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SWASH can provide output on uniform, rectilinear grids that are independent from the input grids
and from the computational grid. In the computation with an orthogonal curvilinear computational grid,
curvilinear output grids are available in SWASH.
An output grid has to be specified by the user with an arbitrary
resolution, but it is of course wise to choose a resolution that is fine enough to show relevant spatial
details. It must be pointed out that the information on an output grid is obtained from the computational
grid by bi-linear interpolation (output always at computational time level). This implies that some
inaccuracies are introduced by this interpolation. It also implies that bottom or wind information on an
output plot has been obtained by interpolating twice: once from the input grid to the computational grid
and once from the computational grid to the output grid. If the input, computational and output grids are
identical, then no interpolation errors occur.

In the regions where the output grid does not cover the computational grid, SWASH assumes output values
equal to the corresponding exception value. For example, the default exception value for the surface elevation
is -9. The exception values of output quantities can be changed by means of the `QUANTITY`
command.

Output can be requested at regular intervals starting at a given time always at computational times.

** Next:** Boundary conditions
** Up:** Choice of grids and
** Previous:** Input grid(s) for transport
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The SWASH team 2017-04-06