Report progress of some PRTools iterative routines
All progress of all routines will be written to the command window.
Progress reports will be written to the file with file descriptor FID.
Writes progress message to FID. If FID == , the predefined destination (command window or file) is used.
Progress reporting is turned off.
Toggles between PRPROGRESS ON and PRPROGRESS OFF
FID = PRPROGRESS
Retrieves the status of PRPROGRESS
By default, PRPROGRESS is switched off. Interactive progress tracing can be best following by PRWAITBAR