Add isotropic tensor functions like sqrt(T), exp(T), etc. [Source](https://www.google.at/url?sa=t&source=web&rct=j&url=https://classes.soe.ucsc.edu/cmps161/Winter14/papers/t4/RelatedWork/ItskovFourthOrder.pdf.pdf&ved=0ahUKEwjcnPfCjunXAhWEC-wKHfifBaAQFgg1MAM&usg=AOvVaw1Kx0_SJxhmPOpsZ9p_85AG) Or Eigenvalue/Eigenvector Calculation with the help of LAPACK
Add isotropic tensor functions like sqrt(T), exp(T), etc. Source
Or Eigenvalue/Eigenvector Calculation with the help of LAPACK