Fast, fully vectorised version of the Simpson's method for 3D domains. This code avoids the use of any for loops etc. For a given level of accuracy it can be an order of magnitude or more faster than triplequad.
Examples are provided within the code.
ans = simp3D('func3D',xs,xe,ys,ye,zs,ze,NX,NY,NZ)
func3D - 3D function that accepts vector inputs...