Numeric expression

The "num-expr" or "numeric expression" parameter represents one of five kinds of numeric elements: conditional expressions, numeric constants, numeric variables, numeric system functions, and numeric user-defined functions. See each definition in this section for more information about conditional expressions, numeric constants and numeric variables. See Functions for more information about numeric system functions. See the DEF statement discussion for more information about user-defined functions.

numeric expression
{<number>|<numeric variable>|<numeric internal function>|<numeric user-defined function>|<conditional expression>}
 
number
<A rational number up to 15 digits long>. See RD in BRConfig.sys.

numeric variable
<1-30 alphanumeric characters and underscores, the first of which must be a letter (but not FN). They also cannot be reserved words> 
 
numeric internal function
<An internal function which produces a numeric value>
 
numeric user-defined function
<A user defined function that returns a numeric value>