# triangle_grid

triangle_grid, a MATLAB 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.

### Languages:

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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### Source Code:

Last revised on 06 April 2019.