min() (and max()) on DateTime objects compares them like dates (with timezone info) and returns DateTime object.
<?php
$dt1 = new DateTime('2014-05-07 18:53', new DateTimeZone('Europe/Kiev'));
$dt2 = new DateTime('2014-05-07 16:53', new DateTimeZone('UTC'));
echo max($dt1,$dt2)->format(DateTime::RFC3339) . PHP_EOL; // 2014-05-07T16:53:00+00:00
echo min($dt1,$dt2)->format(DateTime::RFC3339) . PHP_EOL; // 2014-05-07T18:53:00+03:00
?>
It works at least 5.3.3-7+squeeze17
min
(PHP 4, PHP 5, PHP 7)
min — Find lowest value
Descrierea
Alternative signature (not supported with named arguments):
If the first and only parameter is an array, min() returns the lowest value in that array. If at least two parameters are provided, min() returns the smallest of these values.
Notă:
Values of different types will be compared using the standard comparison rules. For instance, a non-numeric string will be compared to an int as though it were
0, but multiple non-numeric string values will be compared alphanumerically. The actual value returned will be of the original type with no conversion applied.
Precauţie
Be careful when passing arguments of different types because min() can produce unpredictable results.
Parametri
-
value -
Any comparable value.
-
values -
Any comparable values.
-
value_array -
An array containing the values.
Valorile întoarse
min() returns the parameter value considered "lowest" according to standard
comparisons. If multiple values of different types evaluate as equal (e.g. 0
and 'abc') the first provided to the function will be returned.
If an empty array is passed, then false will be returned and an
E_WARNING error will be emitted.
Exemple
Example #1 Example uses of min()
<?php
echo min(2, 3, 1, 6, 7); // 1
echo min(array(2, 4, 5)); // 2
// The string 'hello' when compared to an int is treated as 0
// Since the two values are equal, the order they are provided determines the result
echo min(0, 'hello'); // 0
echo min('hello', 0); // hello
// Here we are comparing -1 < 0, so -1 is the lowest value
echo min('hello', -1); // -1
// With multiple arrays of different lengths, min returns the shortest
$val = min(array(2, 2, 2), array(1, 1, 1, 1)); // array(2, 2, 2)
// Multiple arrays of the same length are compared from left to right
// so in our example: 2 == 2, but 4 < 5
$val = min(array(2, 4, 8), array(2, 5, 1)); // array(2, 4, 8)
// If both an array and non-array are given, the array is never returned
// as comparisons treat arrays as greater than any other value
$val = min('string', array(2, 5, 7), 42); // string
// If one argument is NULL or a boolean, it will be compared against
// other values using the rules FALSE < TRUE and NULL == FALSE regardless of the
// other types involved
// In the below examples, both -10 and 10 are treated as TRUE in the comparison
$val = min(-10, FALSE, 10); // FALSE
$val = min(-10, NULL, 10); // NULL
// 0, on the other hand, is treated as FALSE, so is "lower than" TRUE
$val = min(0, TRUE); // 0
?>
add a note
User Contributed Notes 17 notes
volch5 at gmail dot com ¶
10 years ago
Anonymous ¶
18 years ago
NEVER EVER use this function with boolean variables !!!
Or you'll get something like this: min(true, 1, -2) == true;
Just because of:
min(true, 1, -2) == min(min(true,1), -2) == min(true, -2) == true;
You are warned !
harmor ¶
16 years ago
A way to bound a integer between two values is:
function bound($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
steffen at morkland dot com ¶
18 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 ===
Teelevision ¶
11 years 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)));
}
?>
DO ¶
16 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;
}
?>
8ilO ¶
7 years ago
A min_by function:
<?php
function min_by(Array $arr, Callable $func){
$mapped = array_map($func, $arr);
return $arr[array_search(min($mapped), $mapped)];
}
$a = ["albatross", "dog", "horse"];
echo min_by($a, "strlen"); // dog
?>
hava82 at gmail dot com ¶
13 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) );
}
?>
piotr_sobolewski at o2 dot nospampleasenono dot pl ¶
17 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'));
php at keith tyler dot com ¶
14 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
matt at borjawebs dot com ¶
14 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);
?>
johnphayes at gmail dot com ¶
18 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
nonick AT 8027 DOT org ¶
20 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.
alx5000 at walla dot com ¶
19 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
?>
Err ¶
15 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
?>
browne at bee why you dot ee dee you ¶
20 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);
dave at dtracorp dot com ¶
18 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;
}
