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A tessellation of a part of the Euclidean plane or Euclidean space by simple shapes, such as triangles or tetrahedra, in an irregular pattern.
| Fig. 1. Example of unstructured grid |
It is usually contrasted against Structured grid.
See also
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Formal science / Mathematics / Geometry / Grid
[ Structured grid ] [ Delaunay grid ] [ Voronoj grid ]