Rotation class

uses (and hides) Quaternion2. Should replace Quaternion class.
Orientation class should inherit from Rotation and adds symmetry.
This commit is contained in:
Martin Diehl 2019-02-11 23:50:02 +01:00
parent e931b716fd
commit 7ee933b79d
2 changed files with 346 additions and 1 deletions

View File

@ -13,7 +13,7 @@ from .asciitable import ASCIItable # noqa
from .config import Material # noqa
from .colormaps import Colormap, Color # noqa
from .orientation import Quaternion, Symmetry, Orientation # noqa
from .orientation import Quaternion, Symmetry, Rotation, Orientation # noqa
#from .block import Block # only one class
from .result import Result # noqa

View File

@ -10,6 +10,350 @@ from . import Lambert
P = -1
####################################################################################################
class Quaternion2:
u"""
Quaternion with basic operations
q is the real part, p = (x, y, z) are the imaginary parts.
Defintion of multiplication depends on variable P, P {-1,1}.
"""
def __init__(self,
q = 0.0,
p = np.zeros(3,dtype=float)):
"""Initializes to identity unless specified"""
self.q = q
self.p = np.array(p)
def __copy__(self):
"""Copy"""
return self.__class__(q=self.q,
p=self.p.copy())
copy = __copy__
def __iter__(self):
"""Components"""
return iter(self.asList())
def asArray(self):
"""As numpy array"""
return np.array((self.q,self.p[0],self.p[1],self.p[2]))
def asList(self):
return [self.q]+list(self.p)
def __repr__(self):
"""Readable string"""
return 'Quaternion(real={q:+.6f}, imag=<{p[0]:+.6f}, {p[1]:+.6f}, {p[2]:+.6f}>)'.format(q=self.q,p=self.p)
def __add__(self, other):
"""Addition"""
if isinstance(other, Quaternion2):
return self.__class__(q=self.q + other.q,
p=self.p + other.p)
else:
return NotImplemented
def __iadd__(self, other):
"""In-place addition"""
if isinstance(other, Quaternion2):
self.q += other.q
self.p += other.p
return self
else:
return NotImplemented
def __pos__(self):
"""Unary positive operator"""
return self
def __sub__(self, other):
"""Subtraction"""
if isinstance(other, Quaternion2):
return self.__class__(q=self.q - other.q,
p=self.p - other.p)
else:
return NotImplemented
def __isub__(self, other):
"""In-place subtraction"""
if isinstance(other, Quaternion2):
self.q -= other.q
self.p -= other.p
return self
else:
return NotImplemented
def __neg__(self):
"""Unary positive operator"""
self.q *= -1.0
self.p *= -1.0
return self
def __mul__(self, other):
"""Multiplication with quaternion or scalar"""
if isinstance(other, Quaternion2):
return self.__class__(q=self.q*other.q - np.dot(self.p,other.p),
p=self.q*other.p + other.q*self.p + P * np.cross(self.p,other.p))
elif isinstance(other, (int, float)):
return self.__class__(q=self.q*other,
p=self.p*other)
else:
return NotImplemented
def __imul__(self, other):
"""In-place multiplication with quaternion or scalar"""
if isinstance(other, Quaternion2):
self.q = self.q*other.q - np.dot(self.p,other.p)
self.p = self.q*other.p + other.q*self.p + P * np.cross(self.p,other.p)
return self
elif isinstance(other, (int, float)):
self *= other
return self
else:
return NotImplemented
def __truediv__(self, other):
"""Divsion with quaternion or scalar"""
if isinstance(other, Quaternion2):
s = other.conjugate()/abs(other)**2.
return self.__class__(q=self.q * s,
p=self.p * s)
elif isinstance(other, (int, float)):
self.q /= other
self.p /= other
return self
else:
return NotImplemented
def __itruediv__(self, other):
"""In-place divsion with quaternion or scalar"""
if isinstance(other, Quaternion2):
s = other.conjugate()/abs(other)**2.
self *= s
return self
elif isinstance(other, (int, float)):
self.q /= other
return self
else:
return NotImplemented
def __pow__(self, exponent):
"""Power"""
if isinstance(exponent, (int, float)):
omega = np.acos(self.q)
return self.__class__(q= np.cos(exponent*omega),
p=self.p * np.sin(exponent*omega)/np.sin(omega))
else:
return NotImplemented
def __ipow__(self, exponent):
"""In-place power"""
if isinstance(exponent, (int, float)):
omega = np.acos(self.q)
self.q = np.cos(exponent*omega)
self.p *= np.sin(exponent*omega)/np.sin(omega)
else:
return NotImplemented
def __abs__(self):
"""Norm"""
return math.sqrt(self.q ** 2 + np.dot(self.p,self.p))
magnitude = __abs__
def __eq__(self,other):
"""Equal (sufficiently close) to each other"""
return np.isclose(( self-other).magnitude(),0.0) \
or np.isclose((-self-other).magnitude(),0.0)
def __ne__(self,other):
"""Not equal (sufficiently close) to each other"""
return not self.__eq__(other)
def normalize(self):
d = self.magnitude()
if d > 0.0:
self.q /= d
self.p /= d
return self
