The finite element method can create elements that are classified as degenerate. For example, a quad element, with four nodes 1, 2, 3, and 4, may contain duplicate nodes 3 and 4. In this case, node 3 and 4 are located at the same (x, y, z).

The degenerate quad element (above, right) contains three distinct nodes and four distinct integration (Gauss) points. Mechanical APDL's solver calculates element nodal results (like stress and strain and flux, et. al.) at each of the integration points. Hence, element nodal results in the MAPDL result file are stored as though an element is not degenerate (even when it is degenerate). For the element (above, right), the file would contain stress and strain and flux listings for four nodes, 1, 2, 3, and 4.

At nodes that share the same (x,y,z) in an element, it is not necessarily true that the element nodal results are equal for each coincident node. Depending upon the analysis, the element nodal results for the element (above, right) at node 3 may not equal the element nodal results at node 4. During the post processing phase, Mechanical drops the values of all but the first duplicate node at an (x,y,z). The element (above, right) would display the stress and strain and flux contours for nodes 1, 2, and 3 (but not 4).