The usual advantages of a C code versus Fortran code applies here (as of the writing in 1992; Fortran may catch up in future years). In C, one can dynamically allocate memory for structure arrays and matrices as the calculation requires them. The memory is freed when it is no longer needed. This results in a smaller executable file. C code, in general, is easily ported to other types of computers. (So far the program has been ported to various Unix, Linux, and Windows OSs since 1992.) The code is written in a verbose style (i.e., variable names are based on un-abbreviated physical quantity names), which makes it easy for anyone to understand the code.