Basis functions for general Hsieh‐Clough‐Tocher triangles, complete or reduced

Abstract

In this note, we give the basis functions (shape functions) for Hsieh‐Clough‐Tocher triangles, complete or reduced. In order to take the best advantage of symmetry and for simplicity, we derive these functions for a general triangle by using simultaneously the ‘area co‐ordinates’ and the so‐called ‘eccentricity parameters’. We conclude with some remarks concerning the implementation.

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