Question

The error due to the discretization of the partial differential equation is called as ______________

(a) round-off error

(b) discretization error

(c) truncation error

(d) iteration error

I have been asked this question in a job interview.

This interesting question is from Discretization Aspects topic in chapter Basic Aspects of Discretization, Grid Generation with Appropriate Transformation of Computational Fluid Dynamics

Answer 1

The correct answer is (c) truncation error

For explanation I would say: Truncation error arises when partial differential equations are approximated. Usually, the partial differential equations are approximated using a series expansion of infinite terms. The higher order terms are cut-off while approximating this series. So, it is called truncation error.