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 !
min
(PHP 4, PHP 5)
min — Encontrar el valor más bajo
Descripción
Si el primer y único parámetro es un array, min() devuelve el valor más bajo de ese array. Si se proporcionan al menos dos parámetros, min() devuelve el menor de estos valores.
Nota:
PHP evaluará un valor string no numérico como 0 si se compara con un integer, pero aún devuelve la cadena si ésta es vista como el valor numérico más bajo. Si varios argumentos se evalúan a 0, min() devolverá el valor de cadena alfanumérica más bajo si se da alguna cadena, o de lo contrario se devuelve un 0 numérico.
Parámetros
-
valores -
Un array que contiene los valores.
-
value1 -
Cualquier valor comparable.
-
value2 -
Cualquier valor comparable.
-
... -
Cualquier valor comparable.
Valores devueltos
min() devuelve el valor numéricamente más bajo de los parámetros.
Ejemplos
Ejemplo #1 Ejemplos de uso de min()
<?php
echo min(2, 3, 1, 6, 7); // 1
echo min(array(2, 4, 5)); // 2
echo min(0, 'hola'); // 0
echo min('hola', 0); // hola
echo min('hola', -1); // -1
// Con varios arrays, min las compara de izquierda a derecha
// así que en nuestro ejemplo: 2 == 2, pero 4 < 5
$val = min(array(2, 4, 8), array(2, 5, 1)); // array(2, 4, 8)
// Si se pasan un array y algo que no sea un array, el array nunca
// es devuelto ya que se considera el valor mayor
$val = min('cadena', array(2, 5, 7), 42); // cadena
?>
Ejemplo #2 Ejemplo de valor NULL/FALSE con min()
<?php
// PHP compara variables como booleanas cuando uno de los operandos es booleano.
var_dump(min(-100,-10, NULL, 10, 100); // NULL - (bool)NULL < (bool)-100 is FALSE < TRUE
var_dump(min(-100,-10, FALSE, 10, 100); // FALSE - (bool)FALSE < (bool)-100 is FALSE < TRUE
?>
add a note
User Contributed Notes 15 notes
Anonymous ¶
8 years ago
php at keith tyler dot com ¶
3 years ago
If NAN is the first argument to min(), the second argument will always be returned.
If NAN is the second argument, NAN will always be returned.
The relationship is the same but inverted for max().
<?php
// \n's skipped for brevity
print max(0,NAN);
print max(NAN,0);
print min(0,NAN);
print min(NAN,0);
?>
Returns:
0
NAN
NAN
0
DO ¶
5 years ago
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 $min;
}
?>
johnphayes at gmail dot com ¶
7 years ago
Regarding boolean parameters in min() and max():
(a) If any of your parameters is boolean, max and min will cast the rest of them to boolean to do the comparison.
(b) true > false
(c) However, max and min will return the actual parameter value that wins the comparison (not the cast).
Here's some test cases to illustrate:
1. max(true,100)=true
2. max(true,0)=true
3. max(100,true)=100
4. max(false,100)=100
5. max(100,false)=100
6. min(true,100)=true
7. min(true,0)=0
8. min(100,true)=100
9. min(false,100)=false
10. min(100,false)=false
11. min(true,false)=false
12. max(true,false)=true
alx5000 at walla dot com ¶
9 years ago
If you want min to return zero (0) when comparing to a string, try this:
<?php
min(3,4,";"); // ";"
min(0,min(3,4,";")) // 0
?>
harmor ¶
6 years ago
A way to bound a integer between two values is:
function bound($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
nonick AT 8027 DOT org ¶
10 years ago
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.
Err ¶
4 years ago
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
?>
hava82 at gmail dot com ¶
2 years ago
Here is function can find min by array key
<?php
function min_by_key($arr, $key){
$min = array();
foreach ($arr as $val) {
if (!isset($val[$key]) and is_array($val)) {
$min2 = min_by_key($val, $key);
$min[$min2] = 1;
} elseif (!isset($val[$key]) and !is_array($val)) {
return false;
} elseif (isset($val[$key])) {
$min[$val[$key]] = 1;
}
}
return min( array_keys($min) );
}
?>
Teelevision ¶
6 months ago
A function that returns the lowest integer that is not 0.
<?php
/* like min(), but casts to int and ignores 0 */
function min_not_null(Array $values) {
return min(array_diff(array_map('intval', $values), array(0)));
}
?>
dave at dtracorp dot com ¶
7 years ago
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;
}
matt at borjawebs dot com ¶
3 years ago
A condensed version (and possible application) of returning an array of array keys containing the same minimum value:
<?php
// data
$min_keys = array();
$player_score_totals = array(
'player1' => 300,
'player2' => 301,
'player3' => 302,
'player4' => 301,
...
);
// search for array keys with min() value
foreach($player_score_totals as $playerid => $score)
if($score == min($player_score_totals)) array_push($min_keys, $playerid);
print_r($min_keys);
?>
piotr_sobolewski at o2 dot nospampleasenono dot pl ¶
6 years ago
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'));
steffen at morkland dot com ¶
8 years ago
> 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 ===
browne at bee why you dot ee dee you ¶
10 years ago
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);
