Modal & Non-Modal Status of Variables

The modal or non-modal status of variables will determine if and when they are sent to output. When the formats for the 18 format types are set during the DFPost stage in Section 3 of the post processor questions, the last format option allows you to specify the format type as modal or non-modal. The Character format type assigns a modal status, by default. In addition, the status of all variables can be changed with the MODAL or NON-MODAL declaration statement.

An "on/off" indicator is kept for each variable. The system uses this indicator to determine whether or not to send a variable value to output. When modal variables are assigned a new value they are turned "on". Only variables with "on" indicators will be sent to output. After a modal variable is sent to output, its indicator is turned "off". As a result, if a modal variable is sent to output and its value is not changed, the next time the same name is encountered it will not be sent to output.

Non-modal variables are never turned "off". They are sent to output any time their names are encountered in the blocks as part of an OUTPUT statement.

The value of the modal variable has no impact on its operation. Whether the variable represents text, a code or a numeric value, it will not affect the way the "on/off" indicator works.