Data Function Tool Help

Note: more complete help, including screenshots, is available when online.

The Data Function Tool enables a user to create datasets that are functions of other datasets. The input datasets and user data functions all share the same time base (or other base) and data manager.

The tool lists the input datasets in a Variables area starting with the shared base variable. Above the variables area is a dropdown that shows the Name of the data manager and below it is a table of user-defined Functions.

The New and Delete buttons at the bottom make creation and management of functions easy. New functions are given a generic name and assigned the expression "0".

Double-click a cell and enter text to change a Name or Expression. As you edit the field turns yellow until you hit the enter key.

If an unreadable expression is entered into an Expression cell the cell turns red. Function expressions must be valid mathematical expressions using only the variable names listed.

The OSP expression parser recognizes all variables, constants e and pi, standard operators ( + - * / ^ ), boolean operators ( = > < <= >= <> & | ! ), and many common one and two-parameter math functions.

The parser also accepts "if" functions in the form if(conditional statement, expression1, expression2). Expression1 is evaluated if the conditional statement is true and expression2 is evaluated if the conditional statement is false. For example, if (x < 0, x^2, -x^2) is a valid function expression.