Deallocating Arrays

Heap storage can be reclaimed using the DEALLOCATE statement:

    IF (ALLOCATED(ages)) DEALLOCATE(ages,STAT=ierr)

• it is an error to deallocate an array without the ALLOCATE attribute or one that has not been previously allocated space,
• there is an intrinsic function, ALLOCATED, which returns a scalar LOGICAL values reporting on the status of an array,
• the STAT= field is optional but its use is recommended,
• if a procedure containing an allocatable array which does not have the SAVE attribute is exited without the array being DEALLOCATE d then this storage becomes inaccessible.

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