In this case sprintf is your friend (and coming from a C background an asset). It might slow you down somehow but if you throw in $val= sprintf( "%f6.2", $val); before using $val, you will get back the proper precision.

Here is an example:

 #!/usr/bin/perl -w
use strict;

my @rows=<DATA>;

my $val=0;
   for (@rows) {
     chomp;
     if (/([\d.]+)/) {
       $val += $1;
       $val= sprintf( "%6.2f", $val);
       warn "Added $1 from $_ and set it to $val\n";
     }
   }

__DATA__
we get to $6257.65
now we add $33.4099999999999999
we add $37.24

[download]

outputs:

Added 6257.65 from we get to $6257.65 and set it to 6257.65
Added 33.4099999999999999 from now we add $33.4099999999999999 and set it to 6291.06
Added 37.24 from we add $37.24 and set it to 6328.30

In reply to Re: Unwanted implicit conversion to float by mirod
in thread Unwanted implicit conversion to float by turnstep

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • 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, details, 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, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            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.