[R] library file for R's nmath routines

[José Matos]

I guess that you intended to send this message to the list. :-)

On 02/03/06, Globe Trotter <itsme_410 at yahoo.com> wrote:
> Hi,
>
> Thanks, everyone for all the help! So, here is my calling function in C (called
> test.c):
>
>
>
> #include<stdio.h>
> #include<stdlib.h>
> #include<Rmath.h>
>
>
> int main(void) {
>   printf("%f \n",pchisq(2.,7., 1, 0));
>   printf("%f \n",pnchisq(2.,7.,0., 1, 0));
>   return EXIT_SUCCESS;
> }
>
>
> I compile using:
>
>  gcc test.c -I/usr/lib/R/include -L/usr/lib/R/lib -lm -lR

  Why do you link against libm?

  Shouldn't it be
gcc test.c -I/usr/lib/R/include -L/usr/lib/R/lib -lRmath -lR
?

> However, running
> ./a.out
>
> gives me:
>
> 1.000000
> 0.040160
>
> The first is wrong, but the second non-central is correct, and matches the
> answer from R.
>
> Incidentally, pgamma (which is what pchisq calls, as per the C program inside
> R) is also wrong and not surprisingly, gives the same answer as above.
>
> Any suggestions?
>
> Many thanks!


--
José Matos