Fast 3D grid interpolation

Hello everybody,

I need a way to do a fast (mesh)grid interpolation after I rotated this grid with a matrix operation. I have magnetic field Bx,By,Bz component values for x-,y-z- Coordinate values arranged in a meshgrid. I need to do many steps of rotations and evaluate Bx By Bz at specific points in each step, but there are sometimes no data in this points (see my sketch. This sketch is just 2D, but its the same problem in 3D actually). So I need to interpolate the rotated grid to get the data for specific evaluation points...

"griddata" becomes super slow for many steps and bigger meshgrids.... any faster recommendations...?

Thanks in advance!!

Oliver

[darova]

Can this duplicate question be closed?