def _getWeight(self, var, transientGeomCoeff=None, diffusionGeomCoeff=None):
"""
Test for a bug due to the sign operator not being updating
correctly.
>>> from fipy import *
>>> m = Grid1D(nx=1)
>>> v = CellVariable(mesh=m, value=1.)
>>> eq = TransientTerm() == ImplicitSourceTerm(v)
>>> eq.solve(v, dt=1.)
>>> print(v)
[ 2.]
>>> v.setValue(-1.)
>>> eq.solve(v, dt=1.)
>>> print(v)
[-0.5]
"""
coeff = self._getGeomCoeff(var)
diagonalSign = self._getDiagonalSign(transientGeomCoeff, diffusionGeomCoeff)
combinedSign = numerix.array(diagonalSign)[..., numerix.newaxis] * numerix.sign(coeff)
return {'diagonal' : (combinedSign >= 0),
'old value' : numerix.zeros(var.shape, 'd'),
'b vector' : -var * (combinedSign < 0),
'new value' : numerix.zeros(var.shape, 'd')}
def _getWeight(self,
var,
transientGeomCoeff=None,
diffusionGeomCoeff=None):
"""
Test for a bug due to the sign operator not being updating
correctly.
>>> from fipy import *
>>> m = Grid1D(nx=1)
>>> v = CellVariable(mesh=m, value=1.)
>>> eq = TransientTerm() == ImplicitSourceTerm(v)
>>> eq.solve(v, dt=1.)
>>> print v
[ 2.]
>>> v.setValue(-1.)
>>> eq.solve(v, dt=1.)
>>> print v
[-0.5]
"""
coeff = self._getGeomCoeff(var)
diagonalSign = self._getDiagonalSign(transientGeomCoeff,
diffusionGeomCoeff)
combinedSign = numerix.array(diagonalSign)[
..., numerix.newaxis] * numerix.sign(coeff)
return {
'diagonal': (combinedSign >= 0),
'old value': numerix.zeros(var.shape, 'd'),
'b vector': -var * (combinedSign < 0),
'new value': numerix.zeros(var.shape, 'd')
}
def _buildMatrix(self, var, SparseMatrix, boundaryConditions=(), dt=1., equation=None):
"""Implicit portion considers
"""
mesh = var.getMesh()
id1, id2 = mesh._getAdjacentCellIDs()
interiorFaces = numerix.nonzero(mesh.getInteriorFaces())[0]
id1 = numerix.take(id1, interiorFaces)
id2 = numerix.take(id2, interiorFaces)
N = len(var)
b = numerix.zeros((N),'d')
L = SparseMatrix(size = N)
if equation is not None:
from fipy.tools.numerix import sign, add
self._diagonalSign.setValue(sign(add.reduce(equation.matrix.takeDiagonal())))
else:
self._diagonalSign.setValue(1)
weight = self._getWeight(mesh, equation=equation)
if weight.has_key('implicit'):
self._implicitBuildMatrix(SparseMatrix, L, id1, id2, b, weight['implicit'], mesh, boundaryConditions, interiorFaces, dt)
if weight.has_key('explicit'):
self._explicitBuildMatrix(SparseMatrix, var.getOld(), id1, id2, b, weight['explicit'], mesh, boundaryConditions, interiorFaces, dt)
return (L, b)
def _calcCoeffVectors(self, var, equation=None):
"""
Test for a bug due to the sign operator not being updating
correctly.
>>> from fipy import *
>>> m = Grid1D(nx=1)
>>> v = CellVariable(mesh=m, value=1.)
>>> eq = TransientTerm() == ImplicitSourceTerm(v)
>>> eq.solve(v)
>>> print v
[ 2.]
>>> v.setValue(-1.)
>>> eq.solve(v)
>>> print v
[-0.5]
"""
coeff = self._getGeomCoeff(var.getMesh())
from fipy.tools.numerix import sign
combinedSign = self._diagonalSign * sign(coeff)
self.coeffVectors = {
'diagonal': coeff * (combinedSign >= 0),
'old value': numerix.zeros(var.getMesh().getNumberOfCells(), 'd'),
'b vector': -coeff * var * (combinedSign < 0),
'new value': numerix.zeros(var.getMesh().getNumberOfCells(), 'd')
}
def __call__(self, x, pos=None):
'Return the format for tick val x at position pos'
vmin, vmax = self.axis.get_view_interval()
d = abs(vmax - vmin)
b = self._base
# only label the decades
sgn = numerix.sign(x)
x = abs(x)
x += self.threshold
isDecade = ticker.is_decade(x)
bx = b**x
sgnbx = sgn * bx
if not isDecade and self.labelOnlyBase: s = ''
elif x > 4: s = '%+1.0e' % sgnbx
elif x < 0: s = '%+1.0e' % sgnbx
else: s = self.pprint_val(sgnbx, d)
return s
def __call__(self, x, pos=None):
'Return the format for tick val x at position pos'
vmin, vmax = self.axis.get_view_interval()
d = abs(vmax - vmin)
b=self._base
# only label the decades
sgn = numerix.sign(x)
x = abs(x)
x += self.threshold
isDecade = ticker.is_decade(x)
bx = b**x
sgnbx = sgn * bx
if not isDecade and self.labelOnlyBase: s = ''
elif x > 4: s= '%+1.0e' % sgnbx
elif x < 0: s = '%+1.0e' % sgnbx
else : s = self.pprint_val(sgnbx, d)
return s
def _buildMatrix(self, var, SparseMatrix, boundaryConditions=(), dt=1., equation=None):
N = len(var)
b = numerix.zeros((N),'d')
L = SparseMatrix(size=N)
# The sign of the matrix diagonal doesn't seem likely to change
# after initialization, but who knows?
if equation is not None:
from fipy.tools.numerix import sign, add
self._diagonalSign.setValue(sign(add.reduce(equation.matrix.takeDiagonal())))
else:
self._diagonalSign.setValue(1)
coeffVectors = self._getCoeffVectors(var=var)
inline._optionalInline(self._buildMatrixIn, self._buildMatrixPy, L, var.getOld(), b, dt, coeffVectors)
return (L, b)
def sign(self):
return self._UnaryOperatorVariable(lambda a: numerix.sign(a), canInline=False)
