数组中元素的潜在位置和值

Question

Array have a range of keys with it's proper values.

Let's say that array looks like this:

Array
(
    [0] => 0.00
    [2] => 0.60
    [5] => 1.00
    [1] => 0.30
    [3] => 0.90
)

So, it's without key 4.

Since array is in fact a range of elements, value of element with key 4 will be 0.90, or value of element with first lower key value.

What will be best practice to achieve, to get value 0.90 for value of 4 (that does not exist in array).

Hope that my question in not to complicated... Thank you in advance!

Answer 1

I wouldn't call this a best practice, but it would give you the value you expect, that is: the value in the first entry in the array with key lower than the given one.

function findValue( $i, $values ) 
{
    if ( $i < 0 ) die ("Can't compute.");

    if ( !isset( $values[$i] ) )
    { 
        return findValue( $i-1, $values );
    }
    else
    {
        return $values[$i];
    }
}


$values = array(
 0 => 0.0,
 2 => 0.6,
 5 => 1.0,
 1 => 0.3,
 3 => 0.9
);

$searchedValue = findValue(4, $values);