and the Lame constant lambda are now calculated and stored after any
are set using
IsotropicT(ifstreamT& in);
void Set_E_nu(double E, double nu);
void Set_mu_kappa(double mu, double kappa);
and can be accessed using
double Young(void) const;
double Poisson(void) const;
double Mu(void) const;
double Kappa(void) const;
double Lambda(void) const;