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min

(PHP 4, PHP 5)

minНаходит наименьшее значение

Описание

mixed min ( number $arg1 , number $arg2 [, number $... ] )
mixed min ( array $numbers )

Возвращает наименьшее из предложенных чисел.

Если в качестве аргументов передан только один - массив чисел, min() возвращает наименьшее из них. Если первый аргумент - integer или float, то обязательно должен быть хотя бы ещё один. В этом случае функция вернёт наименьшее из них. Можно сравнивать неограниченное количество чисел.

Замечание: PHP считает строку, которую не удалось преобразовать в число, как 0, но вернёт саму строку, в случае, если все остальные числа положительные. Если указано несколько элементов, эквивалентных 0, min() вернёт первый из них (самый левый).

Пример #1 Примеры использования min()

<?php
echo min(23167);  // 1
echo min(array(245)); // 2

echo min(0'hello');     // 0
echo min('hello'0);     // hello
echo min('hello', -1);    // -1

// При указании нескольких массивов, они сравниваются полностью
// в нашем примере: 2 == 2, но 4 < 5
$val min(array(248), array(251)); // array(2, 4, 8)

// При указании массива и отдельных чисел, 
// первый никогда не возвращается, т.к. считается самым большим
$val min('string', array(257), 42);   // string
?>

См также max() и count().


User Contributed Notes
min
Err
05-Oct-2009 11:32
When using a variable with an array that has a list of numbers, put just the variable in min(). Don't use integer index's. Seems pretty straight forward now, but I wasn't used to just putting down the variable for an array in functions.

<?php
  $list
= array(9,5,4,6,2,7);
  echo
min($list); // display 2
?>
andrew dot j dot dodson at gmail
18-Dec-2008 05:10
min/max works with yyyy-mm-dd dates, e.g.

<?php

$a
= array(   '2008-10-01',    '2008-12-01'  );

print
min($a); //  '2008-10-01'
print max($a); //  '2008-12-01'

?>

Which is a unexpected since at the top of this page it says.
"PHP will evaluate a non-numeric string as 0"

And if we cast it as an int then we get the year

<?php
print (int)"2008-01-12"; // 2008
?>
ksours at internetbrands dot com
02-Dec-2008 12:07
PHP_INT_MAX is the MAXINT equivalent
mlester at ndsuk dot com
12-Nov-2008 03:59
I have found a very useful trick to help get round the problem of setting a variable to max int when finding a min i.e.

<?php
$val
= 10;
$min = 100000 // This is unpleasant and I couldn't find a equivalent to the C++ MAXINT
if ($val < $min)
{
 
$min = $val;
}
?>

try this ...

<?php
$dataSet
= Array(7, 8, 9, -1, -100, 0, 1, 2, 3, 5, 6);
$min = true;
$max = true;
           
foreach (
$dataSet as $data )
{
  echo(
"data = $data");
 
$min = min($data, $min);
 
$max = max($data, $max);
}
           
echo(
"min = $min");
echo(
"max = $max");
?>

$max can be set to anything e.g. "infinity", but the same trick doesn't work with min, however true does work (false doesn't). Not sure why though.

The above code even works with a data set like this...
<?php $dataSet = Array("0.5", 1, 2, "3", "-1", "5"); ?>

but min doesn't like null or negative float e.g. "-1.2" and "" can give some odd results too.
DO
03-Jul-2008 10:23
I've modified the bugfree min-version to ignore NULL values (else it returns 0).

<?php
function min_mod () {
 
$args = func_get_args();
 
  if (!
count($args[0])) return false;
  else {
   
$min = false;
    foreach (
$args[0] AS $value) {
      if (
is_numeric($value)) {
       
$curval = floatval($value);
        if (
$curval < $min || $min === false) $min = $curval;
      }
    }
  }
 
  return
$min;  
}
?>
harmor
21-Feb-2008 05:58
A way to bound a integer between two values is:

function bound($x, $min, $max)
{
     return min(max($x, $min), $max);
}

which is the same as:

$tmp = $x;
if($tmp < $min)
{
    $tmp = $min;
}
if($tmp > $max)
{
     $tmp = $max;
}
$y = $tmp;

So if you wanted to bound an integer between 1 and 12 for example:

Input:
$x = 0;
echo bound(0, 1, 12).'<br />';
$x = 1;
echo bound($x, 1, 12).'<br />';
$x = 6;
echo bound($x, 1, 12).'<br />';
$x = 12;
echo bound($x, 1, 12).'<br />';
$x = 13;
echo bound($x, 1, 12).'<br />';

Output:
1
1
6
12
12
johngreenbury at australianescapes dot com dot au
30-Jan-2008 01:43
You will get an "Wrong parameter count" error (PHP 4 and possibly 5) if your array looks like the following:

min(115.23,432.11,0.00,45.76)

The 0.00 creates the error. Convert the 0.00 to a high number such as 10000000000.00 or remove it from the array before running the min() function.
piotr_sobolewski at o2 dot nospampleasenono dot pl
07-Nov-2007 04:11
Be very careful when your array contains both strings and numbers. This code works strange (even though explainable) way:
var_dump(max('25.1.1', '222', '99'));
var_dump(max('2.1.1', '222', '99'));
dave at dtracorp dot com
14-Aug-2006 03:30
empty strings '' will also return false or 0, so if you have something like

$test = array('', 1, 5, 8, 44, 22);

'' will be returned as the lowest value

if you only want to get the lowest number, you'll have to resort to the old fashioned loop

// default minimum value
$minVal = 100;
foreach ($test as $value) {
if (is_numeric($value) && $value < $minVal) {
$minVal = $value;
}
johnphayes at gmail dot com
02-May-2006 04:26
Regarding boolean parameters in min() and max():

(a) If any of your parameters is boolean, max and min will cast the rest of them to boolean to do the comparison.
(b) true > false
(c) However, max and min will return the actual parameter value that wins the comparison (not the cast).

