|laziness, impatience, and hubris|
Does perl have a round function? What about ceil() and floor()? Trig functions?by faq_monk (Initiate)
|on Oct 08, 1999 at 00:20 UTC||Need Help??|
Current Perl documentation can be found at perldoc.perl.org.
Here is our local, out-dated (pre-5.6) version:
printf("%.3f", 3.1415926535); # prints 3.142
POSIX module (part of the standard perl distribution) implements
use POSIX; $ceil = ceil(3.5); # 4 $floor = floor(3.5); # 3
In 5.000 to 5.003 Perls, trigonometry was done in the Math::Complex module. With 5.004, the Math::Trig module (part of the standard perl distribution) implements the trigonometric functions. Internally it uses the Math::Complex module and some functions can break out from the real axis into the complex plane, for example the inverse sine of 2.
Rounding in financial applications can have serious implications, and the rounding method used should be specified precisely. In these cases, it probably pays not to trust whichever system rounding is being used by Perl, but to instead implement the rounding function you need yourself.