[ACCEPTED]-How do I set the floating point precision in Perl?-floating-accuracy
Use Math::BigFloat or bignum:
use Math::BigFloat;
Math::BigFloat->precision(-3);
my $x = Math::BigFloat->new(1.123566);
my $y = Math::BigFloat->new(3.333333);
Or with bignum instead do:
use bignum ( p => -3 );
my $x = 1.123566;
my $y = 3.333333;
Then in both 1 cases:
say $x; # => 1.124
say $y; # => 3.333
say $x + $y; # => 4.457
There is no way to globally change this.
If 5 it is just for display purposes then use 4 sprintf("%.3f", $value);.
For mathematical purposes, use (int(($value * 1000.0) + 0.5) / 1000.0). This 3 would work for positive numbers. You would 2 need to change it to work with negative 1 numbers though.
I wouldn't recommend to use sprintf("%.3f", $value).
Please 2 look at the following example: (6.02*1.25 1 = 7.525)
printf("%.2f", 6.02 * 1.25) = 7.52
printf("%.2f", 7.525) = 7.53
Treat the result as a string and use substr. Like 3 this:
$result = substr($result,0,3);
If you want to do rounding, do it as 2 string too. Just get the next character 1 and decide.
Or you could use the following to truncate 2 whatever comes after the third digit after 1 the decimal point:
if ($val =~ m/([-]?[\d]*\.[\d]{3})/) {
$val = $1;
}
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