SNAP-1D is a computer program for the qualitative and quantitative analysis of powder diffraction data using the full measured data set. As measures of similarity between patterns, non-parametric statistical tests based on Spearman's correlation coefficient and the Kolmogorov-Smirnov test are used. Traditional correlation coefficients based on the Pearson formalism are also employed. This combination, suitably weighted, gives a reliable measure of qualitative pattern similarity. The method can be extended to the quantitative analysis of mixtures by using the above methods in conjunction with singular value decomposition techniques. A full description of the theory with suitable examples has been published elsewhere [Gilmore et al. (2004). J. Appl. Cryst. 37, 231-242]; here the focus is on the computer software itself. The program is commercially available, and runs on PCs under the Windows 2000 and XP operating systems with modest hardware requirements. An easy to use graphical interface is supplied.
Barr, G., Gilmore, C. J., & Paisley, J. (2004). SNAP-1D: A computer program for qualitative and quantitative powder diffraction pattern analysis using the full pattern profile. Journal of Applied Crystallography, 37(4), 665–668. https://doi.org/10.1107/S0021889804011847