Math::Round(3)
💖 Math::Round(3) — the Perl page that makes numbers behave 💖
okay so bestie, welcome to Math::Round, a User Contributed Perl Documentation page, and honestly it's giving "tiny module, huge personality." It's a Perl extension for rounding numbers, and once you get it you're gonna be obsessed. Let's go ✨
🌸 NAME 🌸
Math::Round — Perl extension for rounding numbers. That's it, that's the whole vibe. Numbers go in, rounded numbers come out, chaos is managed. 🎀
🦋 SYNOPSIS 🦋
use Math::Round qw(...those desired... or :all);
$rounded = round($scalar);
@rounded = round(LIST...);
$rounded = nearest($target, $scalar);
@rounded = nearest($target, LIST...);
# and other functions as described belowso like, you pull in the functions you want (literally just say :all if you're feeling greedy, no cap), then you round stuff. scalars get rounded, lists get rounded, everyone eats. 💅
✨ DESCRIPTION ✨
Math::Round supplies functions that will round numbers in different ways. Different flavours of rounding, if you will — main character energy for every math emergency.
The functions round and nearest are exported by default; others are available as described below. And use ... qw(:all) exports all functions — boom, full set unlocked 👑
🔥 FUNCTIONS 🔥
⭐ round LIST
Rounds the number(s) to the nearest integer. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two integers are rounded "to infinity"; i.e., positive values are rounded up (e.g., 2.5 becomes 3) and negative values down (e.g., -2.5 becomes -3). So it just keeps going in whichever direction infinity lives, no hesitation 💫
🚨 real talk: Starting in Perl 5.22, thePOSIXmodule by default exports all functions, including one namedround. If you use bothPOSIXand this module, exercise due caution. Tworounds walking into the same namespace is not the slay you think it is 😭
⭐ round_even LIST
Rounds the number(s) to the nearest integer. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two integers are rounded to the nearest even number; e.g., 2.5 becomes 2, 3.5 becomes 4, and -2.5 becomes -2. Even numbers stay winning, periodt 🫶
⭐ round_odd LIST
Rounds the number(s) to the nearest integer. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two integers are rounded to the nearest odd number; e.g., 3.5 becomes 3, 4.5 becomes 5, and -3.5 becomes -3. Odd numbers get their moment too, we love balance 🌈
⭐ round_rand LIST
Rounds the number(s) to the nearest integer. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two integers are rounded up or down in a random fashion. For example, in a large number of trials, 2.5 will become 2 half the time and 3 half the time. literally a coin flip, so chaotic, so fun 🙈
⭐ nearest TARGET, LIST
Rounds the number(s) to the nearest multiple of the target value. TARGET must be positive. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two multiples of the target will be rounded to infinity. For example:
nearest(10, 44) yields 40
nearest(10, 46) 50
nearest(10, 45) 50
nearest(25, 328) 325
nearest(.1, 4.567) 4.6
nearest(10, -45) -50see how 45 went up to 50 and -45 went down to -50? infinity direction, every time, iconic behavior 💀
⭐ nearest_ceil TARGET, LIST
Rounds the number(s) to the nearest multiple of the target value. TARGET must be positive. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two multiples of the target will be rounded to the ceiling, i.e. the next algebraically higher multiple. For example:
nearest_ceil(10, 44) yields 40
nearest_ceil(10, 45) 50
nearest_ceil(10, -45) -40ceiling means up, always up, even when the number is negative and "up" is confusing — algebraically higher, bestie, that's the rule 🦋
⭐ nearest_floor TARGET, LIST
Rounds the number(s) to the nearest multiple of the target value. TARGET must be positive. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two multiples of the target will be rounded to the floor, i.e. the next algebraically lower multiple. For example:
nearest_floor(10, 44) yields 40
nearest_floor(10, 45) 40
nearest_floor(10, -45) -50opposite energy from nearest_ceil, down we go, algebraically lower, no notes ✨
⭐ nearest_rand TARGET, LIST
Rounds the number(s) to the nearest multiple of the target value. TARGET must be positive. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are halfway between two multiples of the target will be rounded up or down in a random fashion. For example, in a large number of trials, nearest(10, 45) will yield 40 half the time and 50 half the time. yes, the manpage literally says nearest(10, 45) in the example for nearest_rand — that's what's written, we're keeping it exactly as-is, no edits 🎀
⭐ nlowmult TARGET, LIST
Returns the next lower multiple of the number(s) in LIST. TARGET must be positive. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are between two multiples of the target will be adjusted to the nearest multiples of LIST that are algebraically lower. For example:
nlowmult(10, 44) yields 40
nlowmult(10, 46) 40
nlowmult(25, 328) 325
nlowmult(.1, 4.567) 4.5
nlowmult(10, -41) -50lowkey just always downward, even when you'd expect it to sneak upward 💜
⭐ nhimult TARGET, LIST
Returns the next higher multiple of the number(s) in LIST. TARGET must be positive. In scalar context, returns a single value; in list context, returns a list of values.
Numbers that are between two multiples of the target will be adjusted to the nearest multiples of LIST that are algebraically higher. For example:
nhimult(10, 44) yields 50
nhimult(10, 46) 50
nhimult(25, 328) 350
nhimult(.1, 4.512) 4.6
nhimult(10, -49) -40the mirror twin of nlowmult, always reaching up, main character upward momentum 🔥
🧚 VARIABLE 🧚
The variable $Math::Round::half is used by most routines in this module. Its value is very slightly larger than 0.5, for reasons explained below.
If you find that your application does not deliver the expected results, you may reset this variable at will. it's your variable, bestie, you hold the power 💅
🌊 STANDARD FLOATING-POINT DISCLAIMER 🌊
Floating-point numbers are, of course, a rational subset of the real numbers, so calculations with them are not always exact. Numbers that are supposed to be halfway between two others may surprise you; for instance, 0.85 may not be exactly halfway between 0.8 and 0.9, and (0.75 - 0.7) may not be the same as (0.85 - 0.8).
😭 floating point said "I contain multitudes" and honestly it meant it.
In order to give more predictable results, these routines use a value for one-half that is slightly larger than 0.5. Nevertheless, if the numbers to be rounded are stored as floating-point, they will be subject as usual to the mercies of your hardware, your C compiler, etc.
so like — we did our part, but your hardware and your C compiler are co-authors of your destiny now. no cap 🫶
👑 AUTHOR 👑
Math::Round was written by Geoffrey Rommel <GROMMEL@cpan.org> in October 2000. legend behavior, honestly 🌟
🎀 COPYRIGHT AND LICENSE 🎀
This software is copyright (c) 2000 by Geoffrey Rommel <grommel@cpan.org>.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. free software, slay 💖
and that's the page!! compiled as perl v5.42.0, dated 2024-03-08, filed under Math::Round(3) — go forth and round responsibly, bestie 🦋✨💅
📦 where this page comes from
- opensuse-leap 16.0: perl-Math-Round 0.80.0-bp160.1.11 · Artistic-1.0 OR GPL-1.0-or-later
- 💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash-1017 on : a language model's rewrite of the original, under its terms