Gets the standard deviation

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/*
Copyright (c) 2010 <a href="http://www.gutgames.com">James Craig</a>

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namespace Utilities.Math
{
    /// <summary>
    /// Various math related functions
    /// </summary>
    public static class MathHelper
    {
        #region Public Static Functions
        /// <summary>
        /// Gets the mean value from a list
        /// </summary>
        /// <param name="Values">The list of values</param>
        /// <returns>The mean/average of the list</returns>
        public static double Mean(System.Collections.Generic.List<int> Values)
        {
            if (Values.Count == 0)
                return 0.0;
            double ReturnValue = 0.0;
            for (int x = 0; x < Values.Count; ++x)
            {
                ReturnValue += Values&#91;x&#93;;
            }
            return ReturnValue / (double)Values.Count;
        }

        /// <summary>
        /// Gets the mean value from a list
        /// </summary>
        /// <param name="Values">The list of values</param>
        /// <returns>The mean/average of the list</returns>
        public static double Mean(System.Collections.Generic.List<double> Values)
        {
            if (Values.Count == 0)
                return 0.0;
            double ReturnValue = 0.0;
            for (int x = 0; x < Values.Count; ++x)
            {
                ReturnValue += Values&#91;x&#93;;
            }
            return ReturnValue / (double)Values.Count;
        }


        /// <summary>
        /// Calculates the variance of a list of values
        /// </summary>
        /// <param name="Values">List of values</param>
        /// <returns>The variance</returns>
        public static double Variance(System.Collections.Generic.List<double> Values)
        {
            if (Values == null || Values.Count == 0)
                return 0;
            double MeanValue = Mean(Values);
            double Sum = 0;
            for (int x = 0; x < Values.Count; ++x)
            {
                Sum += System.Math.Pow(Values&#91;x&#93; - MeanValue, 2);
            }
            return Sum / (double)Values.Count;
        }

        /// <summary>
        /// Gets the standard deviation
        /// </summary>
        /// <param name="Values">List of values</param>
        /// <returns>The standard deviation</returns>
        public static double StandardDeviation(System.Collections.Generic.List<double> Values)
        {
            return System.Math.Sqrt(Variance(Values));
        }

        #endregion
    }
}