Computes a selected operation between multiple \c fieldValue function
objects.
The operation is applied to all results of each \c fieldValue object.
Note
Each object must generate the same number and type of results.
Usage
Minimal example by using \c system/controlDict.functions:
multiFieldValue1
{
// Mandatory entries (unmodifiable)
type multiFieldValue;
libs (fieldFunctionObjects);
// Mandatory entries (runtime modifiable)
operation subtract;
// List of fieldValue function objects as dictionaries
functions
{
region1
{
...
}
region2
{
...
}
...
regionN
{
...
}
}
// Optional (inherited) entries
...
}
where the entries mean:
Property | Description | Type | Req'd | Dflt
type | Type name: multiFieldValue | word | yes | -
libs | Library name: fieldFunctionObjects | word | yes | -
operation | Operation type to apply to values | word | yes | -
functions | List of fieldValue function objects | dict | yes | -
\endtable
Options for the \c operation entry:
add | add
subtract | subtract
min | minimum
max | maximum
average | average
Deprecated fieldValueDelta
- The fieldValueDelta function object was originally written to compute the
difference between two fieldValue-type function objects. The multiFieldValue
object name better describes its purpose whilst being able to operate on an
arbitrary number of fieldValue-type objects.
- weight fields are combined by multiplication
- volFieldValue:
* 0-N scalar fields
- surfaceFieldValue:
* 0-N scalar fields
* 0-1 vector fields
In some cases this can be used to avoid creating additional
fields.
weightFields (rho U);
vs.
derivedFields (rhoU);
weightField rhoU;
- originally (incorrectly) was a Field(0.0), which was generalized
to Field(Zero), but Field() is the correct form
STYLE: rename 'mustGet' to more standard 'mandatory' variable
ENH: update libs of etc/caseDicts/postProcess items
ENH: ensure destructor=default
ENH: ensure constness
ENH: ensure no 'copy construct' and 'no copy assignment' exist
TUT: add examples of function objects with full set
of settings into a TUT if unavailable
TUT: update pisoFoam/RAS/cavity tutorial in terms of usage
- implemented as lazy evaluation with an additional update() method.
This avoids unnecessary changes until the values are actually
required.
- apply mesh motion changes for momentum, volFieldValue,
specieReactionRates function objects
- more dictionary-like methods, enforce keyType::LITERAL for all
lookups to avoid any spurious keyword matching.
- new readEntry, readIfPresent methods
- The get() method replaces the now deprecate lookup() method.
- Deprecate lookupOrFailsafe()
Failsafe behaviour is now an optional parameter for lookupOrDefault,
which makes it easier to tailor behaviour at runtime.
- output of the names is now always flatted without line-breaks.
Thus,
os << flatOutput(someEnumNames.names()) << nl;
os << someEnumNames << nl;
both generate the same output.
- Constructor now uses C-string (const char*) directly instead of
Foam::word in its initializer_list.
- Remove special enum + initializer_list constructor form since
it can create unbounded lookup indices.
- Removd old hasEnum, hasName forms that were provided during initial
transition from NamedEnum.
- Added static_assert on Enum contents to restrict to enum or
integral values. Should not likely be using this class to enumerate
other things since it internally uses an 'int' for its values.
Changed volumeType accordingly to enumerate on its type (enum),
not the class itself.
- affects surfaceFieldValue, volFieldValue.
Use 'none' (if desired) to explicitly suppress the weightField, but
generally better to use a different operation.
- can be useful either for flow-rate weighting where backflow
is to be ignored in the average, or for flow-rate weighting
on surfaces with inconsistent orientation.
Reworked to code to make better use of Enum (the NamedEnum
replacement). Enum doesn't require contiguous enumeration values,
which lets us use bitmasking of similar operations to reduce
duplicate code.
- this makes it possible to perform additional operations
on surface values that have been previously sampled.
- support vectorField for weighting operations.
- reduce overhead by avoiding creation of weight fields, Sf fields
and combined surface geometries unless they are actually required.
- extend some similar concepts and operations to volFieldValue