Beefy Boxes and Bandwidth Generously Provided by pair Networks
We don't bite newbies here... much
 
PerlMonks  

Re: One liner to subtract by 2

by choroba (Chancellor)
on Jul 24, 2013 at 14:05 UTC ( #1046122=note: print w/replies, xml ) Need Help??


in reply to One liner to subtract by 2

You can use the /e switch of the substitution operator:
perl -pe 's/([0-9]{10})$/sprintf "%010d",$1-2/e'

Update: I am not sure how to search for the line, though, because you did not give any information on how these lines are structured. Adding that to the one-liner is easy, e.g. let's pretend we want to process lines beginning with 0TONY:

perl -pe 's/([0-9]{10})$/sprintf "%010d",$1-2/e if /^0TONY/'

Update 2: sprintf added. Thanks derby.

لսႽ ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

Replies are listed 'Best First'.
Re^2: One liner to subtract by 2
by derby (Abbot) on Jul 24, 2013 at 14:08 UTC

    You'll lose leading zeros with that.

    -derby

    update: so perl -pe 's/([0-9]{10})$/sprintf("%010d", $1-2)/e'

      Thanks, fixed.
      لսႽ ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

        Thanks Guys

        the header is on the first line of my file so I'm doing the following

        perl -pe 's/(0-9{10})$/sprintf("%010d", $1-2)/e if $. ==1' TONYFILE.DAT

        for some reason it's not changing the count...it's still 496

        any idea what i'm missing here?

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://1046122]
help
Chatterbox?
[choroba]: Morning!
[Corion]: Hi choroba, Discipulus!
[Corion]: Yesterday I've been mulling over how to best generate HTTP requests from permutations of values but I haven't found a nice API for passing in the "template" of the HTTP request yet. I guess I'll have to do a SoPW for that
[Corion]: The API itself will basically be my $iter = generate_http_requ ests(method => 'GET', url => '/settings/:name', headers => ???, get_params => ['foo','bar']), but I'm not sure how to parametrize values in the headers and how to specify lists of ...
[choroba]: On the other hand, lots of options to receive the requests :-)
[Corion]: ... values to be used. For example, I think for headers, one would want to have various kinds of Content-Encoding headers, but for the get_parameters one would have various kinds of Bobby Tables
[choroba]: What about [metadoc:// Algorithm::Loops]?
[Corion]: choroba: Yeah, but handing off the request to Dancer,Plack, Mojolicious,LWP is easy once I have the data filled into some structure ;))
[choroba]: Algorithm::Loops

How do I use this? | Other CB clients
Other Users?
Others making s'mores by the fire in the courtyard of the Monastery: (5)
As of 2017-01-17 08:12 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?
    Do you watch meteor showers?




    Results (152 votes). Check out past polls.