Beefy Boxes and Bandwidth Generously Provided by pair Networks
Think about Loose Coupling
 
PerlMonks  

How do I add commas to a number?

( #2145=categorized question: print w/ replies, xml ) Need Help??
Contributed by vroom on Jan 18, 2000 at 22:54 UTC
Q&A  > numbers


Answer: How do I add commas to a number?
contributed by Fastolfe

See perlfaq5: How can I output my numbers with commas added?. In addition, that FAQ apparently used to include the following, contributed by Andrew Johnson, as well:

sub commify { my $input = shift; $input = reverse $input; $input =~ s/(\d\d\d)(?=\d)(?!\d*\.)/$1,/g; return reverse $input; }
Answer: How do I add commas to a number?
contributed by Roy Johnson

A lookaround method that will work on any numbers embedded in a string (but will not commify after a decimal point):

sub commify { local $_ = shift; s{(?<!\d|\.)(\d{4,})} {my $n = $1; $n=~s/(?<=.)(?=(?:.{3})+$)/,/g; $n; }eg; return $_; }
If you prefer the FAQ rule of only working on things that begin with digits or -,
sub commify { local $_ = shift; s{(?:(?<=^)|(?<=^-))(\d{4,})} {my $n = $1; $n=~s/(?<=.)(?=(?:.{3})+$)/,/g; $n; }e; return $_; }
This one does a single pattern match and then uses substr() to insert the commas:
sub commify { local $_ = shift; if (/^-?(\d{4,})/g) { for (my $p=$+[1]; $p>$-[1]; $p-=3) { substr($_,$p,0) = ',' } } return $_; }

Please (register and) log in if you wish to add an answer



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • Outside of code tags, you may need to use entities for some characters:
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others exploiting the Monastery: (7)
    As of 2014-08-30 00:27 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      The best computer themed movie is:











      Results (289 votes), past polls