#sub function to write input file data into csv format
sub readout_file {
    ($filename) = @_;
    open my $fh, '<', $filename or die "can't open file:$!";
    while (<$fh>) {
        chomp;
        s/ /,/g;        ## OR s/ /,/g; if you want
		@linecolumns=split(',',$_);

		$filename =~ s/.*\///;
		$filename =~ s/\.[^.]+$//;
		push(@filenames, $filename);
	}
 }