Partial evaluation is a technique traditionally used in compilation. We have adapted this technique to the undestanding of scientific application programs during their maintenance and we have implemented a tool. This tool analyzes Fortran 90 programs and performs an interprocedural pointer analysis. This paper presents how we have specified this analysis with different formalisms (inference rules with global definitions and set and relational operators). Then we present the tool implementing these specifications. It has been implemented in a generic programming environment and a graphical inetrface has been developped to visualize the information computed during the partial evaluation.