Math::Round - Perl extension for rounding numbers
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
Math::Round supplies functions that will round numbers in different ways. The functions round and nearest are exported by default; others are available as described below. "use ... qw(:all)" exports all functions.
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).
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.
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.
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.
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) -50
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) -40
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) -50
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.
nearest(10, 45)
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) -50
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) -40
Floating-point numbers are, of course, a rational subset of the real numbers, so calculations with them are not always exact. In order to avoid surprises because of this, these routines use a value for one-half that is very 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. Thus, numbers that are supposed to be halfway between two others may be stored in a slightly different way and thus behave surprisingly.
Math::Round was written by Geoffrey Rommel <GROMMEL@cpan.org> in October 2000.
To install Math::Round, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Math::Round
CPAN shell
perl -MCPAN -e shell install Math::Round
For more information on module installation, please visit the detailed CPAN module installation guide.