OOF2: The Manual

TwoVectorField
	Field Classes and Functions

Name

TwoVectorField — A two dimensional vector-valued Field object

Synopses

Only functions relevant to people writing OOF2 extensions are listed here. Base class functions are described in the Field and CompoundField documentation.

C++ Synopsis

#include "engine/field.h"

class TwoVectorField: , public CompoundField {
  virtual FieldIndex* getIndex(const std::string& name) const;
  DoubleVec values(const FEMesh* mesh,
                   const Element* element,
                   const MasterPosition& position);
  DoubleVec gradients(const FEMesh* mesh,
                      const Element* element,
                      const MasterPosition& position,
                      SpaceIndex direction);
}

Python Synopsis

from ooflib.SWIG.engine.field import TwoVectorField

class TwoVectorField(CompoundField):
  def __init__(self, name)
  def getIndex(self, name)

Source Files

SRC/engine/field.h: C++ header
SRC/engine/field.C: C++ code
SRC/engine/field.swg: SWIG source code
SRC/engine/field.spy: python code included in field.swg.

Description

TwoVectorField is a Field whose value is a two dimensional (in-plane) vector at every point in a Mesh. TwoVectorFields should always be constructed in Python (see Section 8.3). The constructor has a single argument, which is the name of the Field.

Because TwoVectorField is a CompoundField, when it is constructed its out-of-plane and time derivative parts will be constructed automatically. The out-of-plane part of a TwoVectorField field is a ThreeVectorField, the three dimensional gradient of its z component.

It is not necessary to keep an explicit reference to a newly constructed TwoVectorField. Existing fields may be retrieved with getField.

The FieldIndex class for TwoVectorField is VectorFieldIndex. The Components class is VectorFieldComponents, and the ComponentIterator is VectorFieldIterator.

Methods

`FieldIndex *getIndex(const std::string &name) const`

TwoVectorField::getIndex() returns a pointer to a VectorFieldIndex. The name argument can be "x" or "y".

`DoubleVec values(...) const`

DoubleVec values(const FEMesh* mesh, const Element* element, const MasterPosition& point) const;

values() is a non-virtual method that returns all (that is, both) components of a TwoVectorField in a vector at the given point within the given element.

To retrieve Field values from a generic Field* pointer, either cast the pointer to the derived type and call values():

DoubleVec vals = dynamic_cast<const TwoVectorField*>(field)->values(mesh, element, point);

or access the components individually via the Field base class methods:

DoubleVec vals(field->ndof());
for(IndexP i : *field->components())
  vals[i.integer()] = field->value(mesh, element, point, i);

`DoubleVec gradients(...) const`

DoubleVec gradients(const FEMesh* mesh, const Element* element, const MasterPosition& point, SpaceIndex direction) const;

gradients() is just like values(), but it returns the components of the gradients in the given direction. That is, gradients(mesh, element, x, j) returns a vector whose $i^{\mathrm{th}}$ component is the $j$ -derivative of the $i^{\mathrm{th}}$ component of the TwoVectorField.


ScalarField		ThreeVectorField