Nonlinear least-squares inversion by the conjugate gradient method

5 Nonlinear least-squares inversion by the conjugate gradient method This method uses the same ideas as the regularized conjugate gradient method  

However, the regularized steepest descent dircc tions are now determined according to the formula for the least-squares method  

Det ermination of the length of iteration step, a coefficient /e , can be based on the linear or paraliolic line seardi  

Solution of this minimization problem gives the following best estimation for the Icngtli of tlu stci) using a linear line search  

One can use a parabolic lino search also (Fletcher, 1985) to improve the convergence rate of the RCG method. 

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