A little improvement of parseFloat function to handle string in ending with %.

getNumber.js

var f = getNumber('23.7'); // f = 23.7
//var f = getNumber(23.7); // f = 23.7
//var f = getNumber('23.7 px'); // f = 23.7
//var f = getNumber('23.7 %'); // f = 0.237

function getNumber(input) {
    if( typeof input === 'string' && input.slice(-1) === '%') {
    	input = parseFloat(input.slice(0,-1))/100;
    } else {
        input = parseFloat(input);   
    }
    return input;
}