.\" Automatically generated by Pod::Man 4.14 (Pod::Simple 3.40) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" ======================================================================== .\" .IX Title "Round 3pm" .TH Round 3pm "2020-12-28" "perl v5.32.0" "User Contributed Perl Documentation" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" Math::Round \- Perl extension for rounding numbers .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& 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 below .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" \&\fBMath::Round\fR supplies functions that will round numbers in different ways. The functions \fBround\fR and \fBnearest\fR are exported by default; others are available as described below. \*(L"use ... qw(:all)\*(R" exports all functions. .SH "FUNCTIONS" .IX Header "FUNCTIONS" .IP "\fBround\fR \s-1LIST\s0" 2 .IX Item "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 \&\*(L"to infinity\*(R"; i.e., positive values are rounded up (e.g., 2.5 becomes 3) and negative values down (e.g., \-2.5 becomes \-3). .Sp Starting in Perl 5.22, the \s-1POSIX\s0 module by default exports all functions, including one named \*(L"round\*(R". If you use both \s-1POSIX\s0 and this module, exercise due caution. .IP "\fBround_even\fR \s-1LIST\s0" 2 .IX Item "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. .IP "\fBround_odd\fR \s-1LIST\s0" 2 .IX Item "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. .IP "\fBround_rand\fR \s-1LIST\s0" 2 .IX Item "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. .IP "\fBnearest\fR \s-1TARGET, LIST\s0" 2 .IX Item "nearest TARGET, LIST" Rounds the number(s) to the nearest multiple of the target value. \&\s-1TARGET\s0 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: .Sp .Vb 6 \& 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) \-50 .Ve .IP "\fBnearest_ceil\fR \s-1TARGET, LIST\s0" 2 .IX Item "nearest_ceil TARGET, LIST" Rounds the number(s) to the nearest multiple of the target value. \&\s-1TARGET\s0 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: .Sp .Vb 3 \& nearest_ceil(10, 44) yields 40 \& nearest_ceil(10, 45) 50 \& nearest_ceil(10, \-45) \-40 .Ve .IP "\fBnearest_floor\fR \s-1TARGET, LIST\s0" 2 .IX Item "nearest_floor TARGET, LIST" Rounds the number(s) to the nearest multiple of the target value. \&\s-1TARGET\s0 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: .Sp .Vb 3 \& nearest_floor(10, 44) yields 40 \& nearest_floor(10, 45) 40 \& nearest_floor(10, \-45) \-50 .Ve .IP "\fBnearest_rand\fR \s-1TARGET, LIST\s0" 2 .IX Item "nearest_rand TARGET, LIST" Rounds the number(s) to the nearest multiple of the target value. \&\s-1TARGET\s0 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, \f(CW\*(C`nearest(10, 45)\*(C'\fR will yield 40 half the time and 50 half the time. .IP "\fBnlowmult\fR \s-1TARGET, LIST\s0" 2 .IX Item "nlowmult TARGET, LIST" Returns the next lower multiple of the number(s) in \s-1LIST. TARGET\s0 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 \s-1LIST\s0 that are algebraically lower. For example: .Sp .Vb 5 \& nlowmult(10, 44) yields 40 \& nlowmult(10, 46) 40 \& nlowmult(25, 328) 325 \& nlowmult(.1, 4.567) 4.5 \& nlowmult(10, \-41) \-50 .Ve .IP "\fBnhimult\fR \s-1TARGET, LIST\s0" 2 .IX Item "nhimult TARGET, LIST" Returns the next higher multiple of the number(s) in \s-1LIST. TARGET\s0 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 \s-1LIST\s0 that are algebraically higher. For example: .Sp .Vb 5 \& nhimult(10, 44) yields 50 \& nhimult(10, 46) 50 \& nhimult(25, 328) 350 \& nhimult(.1, 4.512) 4.6 \& nhimult(10, \-49) \-40 .Ve .SH "VARIABLE" .IX Header "VARIABLE" The variable \fB\f(CB$Math::Round::half\fB\fR 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. .SH "STANDARD FLOATING-POINT DISCLAIMER" .IX Header "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). .PP 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. .SH "AUTHOR" .IX Header "AUTHOR" Math::Round was written by Geoffrey Rommel in October 2000.