PDDP: A Data Parallel Programming Language Tool <description><url>http://www.nersc.gov/doc/Parallel_Processing/pddp.html</url> The Parallel Data Distribution Preprocessor (PDDP) language translator provides a model similar to High Performance Fortran compilers for users of massively parallel Multiple Instruction Multiple Data computers. In the absence of High Performance Fortran compilers, PDDP allows scientists using HPF-like coding to quickly port their codes to massively parallel computers. Our Parallel Data Distribution Preprocessor (PDDP) model provides an HPF-subset offering efficient performance on massively parallel processors (MPPs) with nonuniform memory access (NUMA). When HPF compilers do arrive, PDDP codes will require few changes. PDDP is a simple model that separates the layout of data from the actual algorithm, allowing the algorithm to be described in Fortran 90 array syntax notation. <keywords>parallel programming language; data parallelism; massively parallel multiprocessor; nonuniform memory access; HPF <category>ppt-pplang <contact>Brent C. Gorda, 510-424-4147 / brent@nersc.gov <contact>Karen Warren, 510-422-9022 / kwarren@nersc.gov </urc>