Buy article online - an online subscription or single-article purchase is required to access this article.
computer programs
A space-group-general radix-2 crystallographic fast Fourier transform (FFT) has been written in only 130 lines of executable Fortran code. Computational times compare favorably with other FFT programs that require 1000 or more lines of code excluding peak-interpolation routines. The complete program and description of control parameters are given. The program is dimensioned to a maximum grid size of 1283 points and a Miller-index range of ±60. These arrays may be altered by simply changing the values of NPAR and MH in the PARAMETER statements of the program.