Converting Exponential Double value to int in C#

Question

I want to get the only that part which is before the point but I am unable to get it with every method. My value is 1.734565456765434E-06. I want to convert it into just 1

Do you know what number that is supposed to represent? It's not even close to 1. — Jeff Mercado, Jun 17 '15 at 04:47
What about 2E+04 - should it be just 2? Some explanation of how you want to convert value would make question more concrete. Adding code you've tried will make question ok for SO. — Alexei Levenkov, Jun 17 '15 at 04:49
http://stackoverflow.com/questions/374316/round-a-double-to-x-significant-figures should give you good starting point. — Alexei Levenkov, Jun 17 '15 at 05:02

score 2 · Accepted Answer · edited Apr 13 '17 at 12:19

Looks like you're trying to get the most significant digit of a number.

var n = 1.734565456765434E-06;
var exp = Math.Floor(Math.Log10(n)); // -6
var result = Math.Floor(n / Math.Pow(10, exp)); // 1

This can be generalized to this:

var n = 1.734565456765434E-06;
var nDigits = 1; // 1 significant digit
var exp = Math.Floor(Math.Log10(n));
var result = Math.Floor(n / Math.Pow(10, exp + (1 - nDigits)));

score 0 · Answer 2 · answered Jun 17 '15 at 09:05

If you are only interested in the first digit of your scientific representation, try this:

var number = 1.734565456765434E-06;
var numberString = number.ToString("E");
var firstDigitString = numberString.Substring(0, 1);
var firstDigit = int.Parse(firstDigitString);

Converting Exponential Double value to int in C#

2 Answers2