In addition to the generic FME feature attributes that FME Workbench adds to all features (see About Feature Attributes), this format adds the format-specific attributes described in this section.
The following FME attributes describe properties of the netCDF dataset.
| Attribute Name | Contents |
|
netcdf_type |
This will always be netcdf_raster. |
|
netcdf_format |
Format of the netCDF dataset. Valid values are CLASSIC and 64_BIT_OFFSET. This is a reader attribute. |
|
netcdf_subdataset_name |
When this is present on a feature, the feature is a subdataset. This attribute shows the name of the subdataset. This is a reader attribute. |
|
netcdf_subdataset_description |
When this is present on a feature, the feature is a subdataset. This attribute gives a description of the subdataset. This is a reader attribute. |
The following FME attributes are stored as global attributes in the netCDF dataset.
| Attribute Name | Contents |
|---|---|
| netcdf_comment | Miscellaneous information about the data or methods used to produce it. |
| netcdf_conventions | Name of the conventions followed by the dataset. By default, the writer will write CF-1.5 conventions. Note that specifying a different value will not necessarily make the data conform to those conventions. |
| netcdf_history | List of the applications that have modified the original data. |
| netcdf_institution | Where the original data was produced. |
| netcdf_references | References that describe the data or methods used to produce it. |
| netcdf_source | Method of production of the original data. |
| netcdf_title | Short description of the file contents. |
The following FME attributes are used to describe/define dimensions and coordinate variables in the netCDF dataset.
| Attribute Name | Contents |
|---|---|
| netcdf_coordinate_variable{}.name | Name of the dimension / coordinate variable. |
| netcdf_coordinate_variable{}.type | Type of the coordinate variable. Valid values are byte, short, int, float, double. |
| netcdf_coordinate_variable{}.axis | Identifies latitude, longitude, vertical, or time axes. |
| netcdf_coordinate_variable{}.bounds |
Identifies a boundary variable. This is a reader attribute. |
| netcdf_coordinate_variable{}.calendar | Calendar used for encoding time axes. |
| netcdf_coordinate_variable{}.compress |
Records dimensions which have been compressed by gathering. This is a reader attribute. |
| netcdf_coordinate_variable{}.climatology |
Identifies a climatology variable. This is a reader attribute. |
| netcdf_coordinate_variable{}.formula_terms |
Identifies variables that correspond to the terms in a formula. This is a reader attribute. |
| netcdf_coordinate_variable{}.leap_month | Specifies which month is lengthened by a day in leap years for a user defined calendar. |
| netcdf_coordinate_variable{}.leap_year | Provides an example of a leap year for a user defined calendar. It is assumed that all years that differ from this year by a multiple of four are also leap years. |
| netcdf_coordinate_variable{}.long_name | A descriptive name that indicates a variable's content. This name is not standardized. |
| netcdf_coordinate_variable{}.month_lengths{} | Specifies the length of each month in a non-leap year for a user defined calendar. |
| netcdf_coordinate_variable{}.positive | Direction of increasing vertical coordinate value. |
| netcdf_coordinate_variable{}.standard_name | A standard name that references a description of a variable's content in the standard name table. |
| netcdf_coordinate_variable{}.units | Units of a variable's content. |
| netcdf_coordinate_variable{}.valid_max | Largest valid value of a variable. |
| netcdf_coordinate_variable{}.valid_min | Smallest valid value of a variable. |
| netcdf_coordinate_variable{}.valid_range{} | Smallest and largest valid values of a variable. |
|
netcdf_coordinate_variable{}.user_attrs{}.name netcdf_coordinate_variable{}.user_attrs{}.type netcdf_coordinate_variable{}.user_attrs{}.value |
Together these three values specify an attribute that will be connected to a coordinate variable. Name specifies the name of the attribute. Type specifies the type of the attribute. Valid values are char, byte, short, int, float, double. Value specifies the value of the attribute. |
| netcdf_band{}.coordinate_variable{} |
Specifies the value for each "extra" (i.e. non-x/y) coordinate variable corresponding to each band. For example, suppose a data variable depends on two extra dimensions: {year, month }, where year has values {2000, 2001} and month has values {1, 2, ..., 12}. Then the raster will have 24 bands, and the values for this attribute will be as follows: netcdf_band{0}.coordinate_variable{0} = 2000 netcdf_band{0}.coordinate_variable{1} = 1 netcdf_band{1}.coordinate_variable{0} = 2000 netcdf_band{1}.coordinate_variable{1} = 2 ... netcdf_band{11}.coordinate_variable{0} = 2000 netcdf_band{11}.coordinate_variable{1} = 12 netcdf_band{12}.coordinate_variable{0} = 2001 netcdf_band{12}.coordinate_variable{1} = 1 ... netcdf_band{23}.coordinate_variable{0} = 2001 netcdf_band{23}.coordinate_variable{1} = 12 |
The following FME attributes are used to describe/define the data variable in the netCDF dataset.
| Attribute Name | Contents |
|---|---|
| netcdf_data_variable.name | Name of the data variable. |
| netcdf_data_variable.add_offset | Specifies an offset to be added to each value for a variable. |
| netcdf_data_variable.ancillary_variables |
Identifies a variable that contains closely associated data, e.g., the measurement uncertainties of instrument data. This is a reader attribute. |
| netcdf_data_variable.cell_measures |
Identifies variables that contain cell areas or volumes. This is a reader attribute. |
| netcdf_data_variable.cell_methods |
Records the method used to derive data that represents cell values. This is a reader attribute. |
| netcdf_data_variable.comment | Miscellaneous information about the data or methods used to produce it. |
| netcdf_data_variable.coordinates |
Identifies auxiliary coordinate variables, label variables, and alternate coordinate variables. This is a reader attribute. |
| netcdf_data_variable.flag_masks{} | Provides a list of bit fields expressing Boolean or enumerated flags. |
| netcdf_data_variable.flag_meanings | Use in conjunction with flag_values to provide descriptive words or phrases for each flag value. If multi-word phrases are used to describe the flag values, then the words within a phrase should be connected with underscores. |
| netcdf_data_variable.flag_values{} | Provides a list of the flag values. Use in conjunction with flag_meanings. |
| netcdf_data_variable.grid_mapping | Identifies the name of a variable that defines a grid mapping. |
| netcdf_data_variable.institution | Where the original data was produced. |
| netcdf_data_variable.long_name | A descriptive name that indicates a variable's content. This name is not standardized. |
| netcdf_data_variable.references | References that describe the data or methods used to produce it. |
| netcdf_data_variable.scale_factor | Specifies an offset to be multiplied with each value for a variable. |
| netcdf_data_variable.source | Method of production of the original data. |
| netcdf_data_variable.standard_error_multiplier | If a data variable with a standard_name modifier of standard_error has this attribute, it indicates that the values are the stated multiple of one standard error. |
| netcdf_data_variable.standard_name | A standard name that references a description of a variable's content in the standard name table. |
| netcdf_data_variable.units | Units of a variable's content. |
| netcdf_data_variable.valid_max | Largest valid value of a variable. |
| netcdf_data_variable.valid_min | Smallest valid value of a variable. |
| netcdf_data_variable.valid_range{} | Smallest and largest valid values of a variable. |
|
netcdf_data_variable.user_attrs{}.name netcdf_data_variable.user_attrs{}.type netcdf_data_variable.user_attrs{}.value |
Together these three values specify an attribute that will be connected to the data variable. Name specifies the name of the attribute. Type specifies the type of the attribute. Valid values are char, byte, short, int, float, double. Value specifies the value of the attribute. |