Hello;

I have a 2D grid generated using polar coordinates in a plane, and thus the elemental grid panels are NOT squares.

At each grid point, I've the tabulated function value Y, the first two derivatives dY/dr & dY/dth, and the cross-derivative d2Y/drdth.

Can I still apply the bicubic interpolation (Fortran) routines BCUCOF() & BCUINT() to accurately interpolate the function Y at (r1,th1) within the non-rectangular "sector of an annulus" grid cell ??

Thank you kindly.
Monir