226Bproject 1

Residual type Error Estimator

The purpose of this project is to code the residual type error estimator for solving Poisson equation.

AFEM

Read subroutine Lshape.m or Crack.m on the general processdure of adaptive finite element methods.

Your task is to replce the subroutine estimateW21 by a residual type error estimator.

Data structure

Read Chapter 2: Triangulation to get familar with the following data structure

node, elem, edge, edgeRing, neighbor, elem2edge

Formula of error estimator

You can find the detailed formulation of eta from the lecture notes. Note that the error indicator is elementwise, while the jump of gradient is edgewise. You need to transfer efficiently between triangles and edges.