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20 sub-jobs, each with 1 cpu and 1 8 GB of memory, are generated in according to the total number requested through the #PBS -J option. The $PBS_ARRAY_INDEX environment variable takes on each value in the range specified by the -J option. This variable can be used to identify the directories, created in advance for each input, and the input files needed by the sub-job. For an array-type job, the job itself must be declared re-runnable (#PBS -r y).
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