
A description of the gsaslanguage software is presented. The software provides input to and processes output from the GSAS package. It allows the development of scripts for the automatic evaluation of large numbers of data sets and provides documentation of the refinement strategies employed, thus fostering the development of efficient refinement strategies. Use of the bash shell and standard Unix text-processing tools, available natively on Linux and Mac OSX platforms and via the free cygwin software on Windows systems, make this software platform independent.