A new BFGS-type formula and a new BFGS-type method with the Wolfe-Powell(WWP) step size are presented. The global convergence property is provided and the nurnberical results indicate that the new method is very encouraging.

• 提出利用Wolfe-Powell(WWP)的BFGS类型公式和BFGS类型方法，其具有全局收敛性质且数值试验表明该方法是可行的。