Cancelling a parameter means that values associated with it are lost. It is most-commonly used for processing in a loop.
If we have a loop in which we wish to get new values for a parameter and do some calculations in each iteration, we must cancel any parameters obtained in the loop, otherwise the first value will be used repeatedly, since the parameter is in the active state.
Here is an illustration. ITER calculations are performed, using the value of parameter REJECT.
DO I = 1, ITER CALL PAR_GET0D( 'REJECT', ABC, STATUS ) < perform calculation involving variable ABC > CALL PAR_CANCL( 'REJECT', STATUS ) END DO
PAR Interface to the ADAM Parameter System