# [Gmsh] Scalar product of complex vector fields from different views in Gmsh ?

**Zacharie De Grève**
zacharie.degreve at umons.ac.be

*Mon Jul 5 16:35:57 CEST 2010*

Dear Gmsh users, dear developers,
Is it possible to compute a scalar product of complex vector fields contained
in different views with Gmsh ?
In fact, I would like to compute a magnetic energy density wm as the volume
integral of the scalar product of two fields coming from different
frequency-domain FE resolutions, 1 and 2, as follows :
wm_1,2=1/2 * Int (b_1*conj(h_2)) dv,
where b_1 and h_2 are complex vector fields.
I have seen that the plugin "Integrate" can be used for the integration, but
what plugin should I use for the scalar product between the two complex
vector fields, including the conjugate complex operation ? Maybe
the "Evaluate" plugin is appropriate for this task, but I can not figure out
how to do it, since different "Time-step"-s as well as
different "Component"-s are involved at the same time.
Thank you very much for your help !
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Ir. Zacharie De Grève
Aspirant FNRS
Service de Génie Electrique
Faculté Polytechnique de Mons - UMons
Bd Dolez, 31
BE - 7000 Mons
Belgique
Tél : +32 65 374125
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