Demo for creating the mesh for an annulus.

examples/meshes/annulus.m

+%% Example Mesh
+% create a annulus geometry and (refined) mesh
+clear all; addpath([ '..' filesep '..' filesep ]);
+
+%% Describe the goemetry of the problem for the mesh generator
+% refinement functions
+nfr = mgen.MgNormFunction( mgen.MgNormFunctionType.Quadratic );
+nfc = mgen.MgNormFunction( mgen.MgNormFunctionType.Quadratic );
+% create all geo points
+gp1 = mgen.MgGeoPoint( [1.0, 0.0] );
+gp2 = mgen.MgGeoPoint( [2.0, 0.0] );
+gp3 = mgen.MgGeoPoint( [0.0, 2.0] );
+gp4 = mgen.MgGeoPoint( [0.0, 1.0] );
+% create all geo lines
+gl1 = mgen.MgGeoLine2Point( [gp1, gp2], 4, nfr ); % ask for 4 grid nodes along this line
+gl2 = mgen.MgGeoLine2Point( [gp4, gp3], 2, nfr ); % % this will adapt automatically
+gl3 = mgen.MgGeoLine2PointSegment( [gp2, gp3], 2.0, 8, nfc ); % ask for 5 grid nodes along this line
+gl4 = mgen.MgGeoLine2PointSegment( [gp1, gp4], 1.0, 2, nfc ); % this will adapt automatically
+% create all geo areas
+ga1 = mgen.MgGeoArea4LineAnnulus( [gl1, gl3, gl2, gl4] );
+% create geo object and generate the mesh
+geo = mgen.MgGeo( [gp1, gp2, gp3, gp4], [gl1, gl2, gl3, gl4], [ga1] );
+% print geo and mesh data info
+% fprintf(geo.print());
+% plot mesh
+cla; clf;
+fig = figure(1); subplot('Position',[0.05 0.05 0.90 0.90]); axis equal; hold on;
+geo.plot();