鲍威尔方法是鲍威尔于1964年提出的，以后又经过他本人的改进。该方法是一种有效的共轭梯度方向法，它可以在有限步内找到二次函数的极小点。对于非二次函数只要具有连续的二阶导数，用这种方法也是有效的。-Powell method is proposed in 1964, and later through his own improvements. This method is an effective method of conjugate gradient direction, it can find the minimum point of a quadratic function in finite steps. For as long as a non-quadratic function has a continuous second derivative, with this method is also effective.