column relationship value filter_or_append order a <= 0.3 filter 1 b == abc append 2 c <= 0.3 filter 3 #### if (eval "$hash{$filter[0]->[0]} $filter[0]->[1] $filter[0]->[2]") { if (eval $hash{$filter[1]->[0]} $filter[1]->[1] $filter[1]->[2]) { if (eval "$hash{$filter[2]->[0]} $filter[2]->[1] $filter[2]->[2]") { print OUTFILE $line, "\n"; } } }