Exemplo n.º 1
0
        private static void WeakLearnThread(object o)
        {
            WeakLearnPara para = (WeakLearnPara)o;

            for (int i = para.Start; i < para.Start + para.Count; i++)
            {
                WeakLearn learn = para.Pool[i];
                learn.Distribution = para.AdaBoost.m_dist;
                learn.Train();
                learn.CalcR();
            }

            // foamliu, 2009/03/09, 完成, 通知主训练线程.
            para.DoneEvent.Set();
        }
Exemplo n.º 2
0
        /// <summary>
        /// foamliu, 2009/02/24, 更新权重分布.
        ///
        /// </summary>
        /// <param name="at"></param>
        /// <param name="ht"></param>
        private static void UpdateDistribution(AdaBoost ada, ref double[] dist, double at, WeakLearn ht)
        {
            for (int i = 0; i < ada.m_m; i++)
            {
                Example example = ada.m_t_set.Examples[i];

                int iResult = ht.Predict(example.X);

                // foamliu, 2009/03/04, 更新权重, example.Label.Id 和 iResult 可能的取值均为 -1和+1,
                // 当它们相同, 乘积为1, 整个项 > 0, 乘子 > 1, 权重提升;
                // 当它们不同, 乘积为-1, 整个项 < 0, 乘子 < 1, 权重下降.
                dist[i] = dist[i] * Math.Exp(-at * example.Label.Id * iResult);
            }
        }
Exemplo n.º 3
0
        /// <summary>
        /// foamliu, 2009/02/24, 更新权重分布.
        /// 
        /// </summary>
        /// <param name="at"></param>
        /// <param name="ht"></param>
        private static void UpdateDistribution(AdaBoost ada, ref double[] dist, double at, WeakLearn ht)
        {
            for (int i = 0; i < ada.m_m; i++)
            {
                Example example = ada.m_t_set.Examples[i];

                int iResult = ht.Predict(example.X);

                // foamliu, 2009/03/04, 更新权重, example.Label.Id 和 iResult 可能的取值均为 -1和+1,
                // 当它们相同, 乘积为1, 整个项 > 0, 乘子 > 1, 权重提升;
                // 当它们不同, 乘积为-1, 整个项 < 0, 乘子 < 1, 权重下降.
                dist[i] = dist[i] * Math.Exp(-at * example.Label.Id * iResult);
            }
        }