Unit
UnitPrefix
Quantity
Variable
Constant
UniqueConstant
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QuantityClusters are classes which collect more other Quantities. Such clusters may be homogeneous (i.e., the types of the contained Quantities are all the same) or heterogeneous (i.e., the types of the contained Quantities may differ).
A VariableCluster is a collection of numerical values which individually are characterized by a unit and a dimension (quantities, see classes of the Quantity package). Such values can be treated by quantity calculus. In the Quantity package, each distinguishable quantity has its own set of units and constitutes a C++ type.
A VariableVector is a homogeneous collection of such values, i.e. it consists of values of the same quantity. In order to save ressources the collection is NOT a vector of objects of the corresponding Quantity type. Rather, the values are stored as double values recalculated each to a common unit. The values can be retrieved in each unit which belongs to the unit set of the quantity in question.
A VariableVectorTuple is a non-homogeneous collection of VariableVectors of equal length. Thus, the VariableVectors can be based on different types of quantities. Equal length ensures that it is always possible to retrieve a set of one value each from each vector as a common tuple of the corresponding quantities. An example would be the two or three coordinates of a point in a two- or three-dimensional space, respectively.
Other clusters, which have not been implemented yet are a VariableMatrix and a VariableTable.
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1.3.6