Dougy Mak's Blog

I just discovered a few cool functions:

• ceil() – Round fractions up
• floor() – Round fractions down
• round() – Rounds a float

I’m guessing ceil() is short for ceiling. When looking up, you have a ceiling whereas when looking down, you have a floor(). The functions’ names correspond to their actual function which makes it pretty easy to remember. And then we also have round which is just basic rounding.

ceil() examples:

<?php
echo ceil(4.3); // 5
echo ceil(9.999); // 10
echo ceil(-3.14); // -3
?>

floor() examples:

<?php
echo floor(4.3); // 4
echo floor(9.999); // 9
echo floor(-3.14); // -4
?>

round() examples:

<?php
echo round(3.4); // 3
echo round(3.5); // 4
echo round(3.6); // 4
echo round(3.6, 0); // 4
echo round(1.95583, 2); // 1.96
echo round(1241757, -3); // 1242000
echo round(5.045, 2); // 5.05
echo round(5.055, 2); // 5.06
?>
<?php
echo round(9.5, 0, PHP_ROUND_HALF_UP); // 10
echo round(9.5, 0, PHP_ROUND_HALF_DOWN); // 9
echo round(9.5, 0, PHP_ROUND_HALF_EVEN); // 10
echo round(9.5, 0, PHP_ROUND_HALF_ODD); // 9echo round(8.5, 0, PHP_ROUND_HALF_UP); // 9
echo round(8.5, 0, PHP_ROUND_HALF_DOWN); // 8
echo round(8.5, 0, PHP_ROUND_HALF_EVEN); // 8
echo round(8.5, 0, PHP_ROUND_HALF_ODD); // 9
?>