Action RDn is used in the report design facility only.
When action RDn is used the following steps occur:

• The current report image is "rolled downwards" by "n" lines within the current workstation window.
• A message is displayed on line 24 indicating what lines of the report image are now being viewed.

Some points about "windowing" are as follows:

• The "window" over the report image is required because very often report image dimensions exceed the dimensions of a workstation screen in both width and length.
• The workstation screen is considered to be a "window" through which the full report image can be viewed. Since the report image is larger than the workstation "window" it is necessary to move the "window" around to view various parts of the report image.
• RDn is the action used to move the report image downwards by "n" lines within the current window.
• If no value for "n" is specified (i.e. action RD is entered) a default value of (workstation length - 2) is used. This default value causes the uppermost line in the current window to become the lowermost line in the new window.
• Where the "n" value specified (or defaulted) would cause a movement beyond line 1 of the report image, the first line of the report image will be displayed as the first line in the new window.