C # in lambda - the number of decimal places / first significant decimal

Question

Out of curiosity, would there be an equivalent Lambda expression for the following?

... just started using lambda, so still not familiar with methods like zip ...

//Pass in a double and return the number of decimal places
//ie. 0.00009 should result in 5

//EDIT: Number of decimal places is good.
//However, what I really want is the position of the first non-zero digit 
//after the decimal place.

int count=0;
while ((int)double_in % 10 ==0)
{
double_in*=10;
count++;
}

Answer 1

 double1.ToString().SkipWhile(c => c!='.').Skip(1).Count()

For instance:

double double1 = 1.06696;
int count = double1.ToString().SkipWhile(c => c!='.').Skip(1).Count(); // count = 5;

double double2 = 16696;
int count2 = double2.ToString().SkipWhile(c => c!='.').Skip(1).Count(); // count = 0;

Answer 2

Math.Ceiling(-Math.Log(double_in, 10))

Answer 3

InfiniteSequence,

/// <summary>
/// Returns an inifinte sequence of integers starting with 1
/// </summary>
public static IEnumerable<int> InfiniteSequence() {
  int value = 0;
  while (true) {
    yield return ++value;
  }
}

( .NET:)...)

var count = InfiniteSequence().Select(i => (int)(double_in * Math.Power(10,i))).TakeWhile(v=>v%10==0).Count();

( , 10) .

Answer 4

, .

Math.Max(0, num.ToString().Length - Math.Truncate(num).ToString().Length - 1)