def centerAndMomentOfInertia(self, conf=None):
"""
:param conf: a configuration object, or None for the
current configuration
:type conf: :class:~MMTK.ParticleProperties.Configuration or NoneType
:returns: the center of mass and the moment of inertia tensor
in the given configuration
"""
from Scientific.Geometry import delta
offset = None
universe = self.universe()
if universe is not None:
offset = universe.contiguousObjectOffset([self], conf)
m = 0.
mr = Vector(0., 0., 0.)
t = Tensor(3 * [3 * [0.]])
for a in self.atomIterator():
ma = a._mass
if offset is None:
r = a.position(conf)
else:
r = a.position(conf) + offset[a]
m += ma
mr += ma * r
t += ma * r.dyadicProduct(r)
cm = mr / m
t -= m * cm.dyadicProduct(cm)
t = t.trace() * delta - t
return cm, t
def centerAndMomentOfInertia(self, conf = None):
"""
:param conf: a configuration object, or None for the
current configuration
:type conf: :class:`~MMTK.ParticleProperties.Configuration` or NoneType
:returns: the center of mass and the moment of inertia tensor
in the given configuration
"""
from Scientific.Geometry import delta
offset = None
universe = self.universe()
if universe is not None:
offset = universe.contiguousObjectOffset([self], conf)
m = 0.
mr = Vector(0.,0.,0.)
t = Tensor(3*[3*[0.]])
for a in self.atomIterator():
ma = a._mass
if offset is None:
r = a.position(conf)
else:
r = a.position(conf)+offset[a]
m += ma
mr += ma*r
t += ma*r.dyadicProduct(r)
cm = mr/m
t -= m*cm.dyadicProduct(cm)
t = t.trace()*delta - t
return cm, t
def centerAndMomentOfInertia(self, conf = None):
"Returns the center of mass and the moment of inertia tensor."
from Scientific.Geometry.TensorModule import delta
offset = None
universe = self.universe()
if universe is not None:
offset = universe.contiguousObjectOffset([self], conf)
m = 0.
mr = Vector(0.,0.,0.)
t = Tensor(3*[3*[0.]])
for a in self.atomList():
ma = a._mass
if offset is None:
r = a.position(conf)
else:
r = a.position(conf)+offset[a]
m = m + ma
mr = mr + ma*r
t = t + ma*r.dyadicProduct(r)
cm = mr/m
t = t - m*cm.dyadicProduct(cm)
t = t.trace()*delta - t
return cm, t
def centerAndMomentOfInertia(self, conf=None):
"Returns the center of mass and the moment of inertia tensor."
from Scientific.Geometry import delta
offset = None
universe = self.universe()
if universe is not None:
offset = universe.contiguousObjectOffset([self], conf)
m = 0.
mr = Vector(0., 0., 0.)
t = Tensor(3 * [3 * [0.]])
for a in self.atomList():
ma = a._mass
if offset is None:
r = a.position(conf)
else:
r = a.position(conf) + offset[a]
m = m + ma
mr = mr + ma * r
t = t + ma * r.dyadicProduct(r)
cm = mr / m
t = t - m * cm.dyadicProduct(cm)
t = t.trace() * delta - t
return cm, t