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Companion Tools

The EnOI-suite data assimilation software suite includes principally a data assimilation code but also some useful companion tools for ensemble generation and other features (pseudo-observations generation).

This page provide basic information for use of these companion tools.

Unifying topography products (normalize)

normalize companion tool makes GRD-formatted topography data file similar, using the same convention for longitude [-180:180].

normalize f1.grd [f2.grd f3.grd f4.grd...]


  • f1. grd: GRD-formatted topography data file
  • ...

Output file(s): GRD-formatted file(s) f1.normalize.grd, ...

Diagnosing topography products differences (celerity)

celerity companion tool provides statistics on normalized topography data products. Spatial sampling of statistic grids is adjusted on the first product spatial grid.

celerity f1.grd f2.grd [f3.grd f4.grd...]


  • f1.grd: GRD-formatted normalized topography data file;
  • f2.grd: GRD-formatted normalized topography data file;
  • ...

Output files: GRD-formatted statistics files min.grd, max.grd, mean.grd, std.grd

Generating perturbated topography solutions (compose)

compose companion tool creates perturbated topography solutions based on differences between a set of topography products and a preferred topography product.Perturbated topography solution is defined locally as the sum of the preferred topography product and the weighted sum of the other topography products, as below:

compose f1.grd f2.grd [f3.grd f4.grd...] N


  • f1.grd: GRD-formatted normalized topography data file;
  • f2.grd: GRD-formatted normalized topography data file;
  • ...
  • N: number of requested perturbated topography solutions


Output file(s): a set of N GRD-formatted normalized topography data files (compo_*.grd)

Generating perturbated open bondary conditions (compose_obc)

compose_obc companion tool creates OBC-formatted perturbated open boundary conditions based on statistical differences between a set of tidal model at open boundaries of the model.

compose_obc -i <nodefile> -n <val> f1.WAVE.bmg f2.WAVE.bmg [f3.WAVE.bmg f4.WAVE.bmg...]


  • nodefile: open boundaries locations file (e.g. tides.input ou WAVE.obc)
  • val: number of requested perturbated open boundaries elevations information
  • f1.WAVE.bmg: tidal solution data file for constituent WAVE (atlas #1)
  • f2.WAVE.bmg: tidal solution data file for constituent WAVE (atlas #2)
  • ...


Output file(s): a set of val OBC-formatted open boundaries tidal elevation values for constituent WAVE (WAVE_*.obc)

Generating synthetic observations (synthetic)

synthetic companion tool create pseudo-observations interpolated from a reference simulation and regularly sampled onto a cartesian grid.

synthetic <config>


Output file(s): pseudo observations for requested tidal constituents (*pseudo-obs.obs)