Currency Filter For Large Amount In Angular

I am building an angular app involving large amounts. I'd like to shorten the way their are displayed so I built a quick and dirty filter replacing '1000000000' by '$1.0Bn' for exa

Solution 1:

You can compute a few things using Mathematical logarithm log!. This will help you knowing the number of digits your input has.

Example (log is base 10 logarithm, ln is napierian logarithm) :

log(12345678910) = ln(12345678910)/ln(10) = 10

Here, 10 is the number of digits after the first '1'.

Based on this information you can compute a simplified value, and then round it with toFixed! (This works with IE5.5+, Javascript 1.5, I assumed you get it when you use AngularJS)

A complete example below :

var number = 12345678910;

var digits = 2;
var suffix = ["", "K.", "M.", "B."];

var nbDigits = Math.round(Math.log(number)/Math.LN10);
var power = nbDigits - nbDigits%3;

var tmp = number/ Math.pow(10, power);
var suffixIndex = Math.min(3, power/3);

var result = "$" + tmp.toFixed(digits) + " " + suffix[suffixIndex];