Here's some test cases to illustrate:

1.  max(true,100)=true
2.  max(true,0)=true
3.  max(100,true)=100
4.  max(false,100)=100
5.  max(100,false)=100
6.  min(true,100)=true
7.  min(true,0)=0
8.  min(100,true)=100
9.  min(false,100)=false
10. min(100,false)=false
11. min(true,false)=false
12. max(true,false)=true
steffen at morkland dot com
16-Mar-2006 10:16
> NEVER EVER use this function with boolean variables !!!
> Or you'll get something like this: min(true, 1, -2) == true;

> Just because of:
> min(true, 1, -2) == min(min(true,1), -2) == min(true, -2) == true;

It is possible to use it with booleans, there is is just one thing, which you need to keep in mind, when evaluating using the non strict comparison (==) anyting that is not bool false, 0 or NULL is consideret true eg.:
(5 == true) = true;
(0 == true) = false;
true is also actually anything else then 0, false and null. However when true is converted to a string or interger true == 1, therefore when sorting true = 1. But if true is the maximum number bool true is returned. so to be sure, if you only want to match if true is the max number remember to use the strict comparison operater ===
31-Jan-2006 05:37
NEVER EVER use this function with boolean variables !!!
Or you'll get something like this: min(true, 1, -2) == true;

Just because of:
min(true, 1, -2) == min(min(true,1), -2) == min(true, -2) == true;

You are warned !
DASPRiD - d [AT] sprid [DOT] de
06-Jul-2005 01:39
Here is my slightly modified version of the bugfree min-version. Now the max() function is no longer used in the modification and overall it's fasten up. Would be nice to get some feedback.

<?php
function min_mod () {
 
$args = func_get_args();
 
  if (!
count($args)) return false;
  else {
   
$min = false;
    foreach (
$args AS $value) {
     
$curval = floatval($value);
      if (
$curval < $min || $min === false) $min = $curval;
    }
  }
 
  return
$min;   
}
?>
alx5000 at walla dot com
13-Jan-2005 01:16
If you want min to return zero (0) when comparing to a string, try this:

<?php
min
(3,4,";");  // ";"
min(0,min(3,4,";")) // 0
?>
nonick AT 8027 DOT org
24-Jan-2004 03:43
I tested this with max(), but I suppose it applies to min() too: If you are working with numbers, then you can use:
 
    $a = ($b < $c) ? $b : $c;
 
 which is somewhat faster (roughly 16%) than
 
    $a = min($b, $c);
 
 I tested this on several loops using integers and floats, over 1 million iterations.
 
 I'm running PHP 4.3.1 as a module for Apache 1.3.27.
browne at bee why you dot ee dee you
16-Dec-2003 10:30
min() can be used to cap values at a specific value. For instance, if you're grading papers and someone has some extra credit, but  that shouldn't make it to the final score:

$pts_possible = 50;
$score = 55;

// Percent will equal 1 if $score/$pts_possible is greater than 1
$percent = min($score/$pts_possible,1);
kieran at mgpenguin dot net
19-Jul-2003 03:28
Further modifications to the minnum function above.. This is for a project where I had to grab an entire column out of a database consisting of values that might be string, might be string representations of numbers (floating point or integer) or might be NULL, and find the minimum NUMERIC value:

function minnum($numarray){
    //dont use min(), it contains a bug!
    $min=0;
    if ( ! is_array($numarray) ) $numarray = func_get_args();
    if(is_array($numarray)==true){
        $min=max($numarray);
        for($z=0;$z<count($numarray);$z++){
            $curval=floatval($numarray[$z]);
            if(($curval != 0) && ($curval < $min)){
                $min=$curval;
            }
        }
    }
    return $min;
}

Gets the floating point value of each entry and uses this to check whether it's actually a number before checking whether it's the minimum or not. Also contains modifications noted above to use it as a drop in replacement for min - ie multiple values passed.
Merome at wanadoo dot fr
05-Jul-2003 04:40
Caution : it seems that min() can return a string :

min(";",50)=";" (I expected zero)
calin at php9 dot com
30-May-2003 03:19
if you have an array like this

$arSrc[0]=14;
$arSrc[1]=16;
$arSrc[2]=13;
$arSrc[3]=17;

then in order to get the min element and its position in the array you can do:

$iMinValue = min($arSrc);
$arFlip = array_flip($arSrc);
$iMinPosition = $arFlip[$iMinValue];

echo
 '<br />min_value=',
 $iMinValue,
 '<br />min_position=',
 $iMinPosition
;

this example works for also for an associative array; of course with numeric values
08-Jul-2002 09:36
Re: above example - for a proper drop in replacement for the above, insert

if ( ! is_array($numarray) )
   $numarray = func_get_args();

after
   $min=0;

(For PHP3, check
if (intval(PHP_VERSION) >= 4 && ! is_array($numarray))
   $numarray = func_get_args();
)
kevin at pricetrak dot com
08-Apr-2002 06:47
The 'undefined' behaviour can bit you badly. I would expect min(undefined, -1000) to return -1000. Not so.
nak2 at mail2000 dot ru
14-Mar-2002 07:36
If one of elements is undefided, min() result is underfinded too
 

 
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