====== MATC Examples ======
Here some hints on how to deploy Elmer's internal scripting language MATC are shown. For a deeper introduction to MATC, see the [[ftp://ftp.funet.fi/index/elmer/doc/MATCManual.pdf|MATC manual]].

===== General structure of a MATC function =====
A MATC function can be used if there is the need for a more complex syntax (like if-cases) that would render an in-line MATC directive too complicated. Functions are declared outside any section in the SIF with the general syntax:
<code>$ function name(argument){\
contents of function;\
_name = result;\
}</code>
The syntax is very close to C. The argument can also be an array of variables. The call within, for instance, a boundary condition section in the SIF then would be:
<code>
DependentVariableName = Variable FirstDependency, SecondDependency
   Real MATC "name(tx)"
</code>
One can also pass a MATC constant, which is defined outside any section block in the SIF by the syntax "$ RHO = 910.0" to the function using the ''import'' argument:
<code>
$ RHO = 910.0

$ function overburden(depth) import RHO {\
_overburden = RHO * depth * 9.81;\
}</code>

===== Passing time or time step size to a function =====
Time as well as time step size are both accessible as variables in Elmer. Dependency of a variable on these could look like 
<code>
DependentVariable = Variable Time, Timestep Size
   Real ...
}</code>