Beefy Boxes and Bandwidth Generously Provided by pair Networks
Perl Monk, Perl Meditation
 
PerlMonks  

Re^2: Efficient way to replace a set of values with another set of values

by Arunbear (Parson)
on Nov 23, 2012 at 10:48 UTC ( #1005246=note: print w/replies, xml ) Need Help??


in reply to Re: Efficient way to replace a set of values with another set of values
in thread Efficient way to replace a set of values with another set of values

Command line version:
perl -pi -e 's/^(\d)/chr($1+96)/e' myfile
  • Comment on Re^2: Efficient way to replace a set of values with another set of values
  • Download Code

Replies are listed 'Best First'.
Re^3: Efficient way to replace a set of values with another set of values
by space_monk (Chaplain) on Nov 23, 2012 at 13:08 UTC
    Parent beat me to the one line solution, but perhaps a minor mod may be needed; I suspect that the OP may have numbers larger than just 1-6, so perhaps:
    perl -pi -e 's/^(\d+)/chr($1+96)/e' myfile
    A Monk aims to give answers to those who have none, and to learn from those who know more.

      space_monk:

      OK, your solution is a bit better .... at least until you get to "27. This is a really long list!".

      ;^D

      ...roboticus

      When your only tool is a hammer, all problems look like your thumb.

        ... until you get to "27. This is a really long list!".

        Maybe something like (and 'zz' could easily be 'zzz'):

        >perl -wMstrict -e "my @lines = ( '1. This is just a sample.', '2. This is to check', '3. How a set of values', '4. can be replaced by another', '5. set of values and that too', '6. in the most efficient way.', '99. And also handle large numbers.', '999. Oops, too big!', '99 bottles of beer on the wall does not translate!', ); ;; my %xlate; { my @alphas = (undef, 'a' .. 'zz'); @xlate{ 1 .. $#alphas } = @alphas[ 1 .. $#alphas ]; } ;; s{ \A (\d+) (?= [.]) } { exists $xlate{$1} ? $xlate{$1} : (warn(qq{bad '$1' in '$_'}), '??') }xmse for @lines; ;; print qq{$_\n} for @lines; " bad '999' in '999. Oops, too big!' at -e line 1. a. This is just a sample. b. This is to check c. How a set of values d. can be replaced by another e. set of values and that too f. in the most efficient way. cu. And also handle large numbers. ??. Oops, too big! 99 bottles of beer on the wall does not translate!

        Ha ha. I spent an inordinate amount of time trying to make a one-liner solution for arbitrarily large numbers (where it would go to "aa" after "z"). However, it turned out that today is Friday and I can't think that hard.



        When's the last time you used duct tape on a duct? --Larry Wall

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1005246]
help
Chatterbox?
[Corion]: Basically, something that decouples the HTTP parsing (+ determining whether to redirect, etc) from the IO
[Corion]: All clients I'm aware of don't do that but issue all IO themselves

How do I use this? | Other CB clients
Other Users?
Others drinking their drinks and smoking their pipes about the Monastery: (8)
As of 2016-12-07 15:57 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    On a regular basis, I'm most likely to spy upon:













    Results (130 votes). Check out past polls.