Example #1
0
    def test_ortho_PBC(self):
        from MDAnalysis.core.distances import applyPBC

        U = MDAnalysis.Universe(PSF, DCD)
        atoms = U.atoms.coordinates()
        box1 = np.array([2.5, 2.5, 3.5], dtype=np.float32)
        box2 = np.array([2.5, 2.5, 3.5, 90., 90., 90.], dtype=np.float32)

        cyth1 = applyPBC(atoms, box1)
        cyth2 = applyPBC(atoms, box2)
        reference = atoms - np.floor(atoms / box1) * box1

        assert_almost_equal(cyth1, reference, self.prec, err_msg="Ortho applyPBC #1 failed comparison with np")
        assert_almost_equal(cyth2, reference, self.prec, err_msg="Ortho applyPBC #2 failed comparison with np")
Example #2
0
    def test_tric_PBC(self):
        from MDAnalysis.core.distances import applyPBC

        U = MDAnalysis.Universe(TRIC)
        atoms = U.atoms.coordinates()
        box1 = U.dimensions
        box2 = MDAnalysis.coordinates.core.triclinic_vectors(box1)

        print box2
        print box2.shape

        def numpy_PBC(coords, box):
            coords -= np.array([box[2] * val for val in np.floor(coords[:, 2] / box[2][2])])
            coords -= np.array([box[1] * val for val in np.floor(coords[:, 1] / box[1][1])])
            coords -= np.array([box[0] * val for val in np.floor(coords[:, 0] / box[0][0])])

            return coords

        cyth1 = applyPBC(atoms, box1)
        cyth2 = applyPBC(atoms, box2)
        reference = numpy_PBC(atoms, box2)

        assert_almost_equal(cyth1, reference, self.prec, err_msg="Triclinic applyPBC failed comparison with np")
        assert_almost_equal(cyth2, reference, self.prec, err_msg="Trlclinic applyPBC failed comparison with np")