Recipe 4.15 Finding the Largest or Smallest Valued Element in an Array
4.15.1 Problem
You have an array
of elements, and you want to find the largest or smallest valued
element. For example, you want to find the appropriate scale when
creating a histogram.
4.15.2 Solution
To find the largest element, use max(
):
$largest = max($array);
To find the smallest element, use min(
):
$smallest = min($array);
4.15.3 Discussion
Normally, max( ) returns the larger of two
elements, but if you pass it an array, it searches the entire array
instead. Unfortunately, there's no way to find the
index of the largest element using max( ).
To do that,
you must sort the array in reverse order to put the largest element
in position 0:
arsort($array);
Now the value of the largest element is $array[0].
If you
don't want to disturb the order of the original
array, make a copy and sort the copy:
$copy = $array;
arsort($copy);
The same concept applies to min( ) but use
asort( ) instead of arsort( ).
4.15.4 See Also
Recipe 4.17 for sorting an array;
documentation on max( ) at
http://www.php.net/max, min(
) at http://www.php.net/min,
arsort( ) at
http://www.php.net/arsort, and asort(
) at http://www.php.net/min.
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