Program Composition Notation (PCN) is a specification notation for building up larger programs from smaller modules or programs (usually written in C or Fortran). Efficient parallel programming is at the heart of PCN. Larger composed programs are intended to execute efficiently on single-processor machines,

multiprocessor Multiprocessing is the use of two or more central processing units (CPUs) within a single computer system. The term also refers to the ability of a system to support more than one processor or the ability to allocate tasks between them. There ar ...

s with shared memory or distributed multicomputers. PCN was developed at

Argonne National Laboratory Argonne National Laboratory is a science and engineering research national laboratory operated by UChicago Argonne LLC for the United States Department of Energy. The facility is located in Lemont, Illinois, outside of Chicago, and is the lar ...

and the

California Institute of Technology The California Institute of Technology (branded as Caltech or CIT)The university itself only spells its short form as "Caltech"; the institution considers other spellings such a"Cal Tech" and "CalTech" incorrect. The institute is also occasional ...

. PCN includes the language for specifying concurrent algorithms and interfaces to C and Fortran. There is also a PCN toolkit for workstations that allows applications to be developed for supercomputers which includes debugging and performance analysis tools. PCN is appropriate for applications benefiting from parallel computing such as

fluid dynamics In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including '' aerodynamics'' (the study of air and other gases in motion) ...

, and

climate modelling Numerical climate models use quantitative methods to simulate the interactions of the important drivers of climate, including atmosphere, oceans, land surface and ice. They are used for a variety of purposes from study of the dynamics of the c ...

Sources

*Chandy, K. Mani and Taylor, Stephen (1990),
A Primer for Program Composition Notation
'. Technical Report. California Institute of Technology. altechCSTR:1990.cs-tr-90-10br>PCN article in the Free Online Dictionary of Computing
{{Parallel Computing Parallel computing