Installation

The following sections should help you install the library on your machine. Instead of installing the library system-wide, the instructions show how to install it within in a virtual environment. This avoids interfering with your operating system or other libraries, when you should upgrade some libraries.

Some of the instructions are based on the CellProfiler instructions, the guys behind the javabridge library.

However, if you should encounter problems or if you would like to submit improvements on the instructions below, please use the following mailing list:

https://groups.google.com/forum/#!forum/python-weka-wrapper

Prerequisites for all platforms

You need a Java Development Kit (JDK) 8 or later (e.g., OpenJDK) installed and the JAVA_HOME environment variable pointing to the installation directory in order to use python-weka-wrapper3 library.

Note: In the past, it was not recommended to use OpenJDK, as Weka was developed with and tested against Oracle’s version. However, Oracle’s JDK 8 is no longer available for public download and OpenJDK matured enough that it is now the recommended Java version to use. Personally, I recommend the long-term support version 11 of OpenJDK.

Ubuntu

First, you need to be able to compile C/C++ code and Python modules:

sudo apt-get install build-essential python3-dev

Now, you can install the various packages that we require for installing python-weka-wrapper3:

sudo apt-get install python3-pip python3-numpy python3-venv

The following packages are optional, but necessary if you also want some graphical output:

sudo apt-get install python3-pil python3-matplotlib python3-pygraphviz

Install OpenJDK as well, in order to get all the header files that javabridge compiles against (but don’t use it for starting up JVMs):

sudo apt-get install default-jdk

Create a virtual environment using the venv module that :

python3 -m venv pww3

Finally, you can use pip from the virtual environment to install the Python packages that are not available in the Ubuntu repositories:

./pww3/bin/pip install python-javabridge
./pww3/bin/pip install python-weka-wrapper3

Debian

First, become the superuser:

su

You need to be able to compile C/C++ code and Python modules:

apt-get install build-essential python3-dev

Now, you can install the various packages that we require for installing `python-weka-wrapper3:

apt-get install python3-pip python3-numpy python3-venv

The following packages are optional, but necessary if you also want some graphical output:

apt-get install python3-pil python3-matplotlib python3-pygraphviz

Older Debian versions used python3-imaging instead of python3-pil.

Download a JDK and un-tar it in /opt (e.g., /opt/jdk-11.0.7+10/).

Exit superuser mode and become a regular user again.

Export the Java home directory as follows, which is required for the javabridge installation/compilation (you might want to add this command to your .profile):

export JAVA_HOME=/opt/jdk-11.0.7+10/

Create a virtual environment using the venv module that :

python3 -m venv pww3

Finally, you can use pip from the virtual environment to install the Python packages that are not available in the Debian repositories:

./pww3/bin/pip install python-javabridge
./pww3/bin/pip install python-weka-wrapper3

Please note, when using python-weka-wrapper3 as a normal user, don’t forget to export the JAVA_HOME environment variable as described above (e.g., add it to your .profile).

Fedora/CentOS/Redhat

Here are some rough instructions (as superuser):

  • install openjdk (+ -devel) package

  • install python (+ -devel) package

  • download pip from https://bootstrap.pypa.io/get-pip.py

  • install pip using python get-pip.py

  • install dev tools using yum groupinstall "Development tools"

  • install numpy package

  • install python-imaging package (shouldn’t be necessary)

As regular user:

  • create a virtual environment (see Ubuntu/Debian sections above)

  • install javabridge using ./venv/bin/pip javabridge

  • install python-weka-wrapper3 using ./venv/bin/pip python-weka-wrapper3

Other Linux distributions

See these general instructions for installing Python on Linux. You need to be able to compile C/C++ code and Python modules (i.e., Python header files are required). By installing OpenJDK, you should be able to compile javabridge against its header files (for JNI access).

