eccodes 2.47.0

Python interface to the ecCodes GRIB and BUFR decoder/encoder

Python 3 interface to decode and encode GRIB and BUFR files via the ECMWF ecCodes library.

Features:

• reads and writes GRIB 1 and 2 files,

• reads and writes BUFR 3 and 4 files,

• supports all modern versions of Python and PyPy3,

• works on most Linux distributions and MacOS, the ecCodes C-library is the only system dependency,

• PyPI package can be installed without compiling, at the cost of being twice as slow as the original ecCodes module,

• an optional compile step makes the code as fast as the original module but it needs the recommended (the most up-to-date) version of ecCodes.

Limitations:

• Microsoft Windows support is untested.

Installation

From version 2.43.0, the ecCodes Python bindings on PyPi will depend on the PyPi package ‘eccodeslib’ on Linux and MacOS. This package provides the binary ecCodes library. On Windows, the ecCodes Python bindings will continue to directly provide the ecCodes binary library without a dependency on eccodeslib. See below for details.

Installation from PyPI

The package can be installed from PyPI with:

$ pip install eccodes

This installation will, by default, include the ecCodes binary library (either supplied by the ‘eccodes’ package on Windows, or via the ‘eccodeslib’ package on Linux and MacOS), meaning that no external ecCodes binary library is required.

Bypassing the provided binary library

Linux and MacOS

If you have an external ecCodes binary library that you wish to use, consult the documentation of the findlibs package, which is used by the ecCodes Python bindings to locate the binary library. This allows the use of environment variables to refine the search algorithm.

Windows

If you have an external ecCodes binary library that you wish to use, set the following environment variable before you import eccodes:

$ export ECCODES_PYTHON_USE_FINDLIBS=1

If this is set, the ecCodes’ Python bindings will use the findlibs package to locate the binary library.

You may also install a version of ecCodes’ Python interface that does not include a binary library at all, in which case the findlibs mechanism will be used as before:

$ pip install eccodes --no-binary eccodes

See also ‘Debugging the library search’, below.

Installation from conda

ecCodes’ Python bindings can be installed from the conda-forge channel with:

$ conda install -c conda-forge python-eccodes

This will install the Python bindings (python-eccodes) and also the ecCodes binary library (eccodes) on which they depend.

System dependencies

The Python module depends on the ECMWF ecCodes binary library. From version 2.37.0, this library is supplied with the Python module on both PyPi and conda, as described above. If you wish to install and use a separate binary library (see above), it must be installed on the system and accessible as a shared library.

On a MacOS with HomeBrew use:

$ brew install eccodes

Or if you manage binary packages with Conda but use Python bindings from elsewhere, use:

$ conda install -c conda-forge eccodes

As an alternative you may install the official source distribution by following the instructions at https://confluence.ecmwf.int/display/ECC/ecCodes+installation

You may run a simple selfcheck command to ensure that your system is set up correctly:

$ python -m eccodes selfcheck
Found: ecCodes v2.42.0.
Your system is ready.

Debugging the library search

In order to gain insights into the search for the binary library, set the following environment variable before importing eccodes:

$ export ECCODES_PYTHON_TRACE_LIB_SEARCH=1

Usage

See examples of how to use the high-level BUFR interface: BUFR_Tour.md and BUFR_Snippets.md.

Refer to the ecCodes documentation pages for usage.

Experimental features

Fast bindings

To test the much faster CFFI API level, out-of-line mode you need the ecCodes header files. Then you need to clone the repo in the same folder as your ecCodes source tree, make a pip development install and custom compile the binary bindings:

$ git clone https://github.com/ecmwf/eccodes-python
$ cd eccodes-python
$ pip install -e .
$ python builder.py

To revert back to ABI level, in-line mode just remove the compiled bindings:

$ rm gribapi/_bindings.*

Project resources

Development	https://github.com/ecmwf/eccodes-python
Download	https://pypi.org/project/eccodes

Contributing

The main repository is hosted on GitHub, testing, bug reports and contributions are highly welcomed and appreciated:

https://github.com/ecmwf/eccodes-python

Please see the CONTRIBUTING.rst document for the best way to help.

Maintainers:

• Shahram Najm - ECMWF

• Eugen Betke - ECMWF

Contributors:

• Iain Russell - ECMWF

• Alessandro Amici - B-Open

See also the list of other contributors who participated in this project.

