This function reads data into the data buffer from a subsetted region as defined by EOS_GD_DEFBOXREGION.
Result = EOS_GD_EXTRACTREGION(gridID, regionID, fieldname, buffer)
Returns SUCCEED (0) if successful and FAIL (-1) otherwise.
Grid id (long) returned by EOS_GD_CREATE or EOS_GD_ATTACH.
Region or period id (long) returned by EOS_GD_DEFBOXREGION.
Field to subset (string).
A named variable that will contain the data Buffer.
In this example, we extract data from the "Temperature" field from the region defined in EOS_GD_DEFBOXREGION. The size of the subsetted region for the field is given by the EOS_GD_REGIONINFO routine.
status = EOS_GD_EXTRACTREGION(EOS_GD_id, regionID, $ "Temperature", datbuf32)