upwind scheme in Mathematica?



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    On 5/19/07 at 4:48 AM, XXXX@XXXXX.COM wrote: >Why do I get? >In[4]:= >Minimize[(x^4-6 x^2+1)^2,{x}] >Out[4]= >{1,{x->0}} =46WIW, version 6 returns In[4]:= Simplify[Minimize[(x^4 - 6*x^2 + 1)^2, {x}]] Out[4]= {0, {x -> -1 - Sqrt[2]}}

upwind scheme in Mathematica?

Postby Santhosh » Wed, 02 Sep 2009 16:51:48 GMT

hi all,

I am trying to solve convection-diffusion-reactions(in time and one
space coordinate) equations with NDSolve. Most of the time I am not
getting solution to my problem as solver fails to converge. I guess
the problem is very stiff and convection dominated. When I use upwind
difference scheme in fortran, I get the solution easily. How can use
upwind in NDSolve?
What is the method mathematica uses to solve pdes?

any comments are welcome.

Thanks in advance.

Re: upwind scheme in Mathematica?

Postby Santhosh » Sun, 06 Sep 2009 18:37:49 GMT

din NDSolve?

I am still looking of answer!

Re: upwind scheme in Mathematica?

Postby Mark Fisher » Mon, 07 Sep 2009 20:37:22 GMT


Mathematica uses the method of lines to solve pdes numerically. To
read about it, paste  "tutorial/NDSolvePDE" (without the quotes) into
the search box in the help system. (I don't know anything about upwind


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