millward@m... wrote:
>  Can anyone tell me how to call a FORTRAN 
> routine from within a Linux GNU C program?

You can use f2c, which converts to c code first. As I recall, it works 
something like

# f2c -P file.f
# gcc file.c -c

and to call within C, use

#include<f2c.h>
#include"file.P"

and compile

# gcc cfile.c file.o -lf2c -lm

file.P tells you the function arguments, which are not what you expect.

There may be other ways to link, for example, g77 object files to C 
code, but in any case, you'll need some way of mapping function 
arguments and FORTRAN often has hidden arguments.

> FORTRAN is better for calculations than 
> C and I'd like to mixed the two and see 
> if performance is better than with just 
> plain C. 

I'm not convinced. In any case, you can develop C++ code faster than 
fortran, and very seldom is runtime more valuable than development time.

If you just want scientific routines, try the GNU Scientific Library (in C).


-- 
JDL