Math File

Use the Project > Scripting > Math File menu option (MATHFILE GX) to apply a mathematical expression to channels in a database. The expression is defined in an expression file.

Math File dialog options

Math expression file (.EXP)

name of the file that contains the expression (.EXP assumed).

Script Parameter: MATHFILE.EXP

Application Notes

The MATHFILE GX is similar to the MATH GX except that the expression to be evaluated is read from a file. The file may contain many lines of expressions and blank or comment lines. Comment lines are indicated by a '/' character as the first character of the line. For example, following is an expression file for squaring the sum of two channels:

Channel D will be the square of the sum of A and B: @sum = A + B; D = @sum * @sum;

Each expression must end with a ';' character. You can place more than one expression on a line as long as each expression ends with a ';'.

Note that each occurrence of a channel name in an expression requires a significant amount of memory in order for the software to evaluate the expression (currently 4096 bytes per channel). As a result, complex expressions may run out of memory. Use a temporary variable whenever possible (@sum is a temporary variable in the above example). You can also use OS, the script processor, to evaluate very complex expressions. OS has considerably more memory available for processing than IE.