Based on the MASS kde2d() function, but heavily simplified; it's just tcrossprod() now.

Based on the MASS kde2d() function, but heavily simplified; it's just tcrossprod() now.

kde2d_faster(dens.x, dens.y)

Arguments

dens.x

Contribution of all cells to densities of the x-axis grid points.

dens.y

Contribution of all cells to densities of the y-axis grid points.