The key points that denote the varying trend of the sequence were selected according to some thresholds through one scan of the data.These selected points were used to fit time series linearly.

• 该算法通过一次扫描数据，根据中线距离阈值和非单调序列中极值点保持时间段阈值两个约束条件，选择反映序列趋势变化的关键点，然后线性拟合时间序列。