#include <stdio.h>
#include <math.h>

main(int argc, char *argv[]) {
/****************************************************************
  multiply_basin_param.c    Keith Cherkauer    August 14, 1998

  This program was written to read a runfile mask and multiply
  parameters in the activated grid cells by the given value.
****************************************************************/

  FILE *frun, *foldparam, *fnewparam;
  int   i, j, ncol, nrow;
  int   runflag;
  char  tmpstr[512];
  float multfact;
  float param;

  if(argc!=5) {
    fprintf(stderr,"Usage: %s <run mask> <old param file> <new param file> <factor>\n",argv[0]);
    fprintf(stderr,"\tThis program multiplies the parameters for the activated grid cells in the old parameter file by the given value, and writes the results to the new parameter file.  Activated cells have values other than 0 in the run mask file.\n");
    exit(0);
  }

  if((frun=fopen(argv[1],"r"))==NULL) {
    fprintf(stderr,"ERROR: Unable to open %s\n",argv[1]);
    exit(0);
  }

  if((foldparam=fopen(argv[2],"r"))==NULL) {
    fprintf(stderr,"ERROR: Unable to open %s\n",argv[2]);
    exit(0);
  }

  if((fnewparam=fopen(argv[3],"w"))==NULL) {
    fprintf(stderr,"ERROR: Unable to open %s\n",argv[3]);
    exit(0);
  }

  multfact = atof(argv[4]);

  /** Skip and copy header **/
  for(i=0;i<6;i++) {
    fgets(tmpstr,512,frun);
    fgets(tmpstr,512,foldparam);
    if(i==0) sscanf(tmpstr,"%*s %i",&ncol);
    if(i==1) sscanf(tmpstr,"%*s %i",&nrow);
    fprintf(fnewparam,"%s",tmpstr);
  }

  for(i=0;i<nrow;i++) {
    for(j=0;j<ncol;j++) {
      fscanf(frun,"%i",&runflag);
      fscanf(foldparam,"%f",&param);
      if(runflag!=0) {
	fprintf(fnewparam,"%f",param*multfact);
      }
      else {
	fprintf(fnewparam,"%f",param);
      }
      if(j==ncol-1) fprintf(fnewparam,"\n");
      else fprintf(fnewparam," ");
    }
  }
}