(exact))
         self.assertSimilarStates(result.state, exact, atol=1e-7)
-
-    def test_arnoldi_eigsh_acknowledges_tolerance(self):
-        """Check that algorithm stops if energy change is below tolerance."""
-        N = 4
-        H = HeisenbergHamiltonian(N).to_mpo()
-        tol = 1e-5
-        guess = CanonicalMPS(
-            random_uniform_mps(2, N, rng=self.rng), center=0, normalize=True
-        )
-        result = arnoldi_eigh(H, guess, tol=tol, maxiter=10)
-        self.assertTrue(result.converged)
-        self.assertTrue(abs(result.trajectory[-1] - result.trajectory[-2]) < tol)

tests/test_gradient_descent.py

@@ -1,7 +1,9 @@
 import numpy as np
-from seemps.optimization.descent import gradient_descent
-from seemps.hamiltonians import HeisenbergHamiltonian
+
 from seemps import MPO, product_state
+from seemps.hamiltonians import HeisenbergHamiltonian
+from seemps.optimization.descent import gradient_descent
+
 from .tools import *
 
 
@@ -59,4 +61,4 @@ def test_gradient_descent_with_callback(self):
             H, guess, maxiter=maxiter, tol=1e-15, callback=callback_func
         )
         self.assertSimilar(norms, np.ones(len(norms)))
-        self.assertEqual(maxiter, len(norms))
+        self.assertEqual(maxiter + 1, len(norms))

tests/test_itime.py

@@ -49,7 +49,7 @@ def test_euler_with_callback(self):
         callback_func, norms = callback()
         result = euler(H, guess, maxiter=maxiter, callback=callback_func)
         self.assertSimilar(norms, np.ones(len(norms)))
-        self.assertEqual(maxiter, len(norms))
+        self.assertEqual(maxiter + 1, len(norms))
 
 
 class TestImprovedEuler(TestCase):
@@ -82,7 +82,7 @@ def test_improved_euler_with_callback(self):
         callback_func, norms = callback()
         result = improved_euler(H, guess, maxiter=maxiter, callback=callback_func)
         self.assertSimilar(norms, np.ones(len(norms)))
-        self.assertEqual(maxiter, len(norms))
+        self.assertEqual(maxiter + 1, len(norms))
 
 
 class TestRungeKutta(TestCase):
@@ -115,7 +115,7 @@ def test_runge_kutta_with_callback(self):
         callback_func, norms = callback()
         result = runge_kutta(H, guess, maxiter=maxiter, callback=callback_func)
         self.assertSimilar(norms, np.ones(len(norms)))
-        self.assertEqual(maxiter, len(norms))
+        self.assertEqual(maxiter + 1, len(norms))
 
 
 class TestRungeKuttaFehlberg(TestCase):