1 1 GfsSimulation GfsBox GfsGEdge {} {
    # use a non-uniformly-stretched metric in the y-direction
    # the grid points are denser close to the wall
    Metric M {
	y = tanh(4.*ry)/tanh(4./2.)/2.
    }
    
    Refine LEVEL
    # use backward Euler to avoid Crank-Nicholson oscillations in time
    SourceViscosity 1. { beta = 1 }
    Source U 1
    # add a transverse source term to also test hydrostatic balance
    Source V 1

    EventStop { istep = 1 } U 1e-6 DU
    ProjectionParams { tolerance = 1e-6 }
    ApproxProjectionParams { tolerance = 1e-6 }
    OutputErrorNorm { start = end } { awk '{print LEVEL,$5,$7,$9}' } { v = U } { 
        s = 1./2.*(1./4 - y*y) 
    }
}
GfsBox {
    bottom = Boundary {
        BcDirichlet U 0 
    }
    top = Boundary {
        BcDirichlet U 0 
    }
}
1 1 right