define functions, equations, and algebraic expressions
In most positions within the USER_common_variables in the RightHandSideExpression it is possible to include user defined equations, e.g. into boundary conditions, initial conditions, user defined variables, and many more. The equation is then evaluated on point basis, in particular the equation is automatically evaluated for each the statement on the left hand side concerning point. Equations can be defined and invoked in the following ways:
Many of the equations are evaluated on point basis. The values of physical and organizational quantities can be accessed by the Y-Syntax by an index from __Indices__
__Constants__: Meshfree internal constants, e.g. %BND_free% can be compared to Y%ind_kob% to evaluate if a point belongs to a free surface, see Example 2.
If the equation is not so complicated and only used on one location within the setup, then there is a comfortable way of defining the equation inline by using the inline square bracket []-syntax .
Example 6Most equations are evaluated for the pointcloud, but we also have a limited amount of functions, that can be used in the context of boundary elements.
(e.g. for SAVE_BE_ITEM): these are all functions starting with BE* in the list of Functions.