def normalized(self):
return self.copy().normalize()
def conjugate(self):
self.p = -self.p
return self
def conjugated(self):
return self.copy().conjugate()
def homomorph(self):
if self.q < 0.0:
self.q = -self.q
self.p = -self.p
return self
def homomorphed(self):
return self.copy().homomorph()
####################################################################################################
class Rotation:
u"""
Orientation stored as unit quaternion.
All methods and naming conventions based on Rowenhorst_etal2015
Convention 1: coordinate frames are right-handed
Convention 2: a rotation angle ω is taken to be positive for a counterclockwise rotation
when viewing from the end point of the rotation axis towards the origin
Convention 3: rotations will be interpreted in the passive sense
Convention 4: Euler angle triplets are implemented using the Bunge convention,
with the angular ranges as [0, 2π],[0, π],[0, 2π]
Convention 5: the rotation angle ω is limited to the interval [0, π]
Convention 6: P = -1 (as default)
q is the real part, p = (x, y, z) are the imaginary parts.
Vector "a" (defined in coordinate system "A") is passively rotated
resulting in new coordinates "b" when expressed in system "B".
b = Q * a
b = np.dot(Q.asMatrix(),a)
ToDo: Denfine how to 3x3 and 3x3x3x3 matrices
"""
__slots__ = ['quaternion']
def __init__(self,quaternion = np.array([1.0,0.0,0.0,0.0])):
"""Initializes to identity unless specified"""
self.quaternion = Quaternion2(q=quaternion[0],p=quaternion[1:4])
self.quaternion.homomorph() # ToDo: Needed?
def __repr__(self):
"""Value in selected representation"""
return '\n'.join([
'Quaternion: {}'.format(self.quaternion),
'Matrix:\n{}'.format( '\n'.join(['\t'.join(list(map(str,self.asMatrix()[i,:]))) for i in range(3)]) ),
'Bunge Eulers / deg: {}'.format('\t'.join(list(map(str,self.asEulers(degrees=True)))) ),
])
def asQuaternion(self):
return self.quaternion.asArray()
def asEulers(self,
degrees = False):
return np.degrees(qu2eu(self.quaternion.asArray())) if degrees else qu2eu(self.quaternion.asArray())
def asAngleAxis(self,
degrees = False):
ax = qu2ax(self.quaternion.asArray())
if degrees: ax[0] = np.degrees(ax[0])
return ax
def asMatrix(self):
return qu2om(self.quaternion.asArray())
def asRodrigues(self):
return qu2ro(self.quaternion.asArray())
def asHomochoric(self):
return qu2ho(self.quaternion.asArray())
def asCubochoric(self):
return qu2cu(self.quaternion.asArray())
@classmethod
def fromQuaternion(cls,
quaternion,
P = -1):
qu = quaternion
if P > 0: qu[1:3] *= -1 # convert from P=1 to P=-1
if qu[0] < 0.0:
raise ValueError('Quaternion has negative first component.\n{}'.format(qu[0]))
if not np.isclose(np.linalg.norm(qu), 1.0):
raise ValueError('Quaternion is not of unit length.\n{} {} {} {}'.format(*qu))
return cls(qu)
@classmethod
def fromEulers(cls,
eulers,
degrees = False):
eu = np.radians(eulers) if degrees else eulers
if np.any(eu < 0.0) or np.any(eu > 2.0*np.pi) or eu[1] > np.pi:
raise ValueError('Euler angles outside of [0..2π],[0..π],[0..2π].\n{} {} {}.'.format(*eu))
return cls(eu2qu(eu))
@classmethod
def fromAngleAxis(cls,
angleAxis,
degrees = False,
P = -1):
ax = angleAxis
if P > 0: ax[1:3] *= -1 # convert from P=1 to P=-1
if degrees: ax[0] = np.degrees(ax[0])
if ax[0] < 0.0 or ax[0] > np.pi:
raise ValueError('Axis angle rotation angle outside of [0..π].\n'.format(ax[0]))
if not np.isclose(np.linalg.norm(ax[1:3]), 1.0):
raise ValueError('Axis angle rotation axis is not of unit length.\n{} {} {}'.format(*ax[1:3]))
return cls(ax2qu(ax))
@classmethod
def fromMatrix(cls,
matrix):
om = matrix
if not np.isclose(np.linalg.det(om),1.0):
raise ValueError('matrix is not a proper rotation.\n{}'.format(om))
if not np.isclose(np.dot(om[0],om[1]), 0.0) \
or not np.isclose(np.dot(om[1],om[2]), 0.0) \
or not np.isclose(np.dot(om[2],om[0]), 0.0):
raise ValueError('matrix is not orthogonal.\n{}'.format(om))
return cls(om2qu(om))
@classmethod
def fromRodrigues(cls,
rodrigues,
P = -1):
ro = rodrigues
if P > 0: ro[1:3] *= -1 # convert from P=1 to P=-1
if not np.isclose(np.linalg.norm(ro[1:3]), 1.0):
raise ValueError('Rodrigues rotation axis is not of unit length.\n{} {} {}'.format(*ro[1:3]))
if ro[0] < 0.0:
raise ValueError('Rodriques rotation angle not positive.\n'.format(ro[0]))
return cls(ro2qu(ro))
# ******************************************************************************************
class Quaternion:
u"""
@ -1383,6 +1727,7 @@ def om2qu(om):
if any(om2ax(om)[0:3]*qu[1:4] < 0.0): print(om2ax(om),qu) # something is wrong here
return qu
def qu2ax(qu):
"""Quaternion to axis angle"""
omega = 2.0 * np.arccos(qu[0])