The support vector machine composed by least sequence and directed acyclic graph algorithm has been used in paper currency identification , shows the advantages of capability in dealing with scared samples , nonlinear and high dimensions 将次序最小优化改进算法和有向无环图算法构建的支持向量机用于货币识别，充分发抨了支持向量机解决小样本、非线性和高维模式识别问题的优点。
