Question

I’m looking to get the scale and precision from a number in the following example.

var x = 1234.567;

I’m not seeing any .scale or .precision functions built in and I’m not sure what the best way to right one is.

Answer 1

var x = 1234.567;

var parts = x.toString().split('.');

parts[0].length; // output: 4 for 1234

parts[1].length; // output: 3 for 567

NOTE

Javascript has toPrecision() method that gives to a number with specified length.

For example:

var x = 1234.567;

x.toPrecision(4); // output: 1234

x.toPrecision(5); // output: 1234.5

x.toPrecision(7); // output: 1234.56

But

x.toPrecision(5); // output: 1235

x.toPrecision(3); // output: 1.23e+3 

and so on.

According to comment

Is there a way to check that the string contain .?

var x = 1234.567

x.toString().indexOf('.'); // output: 4

Note

.indexof() return first index of target else -1.