#!/bin/awk -f
## Rebin two 2-column (x,y) files on regular grid in x
## Use as: mrebin.awk <file1> <file2> 
## Nov 23, 2004
BEGIN{ xstart = 0; xend = 9; xstep=0.1; xwid = 0.1;
nx = (xend - xstart)/xstep
# nf = ARGC
nf = 3
  for (i=0;i<nx;i++) {
    xr[i] = xstart + i*xstep; 
    for (j=1;j<nf;j++){yr[i,ARGV[j]]=0; wt[i,ARGV[j]]=0;}
  }
 system("rm -f tmp")
}
{
  for (i=0;i<nx;i++) {
    dx = $1 - xr[i]
      if (dx <0) dx = -dx
      if (dx < xwid) {
       yr[i,FILENAME] += $2
       wt[i,FILENAME] +=1
      }
  }
}
END{ 
  for (i=0;i<nx;i++) {    
    if ((wt[i,ARGV[1]] >0) && (wt[i,ARGV[2]] >0)) {    
      print  yr[i,ARGV[1]]/wt[i,ARGV[1]], yr[i,ARGV[2]]/wt[i,ARGV[2]] >"tmp"
	}
      }
  system("xmgrace -param xyrebin.par tmp")
}