VARIOWIN. Software for spatial data analysis in 2D. VARIOWIN is a collection of four Windows programs – Prevar2D, Vario2D with PCF, Model and Grid Display – that are used for spatial data analysis and variogram modelling of irregularly spaced data in two dimensions. Prevar2D builds a pair comparison file (PCF), that is, a binary file containing pairs of data sorted in terms of increasing distance. Pair comparison files can be built from subsets in order to reduce memory requirements. Vario2D with PCF is used for spatial data analysis of 2D data. It uses an ASCII file and a binary pair comparison file produced by Prevar2D.