There are may ways to do it, for example, if you are familiar with C, you might like to use printf() or sprintf().

I will show you another way, simply using string formatting : 

  my $number = 10.8766756;
  my $string = $number . ""; # force $number into a string
  $string =~ s/(\.\d)\d*/\1/; # if $string has one (or more) decimal
  # figures, replace them all by the first decimal figure

[download]

Another one is the purely mathematical method, which might (or might not) work, depending on the size of your numbers (notice that arithmetic with floating point numbers is not always exact) :
The int() function returns the integer part of a number, so we simply calculate 

  $string = int( $number * 100 ) / 100;

[download]
which will also give you 10.8, but note that the number is not rounded but truncated to 0, as the int documentation will tell you.

In reply to Methods to format a number by Corion
in thread Numbers.... by Anonymous Monk

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