Need a little help for algorithm - php

Question

Right now I have a set of if and elseif to set the height of the div
<?php
if($num == 0){echo 'height:0px;';}
elseif($num > 0 && $num < 10) {echo 'height:3px;';}
elseif($num >= 10 && $num < 22) {echo 'height:7px;';}
elseif($num >= 22 && $num < 45) {echo 'height:16px;';}
elseif($num >= 45 && $num < 50) {echo 'height:33px;';}
elseif($num >= 50 && $num < 67) {echo 'height:36px;';}
elseif($num >= 67 && $num < 79) {echo 'height:48px;';}
elseif($num >= 79 && $num < 88) {echo 'height:56px;';}
elseif($num >= 88) {echo 'height:72px;';}
?>
The problem is that this is copyed 5 times for 5 different divs and think there is better way to do it
Like so :
<?php
function divHeight($maxNum,$number)
{
if($number == 0)
{
echo 'height:0px;' ;
}
elseif($number >= $maxNum)
{
echo 'height:72px;' ;
}
else
{
//here were the algorithm have to be
}
}
?>
I will call it like <?php divHeight(88,$number);?>
The max height of div is 72, now how to calculate the height?
// Edit : This is so simple :X :X but is too late and i havent sleept so
$newHeight = floor($number * 72 / 100);
echo $newHeight;

Answer 1

function mapNumToHeight($num) {
// Max $num => height for that num
$heightMap = array(
0 => 0,
9 => 3,
21 => 7,
44 => 16,
49 => 33,
66 => 36,
78 => 48,
87 => 56,
88 => 72
);
// Store the keys into an array that we can search
$keys = array_keys($heightMap);
rsort($keys);
// We want to find the smallest key that is greater than or equal to $num.
$best_match = $keys[0];
foreach($keys as $key) {
if($key >= $num) {
$best_match = $key;
}
}
return 'height:' . $heightMap[$best_match] . 'px;';
}
mapNumToHeight(3); // height:3px;
mapNumToHeight(33); // height:16px;
mapNumToHeight(87); // height:56px;
mapNumToHeight(88); // height:72px;
mapNumToHeight(1000); // height:72px;