/usr/share/metview/etc/NetcdfPlusRules is in metview-data 4.8.0-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 | %if NETCDF_PLOT_TYPE = GEO_POINTS %then
     %unset NETCDF_X_VARIABLE
     %unset NETCDF_Y_VARIABLE
     %unset NETCDF_X_POSITION_VARIABLE
     %unset NETCDF_Y_POSITION_VARIABLE
     %unset NETCDF_X2_VARIABLE
     %unset NETCDF_Y2_VARIABLE
     %unset NETCDF_X_COMPONENT_VARIABLE
     %unset NETCDF_Y_COMPONENT_VARIABLE
     %unset NETCDF_POSITION_TYPE
%if NETCDF_PLOT_TYPE = GEO_VECTORS %then
     %unset NETCDF_X_VARIABLE
     %unset NETCDF_Y_VARIABLE
     %unset NETCDF_X_POSITION_VARIABLE
     %unset NETCDF_Y_POSITION_VARIABLE
     %unset NETCDF_X2_VARIABLE
     %unset NETCDF_Y2_VARIABLE
     %unset NETCDF_VALUE_VARIABLE
     %unset NETCDF_POSITION_TYPE
%if NETCDF_PLOT_TYPE = GEO_MATRIX %then
     %unset NETCDF_X_VARIABLE
     %unset NETCDF_Y_VARIABLE
     %unset NETCDF_X_POSITION_VARIABLE
     %unset NETCDF_Y_POSITION_VARIABLE
%if NETCDF_PLOT_TYPE = XY_POINTS %then
     %unset NETCDF_LATITUDE_VARIABLE
     %unset NETCDF_LONGITUDE_VARIABLE
     %unset NETCDF_X_COMPONENT_VARIABLE
     %unset NETCDF_Y_COMPONENT_VARIABLE
     %unset NETCDF_X_POSITION_VARIABLE
     %unset NETCDF_Y_POSITION_VARIABLE
     %unset NETCDF_POSITION_TYPE
%if NETCDF_PLOT_TYPE = XY_VECTORS %then
     %unset NETCDF_LATITUDE_VARIABLE
     %unset NETCDF_LONGITUDE_VARIABLE
     %unset NETCDF_X_VARIABLE
     %unset NETCDF_Y_VARIABLE
     %unset NETCDF_X2_VARIABLE
     %unset NETCDF_Y2_VARIABLE
     %unset NETCDF_VALUE_VARIABLE
     %unset NETCDF_POSITION_TYPE
%if NETCDF_PLOT_TYPE = XY_MATRIX %then
     %unset NETCDF_LATITUDE_VARIABLE
     %unset NETCDF_LONGITUDE_VARIABLE
     %unset NETCDF_X_POSITION_VARIABLE
     %unset NETCDF_Y_POSITION_VARIABLE
 |