Extracting the exponent and mantissa of a Javascript Number

Question

Is there a reasonably fast way to extract the exponent and mantissa from a Number in Javascript?

AFAIK there\'s no way to get at the bits behind a Number in Javascri

Answer 1

If you only need mantissa length,

Number.prototype.mantissaLength = function(){
    var m = this.toString(), d = m.indexOf('.') + 1;
    return d? m.length - d:0;
}

var x = 1234.5678;
var mantL = x.mantissaLength();