Round number to nearest fraction with PHP

Sometimes when you are trying to code small functions you realize that some one must have done the same thing before and you realize that google is as usual your friend in need!

I was trying to compile a helper function to round a float to what ever nearest fraction i needed. I found numerous examples on how to do this best while googleing.

function roundToNearestFraction( $number, $fractionAsDecimal )
{
     $factor = 1 / $fractionAsDecimal;
     return round( $number * $factor ) / $factor;
}

// Round to nearest fifth
echo roundToNearestFraction( 3.78, 1/5 );

// Round to nearest third
echo roundToNearestFraction( 3.78, 1/3 );