https://nl.mathworks.com/help/pde/ug/pde.femesh.html
FEMesh - Mesh object - MATLAB
An FEMesh object contains a description of the finite element mesh.
meshobjectmatlab
https://kr.mathworks.com/help/pde/ug/pde.femesh.meshtopet.html
meshToPet - [p,e,t] representation of FEMesh data - MATLAB
This MATLAB function extracts the legacy [p,e,t] mesh representation from a FEMesh object.
p erepresentationdatamatlab