Export to ASEG-GDF

Use the Database > Export > ASEG-GDF menu option (EXPASEG GX) to export data to an ASEG-GDF file format with full support of projection. Either displayed data channels or all data channels may be exported, and the displayed line, selected lines or all lines may be exported. If the output file(s) already exist, they will be overwritten.

Export to ASEG-GDF dialog options

ASEG-GDF DEFN file	Sselect the ASEG-GDF header file containing the data formats (*.dfn). Script Parameter: EXPASEG.DEFN
ASEG-GDF data file	Select the ASEG-GDF data file (*.dat) that contains the data, one record per line. Script Parameter: EXPASEG.DATA
ASEG-GDF description file	Select the ASEG-GDF description file (*.des) that contains the identifier COMM on every line. Script Parameter: EXPASEG.DESC
ASEG-GDF projection file	Select the ASEG-GDF projection file (*.prj) that contains the projection parameters. Script Parameter: EXPASEG.PROJ
Channel with projection	Select the channel with projection from the list of the current database channels. Script Parameter: EXPASEG.CHPROJ
Channels to save	Select from one of the options below, the channels to save: Displayed channels All database channels Script Parameter: EXPASEG.CHAN
Lines/Groups to save	Select from one of the options below, the lines/groups to save: Selected lines Displayed line All lines Script Parameter: EXPASEG.LINE

Application Notes

If only the DEFN file name is given, then the Data file name is assumed to have the same name, and the extension ".dat". If only the DATA file name is given, then the DEFN file name is assumed to have the same name, and the extension ".dfn".

In the output file, the first parameter output is the channel number. For lines, this corresponds to the line number in Oasis montaj. For groups, a "0" is written because groups do not generally have numbers for names.

If both groups and lines are present in a database the behaviour is more complicated, because groups tend to have channels unique to themselves.

The "Displayed Line" option: This works for a single group or lines, and only the displayed group or line is output.

The "Selected Lines" option: If there are both lines and groups selected, only lines will be output. If there are only groups selected, then only the first group will be output.

The "All Lines" option: If there are both lines and groups present, then only the first group will be output.

This GX supports array channel exports. Dummy values are automatically converted to ASEG-GDF null values, determined from the output format. The output format width and number of decimals are derived from the channel settings. The format corresponds to the FORTRAN "F" notation.

ASEG-GDF Description File (optional)

The ASEG-GDF description file (*.des or *.txt) is an ASCII text file with no preset format, except it contains the identifier "COMM" on every line. By default, the browse window shows files with the ".txt" extension.

Projection Parameters

The projection parameters are saved according to ‘The ASEG-GDF2 Standard for Point Located Data, Draft 1.0’. However, this standard did not specify how datum transformation parameters should be stored. In order to save all the parameters, a new key word TRNS is used, similar to the key word PROJ.