bsplin3val 3d spline arbitrary derivative evaluation function [dfp]=bsplin3val(xp,yp,zp,tl,der) xp, yp, zp real vectors or matrices of same size tl tlist of type "splin3d", defining a 3d tensor spline (called s in the following) der vector with 3 components [ox,oy,oz] defining which derivative of s to compute. dfp vector or matrix of same format than xp, yp and zp, elementwise evaluation of the specified derivative of s on these points. While the function interp3d may compute only the spline s and its first derivatives, bsplin3val may compute any derivative of s. The derivative to compute is specified by the argument der=[ox,oy,oz] : So der=[0 0 0] corresponds to s, der=[1 0 0] to ds/dx, der=[0 1 0] to ds/dy, der=[1 1 0] to d2s/dxdy, etc... For a point with coordinates (xp(i),yp(i),zp(i)) outside the grid, the function returns 0. splin3d interp3d 5.4.0 previously, imaginary part of input arguments were implicitly ignored.