#!/usr/bin/perl -w
#Prgram to check PDB file
#Written by Surendra Negi
# USE:perl PDB.pl InputPDB_file.pdb PDB_CHAIN > OutPDB_file.pdb";
use strict;
print "Please use:: perl PDB.pl InputPDB_file.pdb PDB_CHAIN > OutPDB_file.pdb\n";
my $filename = shift;
my $chainName=shift;
my @In_File=();
open(PDBFILE,"$filename") or dienice(" Can't open sorted data file $!");
@In_File=<PDBFILE>;
chomp(@In_File);
close(PDBFILE);
foreach my $line (@In_File) {
    if( $line =~ /^ATOM\s*./){
    my $rc=substr($line,0, 6);  
    my $sno1=substr($line,6, 5);  
    my $atm1=substr($line,12,4);
    my $prname1=substr($line,17,3);  
    my $sdchai1=substr($line,21,1);  
    my $atomno1=substr($line,22,4); 
    my $x= substr($line, 30, 8); 
    my $y= substr($line, 38, 8); 
    my $z= substr($line, 46, 8);  
    my $occ=substr($line, 57, 3); 
    my $tf=substr($line, 70, 3); 
    if ($sdchai1 eq $chainName){print "$rc$sno1 $atm1 $prname1 $sdchai1$atomno1   $x$y$z      $tf";
    print "\n";}
    }
    }
print "TER\n";
print "END\n";