find the standard deviation of all elements in an array in csharp

To find the standard deviation of all elements in an array in C#, you can use the following code:

main.cs
public static double CalculateStandardDeviation(double[] values)
{
    double mean = values.Sum() / values.Length;
    double variance = values.Select(val => (val - mean) * (val - mean)).Sum() / values.Length;
    double standardDeviation = Math.Sqrt(variance);
    return standardDeviation;
}
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This method first calculates the mean (average) of all the elements in the array. It then calculates the variance, which is the average of the squared differences of each element from the mean. Finally, it takes the square root of the variance to get the standard deviation.

You can call this method by passing in your array of values:

main.cs
double[] values = new double[] { 1.2, 3.4, 2.0, 4.5, 6.7 };
double standardDeviation = CalculateStandardDeviation(values);
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Note that the above code assumes that the array contains at least two elements. If the array has only one element, the variance is zero and the standard deviation is also zero.