Modified Newton Raphson method

The algorithm is based on Newton-Raphson method for solution of non-linear problems. The method is better in some case of solution. It is tangent method too, but calculation of stiffness of structure is calculated only one on the beginning and it is used in all next iterations. It means that convergence needs much more iterations, but in case of huge structure it can be faster, than calculate stiffness matrix of structure several times.

Note : This method requires that a 1D member is divided to at least four (4) finite elements. Usually, such division is adjusted automatically whenever Modified Newton-Raphson method is selected for calculation.