ИСТИНА

The scattering of plane monochromatic electromagnetic wave on dielectric ball filled by optically inhomogeneous matter is considered. CAS Maple is able to solve analytically linear ordinary differential equations for coefficients of the field in several cases, including the Lüneburg lens. In this last case Maple return the expressions in Whittaker and Heun functions. However, there are difficulties at work with these functions in Maple: sometimes the values of the functions are very large, their graphs have strange jumps and structures which are typical for graphs found with big rounding errors. In our talk we compare the results found in Maple and the results that we got using Frobenius series in CAS Sage.