jQuery / Javascript - How do I convert a pixel value (20px) to a number value (20)

I know jQuery has a helper method for parsing unit strings into numbers. What is the jQuery method to do this?

var a = "20px";
var b = 20;
var c = $.parseMethod(a) + b;

Solution 1:

No jQuery required for this, Plain Ol' JS (tm) will do ya,

parseInt(a, 10);

Solution 2:

More generally, parseFloat will process floating-point numbers correctly, whereas parseInt may silently lose significant digits:

parseFloat('20.954544px')
> 20.954544
parseInt('20.954544px')
> 20

Solution 3:

$.parseMethod = function (s)
{
    return Number(s.replace(/px$/, ''));
};

although how is this related to jQuery, I don't know

Solution 4:

 var c = parseInt(a,10);