Question

Preconditioners improve ____________ of the coefficient matrix.

(a) sparsity

(b) rank

(c) spectral properties

(d) Singularity

This question was addressed to me in an internship interview.

I need to ask this question from Numerical Methods in section Numerical Methods of Computational Fluid Dynamics

Answer 1

Correct choice is (c) spectral properties

The best explanation: For a system of equations to have a better rate of convergence, the coefficient matrix should have a less spectral radius. So, Preconditioners are used to improve the spectral characteristics of a system to give the same solution.