Exemplo n.º 1
0
        /// <summary>
        ///   Calculates the variance of the values
        /// </summary>
        /// <param name="values"></param>
        /// <returns></returns>
        public static double Variance(this int[] values)
        {
            var oneByN = 1.0 / values.Length;
            var mu     = values.Sum() * oneByN;

            return(values.Sum(value => Mathh.Pow2(value - mu)) * oneByN);
        }
Exemplo n.º 2
0
        /// <summary>
        ///   Calculates the variance and the mean of the values
        /// </summary>
        /// <param name="values"></param>
        /// <param name="mean"></param>
        /// <returns></returns>
        public static double Variance(this double[] values, out double mean)
        {
            var oneByN = 1.0 / values.Length;
            var mu     = mean = values.Sum() * oneByN;

            return(values.Sum(value => Mathh.Pow2(value - mu)) * oneByN);
        }
Exemplo n.º 3
0
        public static int Sse(this int[] x1, int[] x2)
        {
            var n = x1.Length;
            //if (n != x2.Length)
            //  throw new ArgumentException("x1 and x2 are not in the same length.");
            var result = 0;

            for (var i = 0; i < n; i++)
            {
                result += Mathh.Pow2(x2[i] - x1[i]);
            }

            return(result);
        }
Exemplo n.º 4
0
        /// <summary>
        ///   Calculates the mean squared error.
        /// </summary>
        /// <param name="x1"></param>
        /// <param name="x2"></param>
        /// <returns></returns>
        public static double Mse(this double[] x1, double[] x2)
        {
            var n = x1.Length;

            if (n != x2.Length)
            {
                throw new ArgumentException("x1 and x2 are not in the same length.");
            }

            var result = .0;

            for (var i = 0; i < n; i++)
            {
                result += Mathh.Pow2(x2[i] - x1[i]);
            }

            return(result / n);
        }