Hey ho, esteemed monks!

I am parsing through a csv file and converting a bunch of spreads from percentages to basis points (and stripping off the percent sign). The number of digits in any given field can vary. I want the output to have the same amount of accuracy as the input. However, a simple print of the value seems to round in an unacceptable fashion. The code below is an excerpt, so if a variable is undeclared or undefined, please ignore unless relevant: 

use strict;#etc,
my $parser = Text::CSV::Simple->new();
$parser->field_map(@fm);
my @data = $parser->read_file($tf);
my $ln   = 0;
open( my $cfh, '>', $cf ) || die "Can't open $cf: $!";
foreach my $row (@data) {
  ++$ln;
  if ( $ln > 1 ) {
  if ( my $date = ParseDate( $row->{Date} ) ) {
    $row->{Date} = UnixDate( $date, "%m/%d/%Y" );
  }
  else {
    print "ERROR: $row->{Date} not a date!";
  }
  foreach my $f ( keys %$row ) {
    if ( $f =~ m/^Spread\d\d?[my]$/ &&  $row->{$f} ne q{} ){
      print "Fixing a percentage ($f) --now $row->{$f}";
      $row->{$f} =~ s/^($RE{num}{decimal})%$/$1*100/e
                        || die "Pattern match failed!";
      print "--now $row->{$f}";
    }
    if ( index( $row->{$f}, ',' ) != -1 ) {
      $row->{$f} = qq{"$row->{$f}"};
    }
  } ## end foreach my $f ( keys %$row )
  } ## end if ( $ln > 1 )
  print {$cfh} join( ',', @{$row}{@fm} );
} ## end foreach my $row (@data)
close $cfh || die "Can't close $cf: $!";

[download]
Here's some sample output: 
Fixing a percentage (Spread3y) --now 0.781063003540039%
--now 78.1063003540039
Fixing a percentage (Spread5y) --now 2.25%
--now 225
Fixing a percentage (Spread3y) --now 1.455%
--now 145.5
Fixing a percentage (Spread5y) --now 4.9%
--now 490
Fixing a percentage (Spread5y) --now 0.79%
--now 79
Fixing a percentage (Recovery) --now 75%
--now 7500
Fixing a percentage (Spread5y) --now 1.15%
--now 115
Fixing a percentage (Spread2y) --now 0.45999999999999996%
--now 46
Fixing a percentage (Spread4y) --now 0.9199999999999999%
--now 92
Fixing a percentage (Spread1y) --now 0.22999999999999998%
--now 23
Fixing a percentage (Spread7y) --now 1.3%
--now 130

[download]
Not what I am looking for! After reading My floating point comparison does not work. Why ?, I see that sprintf is probably the way to go, but can I make it dynamic so that I don't end up with values like 490.00000000000000 in the munged file?

As always, if you see other areas of the snippet where I could improve the logic/efficiency, feel free to comment!

TIA!

EDIT:Changed title to accuracy, to reflect nomenclature per Math::BigFloat; accuracy means total number of digits, while precision (which I call "significant (?:digits|figures)") means number of digits after the decimal.

I like computer programming because it's like Legos for the mind.

In reply to Maintain accuracy of floating point numbers in simple arithmetic operation by OfficeLinebacker

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