Fletcher-Reeves approach

The conjugate gradient method is one of the oldest in the Fletcher-Reeves approach, the search direction is given by... 

The conjugate gradient (CG) algorithm is one of the older methods and, strictly speaking, is not a quasi-Newton method. However, it is the method of choice for very large problems where the storage of the Hessian is not practicable. In the Fletcher-Reeves approach the search direction is given by... 

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