in reply to Scriptome and Perl One-Liners
much of the code in the Scriptome would make an excellent tutorial on Perl one-liners
I would not be so quick about excellence.
Take for example, this page
perl -ne 'BEGIN {$col=1}' -e 's/\r?\n//; @F=split /\t/, $_; $sum += $F +[$col]; END {warn "Sum of column $col for $. lines\n"; print "$sum\n"}' file.t +ab
I see an inefficient replacement of newline, instead of chomp. But since this is a one-liner, the "-l" option will do instead, and it will also save the output newlines.
Then, the @F=split /\t/, $_; could be easily replaced by the "-a" autosplit option, which will happily take charge of different whitespace types, other than tabs.
I would say that this one-liner woult be better written as
perl -e 'BEGIN {$col=1}' -lane '$sum += $F[$col]; END {print "Sum of column $col for $. line: $sum"}' file.tab
Or, I should even dare this:
perl -lane '$sum += $F[1]; END {print $sum}' file.tab
It's shorter, thus easier to write, and less mistakes to make when copying it.
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Re^2: Scriptome and Perl One-Liners
by educated_foo (Vicar) on Oct 31, 2005 at 23:32 UTC |
In Section
Meditations