I try used perl script to get characters from data: #!/usr/bin/perl -w use v5.14; while (<DATA>){ chomp; my $line = ''; $line = (split //,@_)[5]; print "it is $line.\n"; }
__DATA__ Danio rerio strain Tuebingen chromosome 1 GRCz11 Primary Assembly Danio rerio strain Tuebingen chromosome 2 GRCz11 Primary Assembly the results is : Use of uninitialized value $line in concatenation (.) or string at foundins.pl line 9, <DATA> line 1. it is . Use of uninitialized value $line in concatenation (.) or string at foundins.pl line 9, <DATA> line 2. it is . the aim for the work is to get the number for each line such as: 1 for first line and 2 for second lin how can I correct my perl script?