Stage_VS

{  STAGE_VS.PDE  }

{

   This problem is a modification of Stages.pde in which the VERSUS qualifier

   has been used to change the abcissa of the history plot.

}

title 'Staged Problem - Versus parameter'

select

    stages=3

    errlim = staged(0.01, 0.001, 0.0005)

Variables

    u

definitions

    scale = staged(1, 2, 4, 8)                { extra value ignored }

    a = 1/scale

Initial values

    u = 1 - (x-1)**2 - (y-1)**2

equations

    div(a*grad(u)) + scale*u*dx(u) +4 = 0;

boundaries

    region 1

       start(0,0)

       value(u)=0        line to (2,0) to (2,2) to (0,2) to close

monitors

    contour(u)

plots

    surface(u) report scale as "Scale"

    contour(u) report scale as "Scale"

histories

    history(integral(u)) versus scale

end