private static boolean isProximityTable(NativeTable table) {
        return (table.getType().equals(NativeTable.Type.PROXIMITY) ||
                table.getType().equals(NativeTable.Type.REVERSE_PROXIMITY));
    }
The rank settings of a field used for native rank features.

@author geirst
config-model/src/main/java/com/yahoo/schema/derived/FieldRankSettings.java