PHP: min - Manual

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(2, 3, 1, 6, 7); // 1 echo min(array(2, 4, 5)); // 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(2, 4, 8), array(2, 5, 1)); // array(2, 4, 8) // При указании массива и отдельных чисел, // первый никогда не возвращается, т.к. считается самым большим $val = min('string', array(2, 5, 7), 42); // string ?>

См также max() и count().

min

johnphayes at gmail dot com
02-May-2006 09:26


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 02:16


> 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 09:37


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 06:39


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
12-Jan-2005 05:16


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 07:43


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 02:30


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
18-Jul-2003 08:28


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 09:40


Caution : it seems that min() can return a string : 



min(";",50)=";" (I expected zero)

calin at php9 dot com
30-May-2003 08:19


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 02:36


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 11:47


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 11:36


If one of elements is undefided, min() result is underfinded too