UTL-NCF

Structure of Blocks

FOR EACH SIMULATION

    BEGIN OPTIONS
      [WKT <wkt>]
      [DEFLATE <deflate>]
      [SHUFFLE]
      [CHUNK_TIME <chunk_time>]
      [CHUNK_FACE <chunk_face>]
      [CHUNK_Z <chunk_z>]
      [CHUNK_Y <chunk_y>]
      [CHUNK_X <chunk_x>]
      [MODFLOW6_ATTR_OFF]
    END OPTIONS
    BEGIN DIMENSIONS
      [NCPL <ncpl>]
    END DIMENSIONS
    BEGIN GRIDDATA
      [LATITUDE
            <latitude(ncpl)> -- READARRAY]
      [LONGITUDE
            <longitude(ncpl)> -- READARRAY]
    END GRIDDATA

Explanation of Variables

Block: OPTIONS

  • wkt is the coordinate reference system (CRS) well-known text (WKT) string.

  • deflate is the variable deflate level (0=min, 9=max) in the netcdf file. Defining this parameter activates per-variable compression at the level specified.

  • SHUFFLE is the keyword used to turn on the netcdf variable shuffle filter when the deflate option is also set. The shuffle filter has the effect of storing the first byte of all of a variable’s values in a chunk contiguously, followed by all the second bytes, etc. This can be an optimization for compression with certain types of data.

  • chunk_time is the keyword used to provide a data chunk size for the time dimension in a NETCDF_MESH2D or NETCDF_STRUCTURED output file. Must be used in combination with the the chunk_face parameter (NETCDF_MESH2D) or the chunk_z, chunk_y, and chunk_x parameter set (NETCDF_STRUCTURED) to have an effect.

  • chunk_face is the keyword used to provide a data chunk size for the face dimension in a NETCDF_MESH2D output file. Must be used in combination with the the chunk_time parameter to have an effect.

  • chunk_z is the keyword used to provide a data chunk size for the z dimension in a NETCDF_STRUCTURED output file. Must be used in combination with the the chunk_time, chunk_x and chunk_y parameter set to have an effect.

  • chunk_y is the keyword used to provide a data chunk size for the y dimension in a NETCDF_STRUCTURED output file. Must be used in combination with the the chunk_time, chunk_x and chunk_z parameter set to have an effect.

  • chunk_x is the keyword used to provide a data chunk size for the x dimension in a NETCDF_STRUCTURED output file. Must be used in combination with the the chunk_time, chunk_y and chunk_z parameter set to have an effect.

  • MODFLOW6_ATTR_OFF is the keyword used to turn off internal input tagging in the model netcdf file. Tagging adds internal modflow 6 attribute(s) to variables which facilitate identification. Currently this applies to gridded arrays.

Block: DIMENSIONS

  • ncpl is the number of cells in a projected plane layer.

Block: GRIDDATA

  • latitude cell center latitude.

  • longitude cell center longitude.

Example Input File

    BEGIN OPTIONS
      DEFLATE 5
      SHUFFLE
      CHUNK_TIME 10
      CHUNK_FACE 19690
      WKT 'PROJCS["NAD_1983_UTM_Zone_14N",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["
    GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transver
    se_Mercator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-99.
    0],PARAMETER["Scale_Factor",0.9996],PARAMETER["Latitude_Of_Origin",0.0],UNIT["Meter",1.0]]'
    END OPTIONS