[Nek5000-users] Averaging in the y-z plane

[nek5000-users at lists.mcs.anl.gov]

Hi David,

Without digging into the context (for verification), symmetry 
would lead me to write:

       xx = (1.-zgm1(k,1))/2.  ! = 1 for k=1, = 0 for k=nx1
       aa = xx*area(i,1,2,e) + (1-xx)*area(i,1,4,e)  ! wgtd jacobian


I'm not certain of the "k"  (one would normally use "i"... but
it is being used for the area() counter).

Does this get you started?   I can try to look in more detail
if you need.

Best regards,

Paul


On Wed, 27 Jul 2011, nek5000-users at lists.mcs.anl.gov wrote:

> Hi Neks,
>
> I am trying to write a routine that averages over the y-z plane, yielding an
> array that varies in the x dimension.  I have seen the planar_average_z
> routine in navier5.f that averages over x-y, and I have a planar_average_y
> routine that Paul sent me.  So, I am trying to write planar_average_x.  I
> have been able to proceed by analogy, except for the two lines in which the
> weighting coefficients are computed.
>
> I planar_average_z,
>
> yy = (1.-zgm1(j,2))/2.  ! = 1 for j=1, = 0 for j=ny1
> aa = yy*area(i,1,1,e) + (1-yy)*area(i,1,3,e)  ! wgtd jacobian, fc 1&3
>
> In planar_aveage_y,
>
> zz = (1.-zgm1(k,3))/2.  ! = 1 for k=1, = 0 for k=nz1
> aa = zz*area(i,1,5,e) + (1-zz)*area(i,1,6,e)  ! wgtd jacobian
>
> Can someone tell me what the analogous lines would be for planar_average_x,
> as well as what the area tensor is?
>
> Thanks very much,
>
> David
>