# Compare metadata filter output containing float value strings to reference
 # output data. Returns the whole reference data if delta of each value is below
 # threshold, else returns the whole input data.
 
 function abs(val) {
     return ((val < 0.0) ? -val : val);
 }
 
 function max(val1, val2) {
     return ((val1 >= val2) ? val1 : val2);
 }
 
 function is_numeric_str(str) {
     return (str ~ /^[+-]?[0-9]*\.?[0-9]+$/);
 }
 
 BEGIN {
     FS = "=";
     # check for "fuzz" (threshold) program parameter, else use default
     if (fuzz <= 0.0) {
         fuzz = 0.1;
     }
     # check for "ref" (reference file) program parameter
     if (ref) {
         ref_nr = 0;
         while ((getline line < ref) > 0) {
             ref_nr++;
             ref_lines[ref_nr] = line;
             if (split(line, fields) == 2 && is_numeric_str(fields[2])) {
                 ref_keys[ref_nr] = fields[1];
                 ref_vals[ref_nr] = fields[2] + 0;  # convert to number
             }
         }
         close(ref);
     }
     delta_max = 0;
     result = (ref ? 1 : 0);
 }
 
 {
     cmp_lines[NR] = $0;
     if (NF == 2 && is_numeric_str($2) && ref_vals[NR]) {
         val = $2 + 0;  # convert to number
         delta = abs((val / ref_vals[NR]) - 1);
         delta_max = max(delta_max, delta);
         result = result && ($1 == ref_keys[NR]) && (delta <= fuzz);
     } else {
         result = result && ($0 == ref_lines[NR]);
     }
 }
 
 END {
     if (result) {
         for (i = 1; i <= ref_nr; i++)
             print ref_lines[i];
     } else {
         for (i = 1; i <= NR; i++)
             print cmp_lines[i];
         if (NR != ref_nr)
             print "[refcmp] lines: " NR " != " ref_nr > "/dev/stderr";
         if (delta_max >= fuzz)
             print "[refcmp] delta_max: " delta_max " >= " fuzz > "/dev/stderr";
     }
 }