ABSTRACT
Parallel application codes depend on maps between global indices and local indices either explicitly or implicitly. Chapter 12 described these maps as the composition of a subpartition operator with a permutation operator. The permutation operator changes the order of global block indices before the partition operator assigns them to local indices. The programmer transcribes formulas for these operations into computer code. These formulas are complicated, however, and transcribing them to computer code is subject to error.
