Builds a discretization grid covering the two-dimensional unit simplex, with specified number of points and minimal distance from the boundary.
discretize(npoints =40, eps =0.001, equi =FALSE)
Arguments
npoints: The number of grid nodes on the squared grid containing the desired triangle.
eps: Positive number: minimum distance from any node inside the simplex to the simplex boundary
equi: logical. Is the simplex represented as an equilateral triangle (if TRUE) or a right triangle (if FALSE) ?
Returns
A list containing two elements: X and Y, vectors of size npoints, the Cartesian coordinates of the grid nodes.
Details
The npoints*npoints grid covers either the equilateral representation of the simplex, or the right angled one. In any case, the grid is rectangular: some nodes lie outside the triangle. Density computations on such a grid should handle the case when the point passed as argument is outside the simplex (typically, the function should return zero in such a case).
Note
In case equi==TRUE, epsilon is the minimum distance from any node inside the simplex to the simplex boundary, after transformation to the right-angled representation.