cvs commit: perlfaq perlfaq4.pod

cvsuser     03/09/19 23:33:26

  Modified:    .        perlfaq4.pod
  Log:
  Change 21204 by jhi@kosh on 2003/09/13 06:47:23
  
          Subject: [perl #23788] int of a fraction errors
          From: "Boyd, Brooks D" (via RT) <[email protected]>
          Date: 11 Sep 2003 22:38:19 -0000
          Message-ID: <[email protected]>
  
          Add a separate faq entry for int().  (Yes, a bit redundant
          with the existing "why are my numbers broken" entry.)
  
  Affected files ...
  
  ... //depot/perl/pod/perlfaq4.pod#86 edit
  
  Revision  Changes    Path
  1.48      +19 -1     perlfaq/perlfaq4.pod
  
  Index: perlfaq4.pod
  ===================================================================
  RCS file: /cvs/public/perlfaq/perlfaq4.pod,v
  retrieving revision 1.47
  retrieving revision 1.48
  diff -u -w -r1.47 -r1.48
  --- perlfaq4.pod	25 Aug 2003 05:58:04 -0000	1.47
  +++ perlfaq4.pod	20 Sep 2003 06:33:25 -0000	1.48
  @@ -1,6 +1,6 @@
   =head1 NAME
   
  -perlfaq4 - Data Manipulation ($Revision: 1.47 $, $Date: 2003/08/25 05:58:04 $)
  +perlfaq4 - Data Manipulation ($Revision: 1.48 $, $Date: 2003/09/20 06:33:25 $)
   
   =head1 DESCRIPTION
   
  @@ -27,6 +27,24 @@
   	printf "%.2f", 10/3;
   
   	my $number = sprintf "%.2f", 10/3;
  +
  +=head2 Why is int() broken?
  +
  +Your int() is most probably working just fine.  It's the numbers that
  +aren't quite what you think.
  +
  +First, see the above item "Why am I getting long decimals
  +(eg, 19.9499999999999) instead of the numbers I should be getting
  +(eg, 19.95)?".
  +
  +For example, this
  +
  +    print int(0.6/0.2-2), "\n";
  +
  +will in most computers print 0, not 1, because even such simple
  +numbers as 0.6 and 0.2 cannot be presented exactly by floating-point
  +numbers.  What you think in the above as 'three' is really more like
  +2.9999999999999995559.
   
   =head2 Why isn't my octal data interpreted correctly?