#include <stdio.h>
/*extern   FILE *fp;
*/
int plistr(FILE *fp, int n, double *a)
{
   int i, ss=0;
   for (i=1; i<=n; i++) {
      ss=0;
      ss=fscanf(fp,"%le", &a[i-1]);
      if (ss!=1) {
         printf("error in reading list of positive constants.\n"); 
         return 1;
      }
      if (a[i-1]<=0) {
         printf("*** element %3d of list= %15.7e is not positive \n",i,a[i-1]);
         return 1;
      }
   }
   return 0;
}