Computed Expressions

Using Functions as Elements in Computed Expressions

You can use recognized functions as an element in any COMPUTED field expression. A function performs an operation that returns a value. The "VA FileMan Functions" chapter describes the set of functions supplied with VA FileMan; these functions are available to all users. Functions can also be added by making entries in the FUNCTION file (#.5). If you examine this file, you will know all of the functions available to you.

NOTE: The "VA FileMan Programmer Manual" describes how to add functions in the "VA FileMan Functions (Creating)" chapter.

Some functions require an argument or arguments; others are argumentless. The arguments of the function can be any element, including field name, field number (preceded with the #), quoted literal, or even other functions. The SQUAREROOT function, for example, would take an argument that evaluated to '64' and return '8'. Thus, if the AGE field of a patient has the value 64, the expression 'SQUAREROOT(AGE)' would equal 8.

MUMPS Functions ($ASCII, $EXTRACT, $RANDOM, etc.) can also be used as computed-expression Functions.  Thus, $P(NAME,",",1) will return, in the PATIENT File, the Patient's last name.  MUMPS Functions must be abbreviated by their initial character; "$PIECE" won't work.  The FileMan "TRANSLATE" Function is equivalent to MUMPS "$TRANSLATE".

NOTE: You can find the syntax and description of the functions exported with VA FileMan in the "VA FileMan Functions" chapter.

Reviewed/Updated: March 10,2008