Spline approximation and quasi-interpolation techniques are essential tools in numerical analysis and computational mathematics, particularly for function approximation and data fitting.

Optimal control and spline interpolation techniques are essential tools in mathematical modeling and computational geometry. These methods are widely used for data fitting, curve design ...

But [Marb] has an answer for that; after gathering data at each wavelength, he applies a cubic spline interpolation to derive the spectrum. It’s demonstrated in the video below using chlorophyll ...