Then you need to install the following Python packages, preferably through your package manager (e.g., yum). Please note that on a headless machine, you can omit the packages marked as optional, as they are only required for graphical output and plots:

  • pip3

  • numpy

  • PIL (optional)

  • matplotlib (optional)

  • pygraphviz (optional)

Create a virtual environment using the venv module that :

python3 -m venv pww3

Once these libraries are installed, you can use pip from the virtual environment to install the Python packages that are not available in the distro repositories:

./pww3/bin/pip install python-javabridge
./pww3/bin/pip install python-weka-wrapper3

COLAB

In a Python 3 COLAB environment, you need to install at least these modules to get python-weka-wrapper3 working:

!pip install numpy
!pip install python-javabridge
!pip install python-weka-wrapper3

Notes:

  • Once the JVM has been stopped, you might have to restart the COLAB runtime

  • After installing packages, you need to restart the COLAB runtime, otherwise the packages won’t be available to the JV

Mac OSX

Please follow these general instructions for installing Python.

In order to compile C/C++ code, you need to install Xcode through Apple’s App Store. Once installed you can install the XCode command-line tools by issuing the command xcode-select --install in a terminal.

Also, install graphviz using homebrew (brew install pkg-config and brew install graphviz) for visualizing trees and graphs.

You need to install the following Python packages:

  • numpy

  • pillow

  • matplotlib

  • pygraphviz

  • lxml

  • python-javabridge

Once these libraries are installed, you can use pip to install the remaining Python packages:

pip3 install python-weka-wrapper3

Windows using Anaconda

Please note: You need to make sure that the bitness of your environment is consistent. I.e., if you install a 32-bit version of Anaconda, you need to install a 32-bit JDK (or all of them are 64-bit).

  • set the JDK_HOME environment variable to point at the same directory as JAVA_HOME

  • download and install the Visual C++ Build Tools, select the Desktop development with C++ option in the installer

  • the following configures an environment with Python 3.10 (3.11+ does not work at this stage)

    conda create --name pww3 python=3.10
conda activate pww3
conda install -c conda-forge numpy
conda install -c conda-forge pillow
pip install python-javabridge
pip install python-weka-wrapper3

If you want plotting support, then install also graphviz and matplotlib:

  • download graphviz and add the path to its installed binaries to your PATH environment variable.

  • install pygraphviz and matplotlib:

    conda install -c conda-forge pygraphviz
conda install -c conda-forge matplotlib

Windows

Please note: You need to make sure that the bitness of your environment is consistent. I.e., if you install a 32-bit version of Python, you need to install a 32-bit JDK and 32-bit numpy (or all of them are 64-bit).

Perform the following steps:

  • set the JDK_HOME environment variable to point at the same directory as JAVA_HOME

  • download and install the Visual C++ Build Tools, select the Desktop development with C++ option in the installer

  • install Python (<=3.10), make sure you check Add python.exe to path during the installation

  • add the Python scripts directory to your PATH environment variable, e.g., C:\\Python310\\Scripts

  • install pip with these steps:

  • download from here

  • install using python get-pip.py

  • install numpy:

pip install numpy

  • install python-javabridge:

pip install python-javabridge

  • install python-weka-wrapper3:

pip install python-weka-wrapper3

If you want to use the plotting functionality, you need to install graphviz and matplotlib as well:

  • download graphviz and add the path to its installed binaries to your PATH environment variable.

pip install matplotlib pygraphviz pillow lxml

From source

You have two options for installing the library from source, either through a release archive or using the bleeding edge source code that is available through the Github repository.

Release archive

Go to the releases page on Github and download the Source code archive (zip or tar.gz) of the release that you want to install. After the download finishes, decompress the archive. Open a terminal/command prompt and execute the following command from within the directory with the setup.py file:

./venv/bin/python setup.py install

Check out the section on virtualenv as well, if you would rather install it in a disposable location.

Github

You can install python-weka-wrapper3 directly from its Github repository with pip as follows (e.g., to get the latest fixes/features):

./venv/bin/pip install git+https://github.com/fracpete/python-weka-wrapper3.git

Alternatively, you can clone the repository separately and install it from there.

First, clone the Github repository as follows:

git clone https://github.com/fracpete/python-weka-wrapper3.git

Second, change into the newly created directory and install the library using the following command (adjusting the path to your virtual environment):

./venv/bin/python setup.py install