Re: [Getfem-users] specification of Grad expression

[Yves Renard]

Dear Tetsuo,

It is not easy to find, but the index order in a tensor is shortly 
explained in the following part of the documentation :

http://getfem.org/project/appendixA.html#example-of-elementary-matrix

For a gradient, each row is the gradient of a component in such a way 
that Grad u * h is the derivative in the direction h (so in a sense it 
is a derivative)

Best Regards,

Yves


Le 11/03/2019 à 12:17, Tetsuo Koyama a écrit :
> Dear GetFEM++ Project
>
> Sorry to ask many question.
> I want to ask about regular expression.
> When using "Grad_" in regular expression in 3D MeshFem. It seems that
> it create 3D tensor. My question is that the meaning of line and
> column.
> In my forecast, the line is the direction of variable and column is
> the direction of gradient. Is it correct?
> Is there any related part in the document?
> Thank you for reading.
>
> Best Regard Tetsuo.

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  Yves Renard (address@hidden)       tel : (33) 04.72.43.87.08
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