float value extraction in javascript

Question

how can i extract float value like (0.9) to be a whole integer value (9) in JavaScript?

example

var total = 67.9; 
something to process  var whole var DEC to be like 
var whole = 67;
var DEC = 9;

why 9 and not 0.9? what should happen with numbers, like 42.321? should it return dec = 321? — Nina Scholz
– Nina Scholz, Commented Nov 13, 2016 at 9:51
In general case it's not possible (due to finite precision). There is a chance you're doing something in a wrong way and you better explain the original problem you're solving. — zerkms
– zerkms, Commented Nov 13, 2016 at 10:00
@zerkms It's not possible if you're working with numbers only (and yes, I tried out of curiosity - it almost never gives the right answer), but since this is a representation problem we might as well work with strings. — MaxArt
– MaxArt, Commented Nov 13, 2016 at 10:06
@MaxArt var total = 67.9; --- well, in the question they are dealing with numbers not strings. Since not every number is correctly representable - you cannot tell (in runtime) whether the numeric literal and its string representation are the same thing. — zerkms
– zerkms, Commented Nov 13, 2016 at 10:08

MaxArt · Accepted Answer · 2016-11-13 09:53:26Z

2

The simplest way I can think of is this:

var string = total.toString();
var dotidx = string.indexOf(".");
var dec = dotidx >= 0 ? +string.slice(dotidx + 1) : 0;

Notice that it doesn't work with numbers in exponential forms.

answered Nov 13, 2016 at 9:53

MaxArt

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Comments

Yogesh Patel · Accepted Answer · 2016-11-13 10:03:59Z

2

There are many ways to find a result. I give you one simple solution.

var total = 67.9
var splitVal = total.toString().split(".")
var whole = splitVal[0], var desc = splitVal[1] || 0

and if you want to convert whole and desc in number then multiply by 1.

var whole = splitVal[0] * 1

answered Nov 13, 2016 at 9:53

Yogesh Patel

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This would return undefined/NaN if total is actually an integer.

we can set var desc = splitVal[1] || 0. Thanks MaxArt