Planar Quadrangle Quality Measures: Is There Really A Choice?
نویسنده
چکیده
In this article some new results are presented about planar quadrangle quality measures. On the one hand, a modi cation of the triangle quality measure based on the Frobenius norm is proposed, in order to comply with the case where the reference element is no longer equilateral, but a right isosceles triangle. Provided this modi cation, a natural use of the Frobenius norm for quadrangular elements is proposed. On the other hand, generalizations of two triangle quality measures, based on edge to inradius ratios, to planar quadrangles are proposed and justi ed, and their limitations, depending on user's expectations, are exhibited, justifying the use of a more complex quality measure.
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