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Section 10.2: Error Messages Up Main page Section A.1: Math parameters

# A Heterogeneous model parameters

Many model parameters can be made dependent on the reference coordinates. This is useful, for instance, for defining inhomogeneous materials. There are two mechanisms for creating heterogeneous parameters: a mathematical expression, or a map. The type of the parameter is set via the type attribute, which can take on two values.
 type description math Define a math parameter via a mathematical expression map Define a mapped parameter const Define a constant parameter (default)
The two types of parameters are described in more detail in the sections below.
The type attribute can be omitted. In that case, it is assumed to be a const parameter, unless the tag's value is not a number. In that case, it is assumed to be a math parameter.
Section 10.2: Error Messages Up Main page Section A.1: Math parameters