Datum Mappings

This reference table maps the datum identification numbers used in the coordinate system definition section of MapInfo® Interchange Format (MIF) files to the corresponding datums as defined in the OCRIS reference data.

The datum number appears in the CoordSys line of the MIF file header, viz:

The number 116 appearing in the MIF header corresponds to the GDA94 datum as defined in the OCRIS reference data.

Field	Description
Datum number	Datum reference number as used in the MIF file header
Description	A short description of the datum
Mapped datum name	Name of the corresponding datum defined in OCRIS

Distance Units

This is a reference table for the units of measurement used in MapInfo® Interchange Format (MIF) file headers.

Coordinates are usually reported in metres, so no conversion is necessary. However, in cases where other units are specified, all coordinates will be converted to metres on import, using the specified metric conversion factor. The following example shows the setup for "yards".

Field	Description
Unit number	Unique database key used for this unit
Display text	Text used as an identifier in MIF file headers
ToMetres	Factor to convert the MIF units to metres by multiplication