Input and Output Formats

Text tables

merge1d and ssh1d accept ordinary text tables, in addition to NetCDF series. The first column is the coordinate and subsequent columns are fields. A participating set of tables must have the same number of field columns and strictly increasing coordinates after input scaling. Scaling does not reorder table rows. merge1d cannot use both text and NetCDF sources in a single run.

NetCDF variables

GQ reads single and multiparameter NetCDF files. Compatible fields share coordinate dimensions. Though the names of equivalent fields may differ between source files. Coordinate variables are identified through standard axis metadata and conventional x, y, and z names.

merge2d NetCDF inputs can be ordinary grids or selected layers from three-dimensional cubes. Three-dimensional model variables may store their dimensions in any order when the coordinate relationship is unambiguous. However, GQ output cubes use a (z,y,x) order.

When SSH application changes a model lattice through -R, -I, or -T, scalar ancillary variables in the NetCDF file are unchanged. Unselected variables that depend on a changed coordinate are omitted because they no longer match the output lattice.

Output variables

The merge modules may append a shared variable named weight or write only that variable. Its long_name is merging weight, its units are 1, and its range is from zero to one.

The SSH modules use fractional perturbations. In application mode, selected model values are multiplied by 1 + epsilon. A taper requested for output is also called weight, with long_name set to heterogeneity taper weight.

GQ writes missing output values as NaN. See Missing Values.