| e01bac | nag_1d_spline_interpolant Interpolating function, cubic spline interpolant, one variable |
| e01bec | nag_monotonic_interpolant Interpolating function, monotonicity-preserving, piecewise cubic Hermite, one variable |
| e02bac | nag_1d_spline_fit_knots Least-squares curve cubic spline fit (including interpolation), one variable |