Hi, I am a master student comes from USM in Malaysia. I dont know my problem should placed on differential forum or high energy physics forum. Anywhere, My current study is high energy physics subject and my main study is focus on monopole instanton solution in static form which did not include time, i using the Lagrangian to generate out the 12 set equations of motion with 8 variables, the software that i use is Matlab with Optimization toolbox- the algorithm that i use inside the package is trusted reflective region and the numerical method that i used is finite difference method. However, it did not converge. I have tried to reproduce the Jutta Kunz paper-monopoles solution with 6 set of partial differential equation with 6 variables and its work well and i also obtain the Higgs field [itex]\Phi(r,\theta)[/itex] of monopole successfully. The variables that in the set of equations of motion is in r and [itex]\theta[/itex] form which means as A(r,[itex]\theta[/itex]). So any suggestion for using Matlab to solve the 12 set equations of motion (PDE form) with 8 variables.