License

© Copyright 2017- ECMWF.

This software is licensed under the terms of the Apache Licence Version 2.0 which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.

In applying this licence, ECMWF does not waive the privileges and immunities granted to it by virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.

Changelog for eccodes-python

2.47.0 (2026-04-21)

• Bump pygments from 2.15.0 to 2.20.0 in /ci (#164)

• Bump requests from 2.32.4 to 2.33.0 in /ci (#163)

2.46.0 (2026-02-24)

• ECC-2219: High-level BUFR interface: set method not working for data keys

• ECC-2220: Fix inadvertent string truncation in uncompressed BUFR messages

• Fix path to BUFR md files

• Add support for Python version 3.14

2.45.0 (2025-01-16)

• GitHub issue 372: Option “–no-binary” does not work See: #372.

• GitHub issue 145: test run fails See: #145.

2.44.0 (2025-10-03)

• ECC-2102: Improved high-level interface for BUFR

• ECC-2108: Implement a way of switching off error output to stderr

• GitHub pull request #129: Update MemoryReader to read more than one field

2.43.0 (2025-07-24)

• ECC-2106: Use eccodeslib instead of own-built binaries

2.42.0 (2025-06-25)

• ECC-2081: Allow memoryview as input to codes_new_from_message

• ECC-2086: GRIB: getting the bitmap using up all the memory

• ECC-2072: high-level ‘get’ function should return default value if key is not implemented

2.41.0 (2025-04-10)

• ECC-2034: GRIB encoding: Data quality checks via the API

• GitHub pull request #124: Add basic BUFR support (high-level interface)

2.40.1 (2025-03-17)

• Update version to be the same as the ecCodes library

2.40.0 (2025-02-12)

• Update version to be the same as the ecCodes library

2.39.2 (2025-01-27)

• GitHub pull request #109: Allow setting of array in highlevel.Message.set

• Add support for Python version 3.13

2.39.1 (2024-12-10)

• Build wheel with thread-safety enabled

2.39.0 (2024-11-25)

• ECC-1972: Support Windows with binary wheel

• Update to artifact actions v4

2.38.3 (2024-10-17)

• Update version to be the same as the ecCodes library

2.38.1 (2024-09-26)

• ECC-1923: ecCodes binary wheel can affect floating-point computations in Python

2.38.0 (2024-09-25)

• ECC-1790: Add codes_get_offset

• ECC-1899: API function to allow setting debug level

• Function to query library features

2.37.0 (2024-09-09)

• bundle ecCodes binary library with the PyPi distribution, for Linux and MacOS

1.7.1 (2024-06-19)

• np.Infinity was removed in the NumPy 2.0 release

1.7.0 (2024-02-26)

• ECC-1761: Add function to extract message offsets and sizes

• ECC-1742: Add function to clone only the meta-data of a message

1.6.1 (2023-10-02)

• ECC-1693: Update minimum recommended version

• Fix flake8 warning E721

1.6.0 (2023-07-11)

• ECC-1630: Get API version as an integer

• ECC-1622: Drop Python version 3.7

• ECC-1601: GRIB: Support data values array decoded in single-precision

• ECC-1611: Add function to determine if a BUFR key is a coordinate descriptor

1.5.2 (2023-04-04)

• Add support for Python versions 3.10 and 3.11

• ECC-1555: 2D numpy array incorrectly handled

• ECC-1539: Use the ‘warnings’ library for selfcheck

• ECC-1538: Add support for CODES_TYPE_BYTES

• ECC-1524: Check values in High-level Message.set function should retrieve based on value type

• ECC-1527: Handle floats in high-level Message.set function check values

1.5.1 (2023-01-25)

• ECC-1446: Data file era5-levels-members.grib not included in released tar file

• ECC-1460: Cannot import eccodes on M1 MacBook Pro

• ECC-1505: High-level Message.set function should allow dictionary and check result

1.5.0 (2022-08-25)

• ECC-1404: Add the grib_get_gaussian_latitudes() function

• ECC-1405: Add new function: codes_any_new_from_samples

• ECC-1415: Implement a higher-level Python interface (still experimental)

• ECC-1429: Remove the file ‘eccodes/messages.py’

