triangle_grid, a FORTRAN90 code which generates a grid of points over the interior of a triangle in 2D.
Starting with any 3 points A, B, and C that define a triangle, we can divide each side of the triangle into N subintervals, and create a triangular grid. This defines ((N+1)*(N+2))/2 points that lie on the intersections of grid lines. The arrangement is suggested by this diagram:
X
9 X
8 9 X
7 8 9 X
6 7 8 9 X
5 6 7 8 9 X
4 5 6 7 8 9 X
3 4 5 6 7 8 9 X
2 3 4 5 6 7 8 9 X
1 2 3 4 5 6 7 8 9 X
0 1 2 3 4 5 6 7 8 9 X
The library includes a routine which allows the user to pick an arbitrary triangle and an arbitrary number of subdivisions. It then returns the triangular gridpoints defined by that choice.
The computer code and data files described and made available on this web page are distributed under the MIT license
triangle_grid is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.
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