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

vectorized conversion from ax(is angle)

This commit is contained in:
Martin Diehl 2020-04-08 20:50:42 +02:00
parent 62ddfe098c
commit 464620b796
2 changed files with 75 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
python/damask/_rotation.py
View File

@ -653,6 +653,7 @@ class Rotation:
@staticmethod
def ax2qu(ax):
"""Axis angle pair to quaternion."""
if len(ax.shape) == 1:
if np.abs(ax[3])<1.e-6:
qu = np.array([ 1.0, 0.0, 0.0, 0.0 ])
else:
@ -660,10 +661,18 @@ class Rotation:
s = np.sin(ax[3]*0.5)
qu = np.array([ c, ax[0]*s, ax[1]*s, ax[2]*s ])
return qu
else:
c = np.cos(ax[...,3:4]*.5)
s = np.sin(ax[...,3:4]*.5)
qu = np.where(np.abs(ax[...,3:4])<1.e-12,
[1.0, 0.0, 0.0, 0.0],
np.block([c, ax[...,:3]*s]))
return qu
@staticmethod
def ax2om(ax):
"""Axis angle pair to rotation matrix."""
if len(ax.shape) == 1:
c = np.cos(ax[3])
s = np.sin(ax[3])
omc = 1.0-c
@ -674,6 +683,20 @@ class Rotation:
om[idx[0],idx[1]] = q + s*ax[idx[2]]
om[idx[1],idx[0]] = q - s*ax[idx[2]]
return om if P < 0.0 else om.T
else:
c = np.cos(ax[...,3:4])
s = np.sin(ax[...,3:4])
omc = 1. -c
ax = np.block([c+omc*ax[...,0:1]**2,
omc*ax[...,0:1]*ax[...,1:2] + s*ax[...,2:3],
omc*ax[...,0:1]*ax[...,2:3] - s*ax[...,1:2],
omc*ax[...,0:1]*ax[...,1:2] - s*ax[...,2:3],
c+omc*ax[...,1:2]**2,
omc*ax[...,1:2]*ax[...,2:3] + s*ax[...,0:1],
omc*ax[...,0:1]*ax[...,2:3] + s*ax[...,1:2],
omc*ax[...,1:2]*ax[...,2:3] - s*ax[...,0:1],
c+omc*ax[...,2:3]**2]).reshape(ax.shape[:-1]+(3,3))
return ax
@staticmethod
def ax2eu(ax):
@ -683,6 +706,7 @@ class Rotation:
@staticmethod
def ax2ro(ax):
"""Axis angle pair to Rodrigues-Frank vector."""
if len(ax.shape) == 1:
if np.abs(ax[3])<1.e-6:
ro = [ 0.0, 0.0, P, 0.0 ]
else:
@ -691,13 +715,26 @@ class Rotation:
ro += [np.inf] if np.isclose(ax[3],np.pi,atol=1.0e-15,rtol=0.0) else \
[np.tan(ax[3]*0.5)]
return np.array(ro)
else:
ro = np.block([ax[...,:3],
np.where(np.isclose(ax[...,3:4],np.pi,atol=1.e-15,rtol=.0),
np.inf,
np.tan(ax[...,3:4]*0.5))
])
ro[np.abs(ax[...,3])<1.e-6] = [.0,.0,P,.0]
return ro
@staticmethod
def ax2ho(ax):
"""Axis angle pair to homochoric vector."""
if len(ax.shape) == 1:
f = (0.75 * ( ax[3] - np.sin(ax[3]) ))**(1.0/3.0)
ho = ax[0:3] * f
return ho
else:
f = (0.75 * ( ax[...,3:4] - np.sin(ax[...,3:4]) ))**(1.0/3.0)
ho = ax[...,:3] * f
return ho
@staticmethod
def ax2cu(ax):

14
python/tests/test_Rotation.py
View File

@ -78,7 +78,7 @@ def default():
specials /= np.linalg.norm(specials,axis=1).reshape(-1,1)
specials[specials[:,0]<0]*=-1
return [Rotation.fromQuaternion(s) for s in specials] + \
[Rotation.fromRandom() for r in range(n-len(specials))]
[Rotation.fromRandom() for _ in range(n-len(specials))]
@pytest.fixture
def reference_dir(reference_dir_base):
@ -149,3 +149,15 @@ class TestRotation:
o = Rotation.fromQuaternion(rot.asQuaternion()).asCubochoric()
print(m,o,rot.asQuaternion())
assert np.allclose(m,o,atol=atol)
@pytest.mark.parametrize('conversion',[Rotation.ax2qu,
Rotation.ax2om,
Rotation.ax2ro,
Rotation.ax2ho,
])
def test_axisAngle_vectorization(self,default,conversion):
ax = np.array([rot.asAxisAngle() for rot in default])
dev_null = conversion(ax.reshape(ax.shape[0]//2,-1,4))
co = conversion(ax)
for a,c in zip(ax,co):
assert np.allclose(conversion(a),c)