In a FEM mesh, does the order of node numbering in an element has any importance?
I'm currently trying to code my own FEM solver, which seems to work fine with quadrilateral elements, however I'm having difficulties whith triangular meshes, which yield different results when renumbering the nodes in the elements.
The solver yields different results if I define e.g. element $$ as $(1) (5) (4)$ or $(5) (4) (1)$
Is this a known issue, or is there something wrong with my code?