Diagonal elements of a volTensorField
 

Dear All,

I need to compute the diagonal elements of a volTensorField. The tensor field has the form,

volTensorField tmp ("tmp", fvc::grad(U));

It seems OpenFoam 1.6 doesn't have a function like diag(tmp). Does OpenFoam 1.7 have such kinds of function? Do any people know how to compute the diagonal elements?

Many thanks,
Y. J.

If you want the sum of the diagonal elements then:

volScalarField trTmp = tr(tmp);

If you just want the diagonal components, then

tmp.xx()
tmp.yy()
tmp.zz()

will provide the individual fields.