Automated computation and consistency checking of physical dimensions and units in scientific programs

Physical dimensions and units form an essential part of the specification o f constants and variables occurring in scientific programs, yet no standard compilable programming language implements direct support for automated di mensional consistency checking and unit conversion. This paper describes a conceptual basis and prototype implementation for such support within the f ramework of the standard Fortran 90 language. This is accomplished via an e xternal module supplying appropriate user data types and operator interface s. Legacy Fortran 77 scientific software can be easily modified to compile and run as `dimension-aware' programs utilizing the proposed enhancements. Copyright (C) 2001 John Wiley & Sons, Ltd.