initmesh: 'Hmax' parameter is not an upper bound on edge lengths
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I am using initmesh() to generate a 2D-mesh in order to discretize a PDE-problem. The parameter 'Hmax' of this matlab function can be used to bound the edge lengths of the triangulation. Beeing precise, the documentation of initmesh() says:
"The Hmax property controls the size of the triangles on the mesh. initmesh creates a mesh where triangle edge lengths are approximately Hmax or less."
However, an easy example on the domain D=[0,1]^2 with Hmax=1 shows, that this is not the case: the generated mesh includes the triangle [0,0] - [1,0] - [0,1] with maximum edge length sqrt(2).
b1=0;b2=1; d0=decsg([3 4 b1 b2 b2 b1 b1 b1 b2 b2]');
Indeed, after a few experiments it seems like the parameter 'Hmax' is a treshold on the max-min-edge length, i.e. it seems to be a bound on max(h_min(T)) over all triangles T in the triangulation, where h_min(T) denotes the minimal edge length of the triangle T.
Is there a reason for this? Do I misunderstand something?
Thank you in advance!