54        constexpr Scalar n[10] = {
 
   55            0.11670521452767e4, -0.72421316703206e6, -0.17073846940092e2,
 
   56            0.12020824702470e5, -0.32325550322333e7, 0.14915108613530e2,
 
   57            -0.48232657361591e4, 0.40511340542057e6, -0.23855557567849,
 
   61        const Scalar sigma = temperature + n[8]/(temperature - n[9]);
 
   63        const Scalar A = (sigma + n[0])*sigma + n[1];
 
   64        const Scalar B = (n[2]*sigma + n[3])*sigma + n[4];
 
   65        const Scalar C = (n[5]*sigma + n[6])*sigma + n[7];
 
   68        Scalar tmp = 2*C/(sqrt(B*B - 4*A*C) - B);
 
 
   85        constexpr Scalar n[10] = {
 
   86            0.11670521452767e4, -0.72421316703206e6, -0.17073846940092e2,
 
   87            0.12020824702470e5, -0.32325550322333e7, 0.14915108613530e2,
 
   88            -0.48232657361591e4, 0.40511340542057e6, -0.23855557567849,
 
   94        const Scalar beta = pow((pressure/1e6 ), (1./4.));
 
   95        const Scalar beta2 = power(beta, 2);
 
   96        const Scalar E = beta2 + n[2] * beta + n[5];
 
   97        const Scalar F = n[0]*beta2 + n[3]*beta + n[6];
 
   98        const Scalar G = n[1]*beta2 + n[4]*beta + n[7];
 
  101        const Scalar D = ( 2.*G)/(-F -sqrt(power(F,2) - 4.*E*G));
 
  102        return (n[9] + D - sqrt(power(n[9]+D , 2) - 4.* (n[8] + n[9]*D)) ) * 0.5;