Installation
Binaries and Python Bindings
Metview consists of two parts. The ‘binaries’ are the core of Metview, incorporating the user interface, the majority of the data processing code and the Macro programming language. The Python bindings sit on top of the binaries and provide a powerful Python interface to Metview’s functionality. The binaries can run standalone, and the Python bindings require the binaries.
Installing Metview’s binaries
The following package managers provide pre-built Metview binaries. The brew and conda packages are maintained by ECMWF and are generally up to date.
Homebrew
Metview’s binaries are available from Homebrew on macOS, including the M1 processors, and Linux (Linux distribution on brew exists but has not been tested). They are installed like this:
brew install metview
Once installed, Metview can be updated with this command:
brew upgrade metview
Conda
Metview’s binaries are available on conda for both Linux and macOS, including the M1 processors. From a conda environment, the following command will install Metview:
conda install metview -c conda-forge
Once installed, Metview can be updated with this command:
conda update metview -c conda-forge
There is also a batch-only version of Metview’s binaries on conda, called metview-batch. This does not include the graphical user interface and is therefore more lightweight and can be used in environments such as Binder. It does include the ability to produce graphical plots, and they must be generated as files (PNG, PDF, SVG, …) or as inline plots in Jupyter notebooks.
conda install metview-batch -c conda-forge
Community-built Binary Packages
Community-built Metview binaries for a number of Linux distributions can be found here: https://software.opensuse.org/download.html?project=home%3ASStepke&package=Metview
From Ubuntu 16.04, Metview is available from the standard repositories and can be installed like this:
sudo apt-get install metview
These packages are not maintained by ECMWF, so any issues with installation should be reported to their maintainers.
Installing Metview’s python interface
Metview’s Python interface is installed separately. Note: Metview’s Python interface requires the binaries to be present.
Conda
If you are working in a conda environment, then it is recommended to install via conda:
conda install metview-python -c conda-forge
Metview Source Releases
See the Change History for details of each release. The source of each Metview version can be found on the Releases page.
To build Metview and its ECMWF dependencies in one go, try The Metview Source Bundle.
Metview’s Python bindings are available on github: https://github.com/ecmwf/metview-python
Tips on installing Metview into environments
These small guides are not intended to replace the official documentation on how to create and used conda environments and virtualenvs, they are just a quick suggested way to get started!
Conda
Conda allows you to install binaries and Python packages into the same environment. With conda, it’s almost always neater to install software into a created environment rather than the base environment. Here are some suggested steps, assuming that conda itself has been installed:
conda create --name myenv
conda activate myenv
conda install metview -c conda-forge
conda install metview-python -c conda-forge
Once this is done, any new shell should call the ‘conda activate’ command in order to use this Metview.
Virtualenv
Virtualenvs provide separate environments in which you can install Python packages. Binaries must be installed separately using one of the methods described above. For example, it could be a good idea to use Homebrew to install the binaries and use a virtualenv to install the Python bindings. Here’s a quickstart:
python3 -m venv $HOME/venvs/myenv
source $HOME/venvs/myenv/bin/activate
pip install metview
Once this is done, any new shell should call the above ‘source …./activate’ command in order to use these Metview Python bindings.
Possible Startup Issues
When starting Metview directly from the command line, the -slog option will provide output that may be useful:
metview -slog
The Python bindings can be tested for installation correctness by running the following command:
python3 -m metview selfcheck
If your environment has Metview installed or built but it is not in the system PATH, you can tell the Python bindings where to find it by setting this environment variable to the path to the ‘metview’ startup command:
export METVIEW_PYTHON_START_CMD=/path/to/build/metview/bin/metview
To activate extra debugging information, set this before starting Python:
export METVIEW_PYTHON_DEBUG=1
For more output from MARS requests, set this before starting Python:
export METVIEW_MARS_LOG=1
When you import metview, the Metview startup script is run in order to set up the working environment. Usually this is pretty much instant, but on very heavily loaded machines, it may take a few seconds. There is a default timeout of 8 seconds, but this can be increased if needed, by setting the following environment variable, to, for example, 15 seconds:
export METVIEW_PYTHON_START_TIMEOUT=15