compute

this is ever so slightly faster (for barotropic only), but why add the complication?

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Discussion

PVbar = self.PVA0 .* wvt.A0; PVx = wvt.transformToSpatialDomainWithF(A0=sqrt(-1)shiftdim(wvt.k,-1).PVbar); PVy = wvt.transformToSpatialDomainWithF(A0=sqrt(-1)shiftdim(wvt.l,-1).PVbar);