CALL LNCZS(X,FX,NPTS,NTERMS,X0,FX0,FPX0,SAVE,INIT) -- This subroutine performs a Lanczos sigma smoothing interpolation with derivative. FCTR: LN X - Independent variable array, must be equally spaced. FX - Dependent variable array. NPTS - Number of points in the above arrays. NTERMS - Number of terms (harmonics) to be used, NTERMS < NPTS. X0 - Point for which the interpolation is to take place. FX0 - Interpolated value at X0. FPX0 - Derivative of the interpolation at X0. SAVE - Storage array dimensioned at least 2*NTERMS+4 in the calling program. INIT - Flag to initialize the interpolation when non-zero, set to zero upon completion. >>>>> Note: Points must be equally spaced. <<<<<