Hello, I want use the interface between R and C. I usually work in windows. I installed the Rtools.exe and ActivePerl 5.8.8 in the path C:\R\R-2.3.1 like it is in the Appendix F the windows tools (Manual). However, I do not have sucess. How should I do this ? Which type of path should I use? Other question is about how compiling C code using the Dev-C++ and librarys of packages R. For example, I want use the function dnorm and I include in compiler options the library Rmath.h and dnorm.c: #include <stdio.h> #include <Rmath.h> #include <dnorm.c> main() { int a, b, s; printf("Introduza um n?mero:\n"); scanf("%d", &a); printf("Introduza outro n?mero:\n"); scanf("%d", &b); s = a + b; s=dnorm(2,1,1,1); printf("A densidade de %d com %d d? %d\n", a, b, s); system("PAUSE"); } However, this code do not work. thanks the best regard Elisabete Fernandes