• GitHub pull request #62: add pypi badge

1.4.2 (2022-05-20)

• ECC-1389: Drop Python version 3.5 and 3.6

• ECC-1390: NameError: name ‘GribInternalError’ is not defined

• Add test for GRIB bitmap

1.4.1 (2022-03-03)

• ECC-1351: Support numpy.int64 in codes_set() and codes_set_long()

• ECC-1317: Data file tiggelam_cnmc_sfc.grib2 not included in released tar file

1.4.0 (2021-12-03)

• ECC-1234: Remove the experimental high-level interface

• ECC-1282: Add codes_dump()

1.3.4 (2021-08-27)

• Update documentation

1.3.3 (2021-06-21)

• ECC-1246: UnicodeDecodeError when parsing BUFR file

1.3.2 (2021-04-16)

• Restore the experimental high-level interface

1.3.1 (2021-04-16)

• Fix the recommended version

1.3.0 (2021-04-09)

• ECC-1231: Remove the experimental high-level interface

• Added the “findlibs” module

• Fix tests/test_high_level_api.py when MEMFS enabled

• ECC-1226: Python3 bindings: Typo causes AttributeError when calling codes_index_get_double

1.2.0 (2021-03-23)

• Added test for multi-field GRIBs

• Fix deprecation warning: np.float is a deprecated alias for the builtin float

• Experimental feature: grib_nearest_find

1.1.0 (2021-01-20)

• ECC-1171: Performance: Python bindings: remove assert statements

• ECC-1161: Python3 bindings: Do not raise exception on first failed attempt

• ECC-1176: Python3 bindings: float32 recognised as int instead of float

• GitHub pull request #41: Remove the apparent support for Python 2

• GitHub pull request #44: Fix CFFI crash on windows

• GitHub pull request #42: Add unit testing with GitHub actions (linux, macos and windows)

1.0.0 (2020-10-14)

• ECC-1143: CMake: Migration to ecbuild v3.4

• ECC-1133: C API: Propagate const char* for codes_index_new_from_file and codes_index_select_string

0.9.9 (2020-08-04)

• Support for ecmwflibs. An additional way to find ECMWF libraries (if available)

• ECC-1140: Segfault from invalid pointer reference in grib_set_double_array()

0.9.8 (2020-06-26)

• ECC-1110: Removed obsolete function codes_close_file()

• Provide missing argument to exceptions

• Fix codes_set_definitions_path() typo

• Fix grib_get_double_element(). Missing last argument

• Add more tests to increase coverage

• GitHub pull request #15: Add .__next__() method to eccodes.CodesFile class

• ECC-1113: Python3 bindings under Windows: codes_get_long_array returns incorrect values

• ECC-1108: Python3 bindings under Windows: use of handle causes crash

• ECC-1121: Segfault when closing GribFile if messages are closed manually

0.9.6 (2020-03-10)

• Update Copyright notices

• Function-argument type checks: Improve error message

• Fix C function calls for codes_gribex_mode_on/codes_gribex_mode_off

0.9.5 (2020-01-15)

• ECC-1029: Function-argument type-checking should be disabled by default.

  To enable these checks, export ECCODES_PYTHON_ENABLE_TYPE_CHECKS=1

• ECC-1032: Added codes_samples_path() and codes_definition_path()

• ECC-1042: Python3 interface writes integer arrays incorrectly

• ECC-794: Python3 interface: Expose the grib_get_data function

0.9.4 (2019-11-27)

• Added new function: codes_get_version_info

• ECC-753: Expose the codes_grib_nearest_find_multiple function in Python

• ECC-1007: Python3 interface for eccodes cannot write large arrays

0.9.3 (2019-10-04)

• New exception added: FunctionalityNotEnabledError

• BUFR decoding: support for multi-element constant arrays (ECC-428)

0.9.2 (2019-07-09)

• All ecCodes tests now pass

• Simplify the xx_new_from_file calls

• Fix for grib_set_string_array

• Use ECCODES_DIR to locate the library

• Remove the new-style high-level interface. It is still available in cfgrib.

0.9.1 (2019-06-06)

• codes_get_long_array and codes_get_double_array now return a np.ndarray. See: #3.

0.9.0 (2019-05-07)

• Declare the project as Beta.

0.8.0 (2019-04-08)

• First public release.