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Reference documentation for deal.II version 9.6.0
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#include <deal.II/fe/fe_values_extractors.h>
Public Member Functions | |
Vector () | |
Vector (const unsigned int first_vector_component) | |
std::string | get_name () const |
Public Attributes | |
unsigned int | first_vector_component |
Extractor for a vector of spacedim
components of a vector-valued element. The value of spacedim
is defined by the FEValues object the extractor is applied to. The result of applying an object of this type to an FEValues, FEFaceValues or FESubfaceValues object is of type FEValuesViews::Vector.
The concept of extractors is defined in the documentation of the namespace FEValuesExtractors and in the Handling vector valued problems topic.
Note that in the current context, a vector is meant in the sense physics uses it: it has spacedim
components that behave in specific ways under coordinate system transformations. Examples include velocity or displacement fields. This is opposed to how mathematics uses the word "vector" (and how we use this word in other contexts in the library, for example in the Vector class), where it really stands for a collection of numbers. An example of this latter use of the word could be the set of concentrations of chemical species in a flame; however, these are really just a collection of scalar variables, since they do not change if the coordinate system is rotated, unlike the components of a velocity vector, and consequently, this class should not be used for this context.
Definition at line 149 of file fe_values_extractors.h.
Default constructor. Initialize the object with an invalid component. This leads to an object that can not be used, but it allows objects of this kind to be put into arrays that require a default constructor upon resizing the array, and then later assigning a suitable object to each element of the array.
Definition at line 326 of file fe_values_extractors.h.
Constructor. Take the first component of the selected vector inside the FEValues object as argument.
Definition at line 331 of file fe_values_extractors.h.
std::string Vector< Number >::get_name | ( | ) | const |
Return a string that uniquely identifies this finite element extractor.
Definition at line 31 of file fe_values_extractors.cc.
unsigned int FEValuesExtractors::Vector::first_vector_component |
The first component of the vector view.
Definition at line 154 of file fe_values_extractors.h.