[Dune] Help for gradient calculation

[DHIRENDRA VAIDYA]

I am trying to calculate electric field from -grad(potential). potential is
obtained from solving poisson's equation by finite element method and node
values are stored in block vector. possion's equation is solved simillar to
grid-howto tutorial. now i am stuck in calculating potential gradient with
these node values of potential. i tried calculating gradient of
shapefunction at nodes and then multiply it with potential node value, but
gradient of shapefunction is coming out to be zero at nodes(might be bcoz at
node gradient is undefined). so how to calculate gradient?

On Mon, Jul 11, 2011 at 5:32 PM, Jö Fahlke <jorrit at jorrit.de> wrote:

> Am Mon, 11. Jul 2011, 10:53:38 +0200 schrieb Oliver Sander:
> > Please be more specific when writing questions.
>
> To make the request to be more specific more specific: what kind of
> function
> are you talking about?  For instance, is it a discrete function, and if so,
> what discretization module are you using?
>
> Bye,
> Jö.
>
> --
> Computers are like air conditioners.  Both stop working, if you open
> windows.
> -- Adam Heath
>
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-- 
Warm Regards,
Dhirendra Vaidya
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