INTRODUCTION

Fortran is generally accepted as the most universal computer language for computational physics. However, for general programming, it has been surpassed by C. Ratfor is Fortran with C-like syntax. Ratfor was invented by the Kernighan and Plauger1976, the same people who invented C. Ratfor uses C-like syntax, the syntax that is also found in the popular languages C++, Perl, and Java. Ratfor source is approximately 25-30% smaller than the equivalent Fortran source, so it is equivalently more readable.

Recently SEP has been shifting to the newest version of Fortran, Fortran90 Clapp and Crawley (1996); Fomel and Claerbout (1996). Fortran90 allows for dynamic memory allocation and adds useful programming features such as structures, but still forces a verbose coding style. To take advantage of Fortran90's new features, while maintaining the concise coding style provided by Ratfor, we wrote a new Ratfor preprocessor, Ratfor90, which produces Fortran90 rather than Fortran77 code. The newest Ratfor ``compiler'', Ratfor90, is a simple word-processing program (written in Perl and freely distributed) that inputs an attractive Fortran-like dialect and outputs Fortran90.