Question

Conjugate gradient algorithm can be accelerated by using _________

(a) Algorithm strategies

(b) Preconditioning strategies

(c) Conditioning strategies

(d) Computer strategies

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I'm obligated to ask this question of Conjugate Gradient Method for Equation Solving in section Matrix Algebra and Gaussian Elimination of Finite Element Method

Answer 1

The correct choice is (b) Preconditioning strategies

The best explanation: Conjugate gradient algorithm can be accelerated by using preconditioning strategies. Preconditioner of a matrix has to be symmetric positive definite and fixed and that cannot be changed from iteration to iteration. The behavior of the preconditioned conjugate gradient method may become unpredictable.