实现数值计算的简单算法code 包括：非线性最小二乘问题、共轭梯度法、拟牛顿法、最速下降法与牛顿法、线搜索技术、乘子法程序、二次规划(A simple algorithm for numerical calculation, including nonlinear least squares problem, conjugate gradient method, quasi-Newton method, steepest descent method and Newton method, lin