Expanded NetCDF support: Difference between revisions
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== Use Cases == | == Use Cases == | ||
=== Files that use the | === NC4.1: Files that use the NetCDF4 Classic model === | ||
File that conform to the '''NC_CLASSIC_MODEL''' data model as documented by Unidata will open and work without error. | |||
Although the files use only data model features found in the netCDF 3 data model/API, using the netCDF 4 API will enable chunking and internal compression ''if'' the files in question were written that way. | Although the files use only data model features found in the netCDF 3 data model/API, using the netCDF 4 API will enable chunking and internal compression ''if'' the files in question were written that way. | ||
To be safe, the software that writes the files should use the ''' | To be safe, the software that writes the files should use the '''NC_CLASSIC_MODEL''' when it makes/modifies the file(s). | ||
=== Files that use some new features === | === NC4.2: Files that use some new features === | ||
=== Files that use all new features === | The specific features that will be supported are: | ||
* All of the [http://www.unidata.ucar.edu/software/netcdf/docs/netcdf/External-Types.html#External-Types External Data Types] ''except'' the '''int64''' and '''uint64'''. | |||
* Enum: Supported by using an int and a set of attributes | |||
* Opaque: Supported by using a Byte array and an attribute indicating that the data are to be treated as an atomic entity | |||
* Groups: Encoded using slash ('''/''') characters in variable names in a way that is compatible with the convention established by The HDF Group and NASA for HDF5 files. | |||
=== NC4.3: Files that use (potentially) all new features === | |||
These will fail with an error message indicating they are not supported along with the specific feature that caused the failure. | These will fail with an error message indicating they are not supported along with the specific feature that caused the failure. | ||
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Unsupported NetCDF4 model/API features are: | Unsupported NetCDF4 model/API features are: | ||
* User defined types | * User defined types | ||
* Multiple unlimited dimensions | |||
* Int64 and Unsigned Int64 [http://www.unidata.ucar.edu/software/netcdf/docs/netcdf/External-Types.html#External-Types External Data Types] | * Int64 and Unsigned Int64 [http://www.unidata.ucar.edu/software/netcdf/docs/netcdf/External-Types.html#External-Types External Data Types] | ||
Revision as of 23:24, 13 January 2011
Expanded NetCDF Support
Use Cases
NC4.1: Files that use the NetCDF4 Classic model
File that conform to the NC_CLASSIC_MODEL data model as documented by Unidata will open and work without error.
Although the files use only data model features found in the netCDF 3 data model/API, using the netCDF 4 API will enable chunking and internal compression if the files in question were written that way.
To be safe, the software that writes the files should use the NC_CLASSIC_MODEL when it makes/modifies the file(s).
NC4.2: Files that use some new features
The specific features that will be supported are:
- All of the External Data Types except the int64 and uint64.
- Enum: Supported by using an int and a set of attributes
- Opaque: Supported by using a Byte array and an attribute indicating that the data are to be treated as an atomic entity
- Groups: Encoded using slash (/) characters in variable names in a way that is compatible with the convention established by The HDF Group and NASA for HDF5 files.
NC4.3: Files that use (potentially) all new features
These will fail with an error message indicating they are not supported along with the specific feature that caused the failure.
Unsupported NetCDF4 model/API features are:
- User defined types
- Multiple unlimited dimensions
- Int64 and Unsigned Int64 External Data Types
