When applying the sounding datum height(s) (distance from the ellipsoid to the sounding datum) to a track line, these methods may be used:
• apply a single height to a track line, or,
• apply a selected surface layer, with a set elevation attribute, or,
• apply a gridded binary (.bin) file, or,
• apply a sounding datum model file in ASCII format, that contains a grid of sounding datum heights (with either Ground or Geographic coordinates).
Sounding datum heights can be applied for Computing GPS tide.
ASCII datum model files do not need to follow a specific format or have a specific extension. However, when an ASCII datum file is selected as the datum model, a *.info must also be opened to control the parsing of the ASCII data. (See INFO file.)
As well, a coordinate system must be selected to identify the position information in the ASCII file.
XYZ and BIN files used in the Compute GPS Tide function can be opened as background data.
When an XYZ is opened in HIPS, the selection of *.info and coordinate system is saved in a file with the same name of the .xyz file, but with an “_rxl” suffix.
For example, if you select “mydata.xyz,” then “mydata.xyz_rxl” will be created in the same directory as the original XYZ file. If you open the same .xyz file again, the information from this file is automatically used.