223031012
/
DAMASK_EICMD
mirror of https://github.com/achalhp/DAMASK_EICMD.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

use scipy.linalg.polar 

unfortunately, it does not support arbitrary dimensions, so use it as
reference in testing only
This commit is contained in:
Martin Diehl 2024-02-06 22:27:52 +01:00 committed by achalhp
parent dccecf6753
commit 28a83d6b69
1 changed files with 12 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
python/tests/test_mechanics.py
View File

@ -1,5 +1,6 @@
import pytest import pytest
import numpy as np import numpy as np
from scipy import linalg
from damask import tensor from damask import tensor
from damask import mechanics from damask import mechanics
@ -145,7 +146,7 @@ class TestMechanics:
P = np.random.rand(self.n,3,3) P = np.random.rand(self.n,3,3)
assert np.allclose(function(P,np.broadcast_to(np.eye(3),(self.n,3,3))),tensor.symmetric(P)) assert np.allclose(function(P,np.broadcast_to(np.eye(3),(self.n,3,3))),tensor.symmetric(P))
def test_polar_decomposition(self): def test_polar_decomposition_identity(self):
"""F = RU = VR.""" """F = RU = VR."""
F = np.broadcast_to(np.eye(3),[self.n,3,3])*np.random.rand(self.n,3,3) F = np.broadcast_to(np.eye(3),[self.n,3,3])*np.random.rand(self.n,3,3)
R = mechanics.rotation(F).as_matrix() R = mechanics.rotation(F).as_matrix()
@ -154,6 +155,16 @@ class TestMechanics:
assert np.allclose(np.matmul(R,U), assert np.allclose(np.matmul(R,U),
np.matmul(V,R)) np.matmul(V,R))
@pytest.mark.parametrize('side',[('left','V'),('right','U')])
def test_polar_decomposition(self,side):
F = np.random.rand(self.n,3,3)
F = np.einsum('...ij,...jk',F,F) # positive determinant
F_vec = np.reshape(F,(self.n//10,10,3,3))
p = mechanics._polar_decomposition(F_vec,side[1])
for p_,F_ in zip(np.reshape(p,F.shape),F):
if np.linalg.det(F_) < 1.e-7: continue
assert np.allclose(p_,linalg.polar(F_,side[0])[1])
@pytest.mark.parametrize('m',[0.0,np.random.random()*10.,np.random.random()*-10.]) @pytest.mark.parametrize('m',[0.0,np.random.random()*10.,np.random.random()*-10.])
def test_strain_no_rotation(self,m): def test_strain_no_rotation(self,m):
"""Ensure that left and right stretch give same results for no rotation.""" """Ensure that left and right stretch give same results for no rotation."""