Posted by David T. Ashley on 07/03/07 21:25

I have an array of a few hundred integers, ordered in ascending order.

Given an integer input, I'd like to find the index in the array of the
element $array[$i] such that it is equal to or less than the input but
$array[$i+1] is larger.

I couldn't find a function to deal with arrays that does anything except
look for an exact match.

Are there any built-in functions that will search in a "bracketed" way
rather than look for an exact match?

For example,

$a = array( 10, 50, 250, 1000, 20000, 40000 );

If the input is 20,039 (for example), I'd want the output of the function to
be 4, because $a[4] is the element just below 20,001.

Any such built-in function?
--
David T. Ashley (dta@e3ft.com)
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