Re: Non linear problem, linearized, how to solve?

[Daniel Wheeler]

Thanks for your interest. On Mar 29, 2006, at 7:55 AM, nelson - wrote: hi all,   i'm resolving a non linear problem. Using a fixed point iteration, i have to solve my equation for the variable d = u_{new non linear step} - u_{old non linear step}. Can i do this in FiPy? I am not sure what the above equation represents. If you can be more explicit it would help. FiPy doesn't include non-linear solvers. You would have to write your own non-linear solver. Generally, we just iterate within the time step until a solution is found and then move on to the next step when a sufficient tolerance has been reached. After d is "little" in norm, i have to start a new timestep (I use a method similar to newton method). I'm planning to make some models involving Richards Equation (an equation used in groundwater modeling), i hope they will be included into fipy, if it will be possible :) We don't expiclitly incude any equations in FiPy. We have the general terms and the user builds up the equations of interest in the input file. good day,   nelson ------------------------------------- Daniel Wheeler Telephone: (301) 975-8358