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min
Find lowest value
(PHP 4, PHP 5)
Example 1151. Example uses of min()<?php Related Examples ( Source code ) » min Examples ( Source code ) » Cookie based login form and get last login time Examples ( Source code ) » Starting or Resuming a Session Examples ( Source code ) » strcasecmp Examples ( Source code ) » Quantifier Syntaxes Examples ( Source code ) » String replace with Regular Expressions Examples ( Source code ) » Accessing the Attributes of a Class by Using Functions Examples ( Source code ) » Changing the Value of an Attribute within a Function Examples ( Source code ) » For loop format Examples ( Source code ) » Apache Variables Examples ( Source code ) » Format Codes for Use with date() Examples ( Source code ) » Use Echo to output string Examples ( Source code ) » Define your own exception class Examples ( Source code ) » getdate() Seconds past the minutes Examples ( Source code ) » getdate() Minutes past the hour Examples ( Source code ) » Using popen() to Read the Output of the UNIX who Command Code Examples / Notes » minkevin
The 'undefined' behaviour can bit you badly. I would expect min(undefined, -1000) to return -1000. Not so.
johnphayes
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 08-jul-2002 10:36
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(); ) 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 ! browne
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); alx5000
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 ?> calin
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 nak2
If one of elements is undefided, min() result is underfinded too
nonick
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. dasprid — d
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 $min; } ?> kieran
Further modifications to the minnum function above.. This is for a project where I had to grab an entire column out of a database consisting of values that might be string, might be string representations of numbers (floating point or integer) or might be NULL, and find the minimum NUMERIC value: function minnum($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. dave
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; } merome
Caution : it seems that min() can return a string : min(";",50)=";" (I expected zero) piotr_sobolewski
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
> 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 === |