(Not recommended) Write boundary condition file
wbound is not recommended. Use
Create a 2-D geometry and specify boundary conditions in the PDE Modeler app, export them to the MATLAB® workspace, and then write the boundary conditions to a file.
Start the PDE Modeler app and draw a unit circle and a unit square.
pdecirc(0,0,1) pderect([0 1 0 1])
C1-SQ1 in the Set formula
Use the default Dirichlet boundary condition u = 0 for all
boundaries. To verify the boundary condition, switch to boundary mode by selecting Boundary > Boundary Mode. Use Edit > Select all to select all boundaries. Select Boundary > Specify Boundary Conditions and verify that the boundary condition is the Dirichlet condition with
h = 1,
r = 0.
Export the geometry and the boundary conditions to the MATLAB workspace by selecting the Export Decomposed Geometry, Boundary Cond's option from the Boundary menu.
Decompose the exported geometry into minimal regions. The result is one minimal region with five edge segments: three circle edge segments and two line edge segments.
Write the resulting boundary condition matrix to a file. Name the file
fid = wbound(b,"boundary");
b— Boundary conditions
Boundary conditions, specified as a boundary matrix. Typically, you export a boundary matrix from the PDE Modeler app.
filename— Geometry file name
Geometry file name, specified as a string or a character vector.