OP Graph
a post-processing package for SWAN

The Swan Support Package contains an executable OPGraph program, but only for single-processor execution on the Windows platform. Users who need a version for Unix or a multi-processor version, can contact us to obtain the source code of OPGraph. It is appreciated if such users make their executable available to others.

OPGraph accepts tables in various formats, among them the 1-d and 2-d spectral files produced by SWAN. This enables SWAN users to make pictures of source terms. This is essential for wave researchers but also for model engineers who need detailed insight into the physics in order to explain why certain results were obtained.
Since many different formats are accepted by OPGraph observed values can easily be included in the graphs showing SWAN results.

OPGraph also shows 2-d spectra in colored graphs. The figure shows a spectrum of the quadruplet interaction term in one of the locations in the Haringvliet area. SWAN itself can produce similar pictures of the spectral energy density, but OPGraph can also make them for source terms thus enabling the user to get deeper insight in the physics. OPGraph uses as input the output of source terms that SWAN-DHH can make for test points.

OPGraph is able to use logarithmic axes, and it allows the user to add various kinds of texts. It has a powerful mechanism to repeat codes if more than one similar quantities have to be shown.

OPGraph not only makes graphs of quantities read directly from files; it can also make calculations with these quantities. Expressions in OPGraph can involve the usual algebraic operations, but also many transcendental functions. Users can generate analytical solutions to compare numerical results with, or they can make graphs of e.g. the difference between two numerical results.