6.7. Explicitly Computing Derived Quantities

BEGIN DERIVED OUTPUT
  COMPUTE AND STORE VARIABLE =
    <string>derived_quantity_name
END DERIVED OUTPUT

The above command block is used to explicitly compute and store a derived quantity into an internal field. This is useful if the field is needed by an outside capability such as a transfer or error estimation.

For example, to use a derived quantity in a transfer, a DERIVED OUTPUT command block must be used. For instance, to transfer the von Mises stress norm:

BEGIN DERIVED OUTPUT
  COMPUTE AND STORE VARIABLE = von_mises
END DERIVED OUTPUT

Tables Table 9.13 through Table 9.19 in Section 9 list element variables available for different types of elements. Variables that are only computed at user request are designated with a yes in the Derived column of these tables. These are the quantities that must be listed in a BEGIN DERIVED OUTPUT command block if they are to be transferred during a coupled analysis.