def create_evaluable(expression, fields, materials, variables, integrals,
regions=None,
ebcs=None, epbcs=None, lcbcs=None, ts=None, functions=None,
auto_init=False, mode='eval', extra_args=None,
verbose=True, kwargs=None):
"""
Create evaluable object (equations and corresponding variables)
from the `expression` string.
Parameters
----------
expression : str
The expression to evaluate.
fields : dict
The dictionary of fields used in `variables`.
materials : Materials instance
The materials used in the expression.
variables : Variables instance
The variables used in the expression.
integrals : Integrals instance
The integrals to be used.
regions : Region instance or list of Region instances
The region(s) to be used. If not given, the regions defined
within the fields domain are used.
ebcs : Conditions instance, optional
The essential (Dirichlet) boundary conditions for 'weak'
mode.
epbcs : Conditions instance, optional
The periodic boundary conditions for 'weak'
mode.
lcbcs : Conditions instance, optional
The linear combination boundary conditions for 'weak'
mode.
ts : TimeStepper instance, optional
The time stepper.
functions : Functions instance, optional
The user functions for boundary conditions, materials
etc.
auto_init : bool
Set values of all variables to all zeros.
mode : one of 'eval', 'el_avg', 'qp', 'weak'
The evaluation mode - 'weak' means the finite element
assembling, 'qp' requests the values in quadrature points,
'el_avg' element averages and 'eval' means integration over
each term region.
extra_args : dict, optional
Extra arguments to be passed to terms in the expression.
verbose : bool
If False, reduce verbosity.
kwargs : dict, optional
The variables (dictionary of (variable name) : (Variable
instance)) to be used in the expression.
Returns
-------
equation : Equation instance
The equation that is ready to be evaluated.
variables : Variables instance
The variables used in the equation.
"""
if kwargs is None:
kwargs = {}
if regions is not None:
if isinstance(regions, Region):
regions = [regions]
regions = OneTypeList(Region, regions)
else:
regions = fields[fields.keys()[0]].domain.regions
# Create temporary variables.
aux_vars = Variables(variables)
if extra_args is None:
extra_args = kwargs
else:
extra_args = copy(extra_args)
extra_args.update(kwargs)
if ts is not None:
extra_args.update({'ts' : ts})
equations = Equations.from_conf({'tmp' : expression},
aux_vars, regions, materials, integrals,
user=extra_args, verbose=verbose)
equations.collect_conn_info()
# The true variables used in the expression.
variables = equations.variables
if auto_init:
for var in variables:
var.init_data(step=0)
if mode == 'weak':
equations.time_update(ts, ebcs, epbcs, lcbcs, functions,
verbose=verbose)
else:
setup_extra_data(equations.conn_info)
return equations, variables
def create_evaluable(expression, fields, materials, variables, integrals,
regions=None,
ebcs=None, epbcs=None, lcbcs=None, ts=None, functions=None,
auto_init=False, mode='eval', extra_args=None,
verbose=True, kwargs=None):
"""
Create evaluable object (equations and corresponding variables)
from the `expression` string.
Parameters
----------
expression : str
The expression to evaluate.
fields : dict
The dictionary of fields used in `variables`.
materials : Materials instance
The materials used in the expression.
variables : Variables instance
The variables used in the expression.
integrals : Integrals instance
The integrals to be used.
regions : Region instance or list of Region instances
The region(s) to be used. If not given, the regions defined
within the fields domain are used.
ebcs : Conditions instance, optional
The essential (Dirichlet) boundary conditions for 'weak'
mode.
epbcs : Conditions instance, optional
The periodic boundary conditions for 'weak'
mode.
lcbcs : Conditions instance, optional
The linear combination boundary conditions for 'weak'
mode.
ts : TimeStepper instance, optional
The time stepper.
functions : Functions instance, optional
The user functions for boundary conditions, materials
etc.
auto_init : bool
Set values of all variables to all zeros.
mode : one of 'eval', 'el_avg', 'qp', 'weak'
The evaluation mode - 'weak' means the finite element
assembling, 'qp' requests the values in quadrature points,
'el_avg' element averages and 'eval' means integration over
each term region.
extra_args : dict, optional
Extra arguments to be passed to terms in the expression.
verbose : bool
If False, reduce verbosity.
kwargs : dict, optional
The variables (dictionary of (variable name) : (Variable
instance)) to be used in the expression.
Returns
-------
equation : Equation instance
The equation that is ready to be evaluated.
variables : Variables instance
The variables used in the equation.
"""
if kwargs is None:
kwargs = {}
if regions is not None:
if isinstance(regions, Region):
regions = [regions]
regions = OneTypeList(Region, regions)
else:
regions = fields[fields.keys()[0]].domain.regions
# Create temporary variables.
aux_vars = Variables(variables)
if extra_args is None:
extra_args = kwargs
else:
extra_args = copy(extra_args)
extra_args.update(kwargs)
if ts is not None:
extra_args.update({'ts' : ts})
equations = Equations.from_conf({'tmp' : expression},
aux_vars, regions, materials, integrals,
user=extra_args, verbose=verbose)
equations.collect_conn_info()
# The true variables used in the expression.
variables = equations.variables
if auto_init:
for var in variables:
var.init_data(step=0)
if mode == 'weak':
equations.time_update(ts, ebcs, epbcs, lcbcs, functions,
verbose=verbose)
else:
setup_extra_data(equations.conn_info)
return equations, variables