On Thu, May 15, 2008 at 12:13 PM, ANJAN PURKAYASTHA < [EMAIL PROTECTED]> wrote:
> Hi, > here is a problem I'm working on. It's not PERL-specific, rather it is a > problem in sorting followed by grouping. > Suppose I have a set of lines that have tab-delimited text, thus: > 1 w 3 wer > 2 a 4 rte > 4 w 2 weg > 6 d 4 fhg > 5 d 7 dfl > 6 w 4 ald > 8 a 3 dsl > > I would like to first sort the lines based on the 2nd token (w,a, w, d, > etc) > and then group the lines based on the 2nd token. > > At the end of this sorting/grouping I should have the lines grouped thus: > 2 a 4 rte > 8 a 3 dsl > > 6 d 4 fhg > 5 d 7 dfl > > 1 w 3 wer > 4 w 2 weg > 6 w 4 ald > > > I can figure out the sorting. Are they any command/modules to do the > grouping based on identical tokens? > > appreciate your input. > > > tia, > anjan > > > > -- > ANJAN PURKAYASTHA, PhD. > Senior Computational Biologist > ========================== > > 1101 King Street, Suite 310, > Alexandria, VA 22314. > 703.518.8040 (office) > 703.740.6939 (mobile) > > email: > [EMAIL PROTECTED]; > [EMAIL PROTECTED] > > http://www.vbi.vt.edu > > ========================== > hash of array will solve your problem use strict; use warnings; my %HofA; map { push @{ $HofA{ (split)[1] } }, $_ } <DATA> ; for my $key (sort keys %HofA) { print $_ for @{ $HofA{$key} }; print "\n"; } __DATA__ 1 w 3 wer 2 a 4 rte 4 w 2 weg 6 d 4 fhg 5 d 7 dfl 6 w 4 ald 8 a 3 dsl
