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Your recommended download:
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The latest development version is 3.3.0a57 Lentiform Loewenfeld, released on Unreleased (release notes).
The recommended download is based on Python 3.7. The installer and
.zip packages are identical, except for the installation.
Some Python packages are not compatible with Python 3. If you want to use those, please download the Python 2.7 package below. Note: As of January 1, 2020, Python 2.7 is no longer maintained.
Mac OS packages are not yet available. For now, you can install OpenSesame 3.3 on Mac OS through Anaconda (see below).
OpenSesame 3.3 is available through the Rapunzel PPA. To add this repository to your software sources and install OpenSesame, run the following commands in a terminal:
sudo add-apt-repository ppa:smathot/rapunzel sudo apt-get update sudo apt-get install python3-opensesame opensesame-extension-osf opensesame-extension-osweb opensesame-plugin-psychopy # To install also rapunzel, the OpenSesame-based code editor sudo apt-get install python3-rapunzel
Some commonly used packages are not available through the PPA. You can install them through
pip install psychopy expyriment
Arch Linux packages are available in the Arch Linux user repository.
Pip / PyPi (cross-playform)
To install OpenSesame from PyPi (Python package index), type:
pip install python-opensesame
First, create a new Python environment for OpenSesame (optional):
conda create -n opensesame-py3 python=3.7.3 # For Python 2: ptyhon=2.7.15 conda activate opensesame-py3
Next, add the relevant channels (
cogsci) and (
conda-forge) and install all relevant packages:
conda config --add channels cogsci --add channels conda-forge conda install python-opensesame opensesame-extension-osf opensesame-extension-osweb opensesame-plugin-psychopy psychopy rapunzel
PyGaze, a Python eye-tracking library, is only available on Python 2.
conda install python-pygaze
Older versions can be downloaded from GitHub releases:
The source code of OpenSesame is available on GitHub.
Which version of Python to use?
OpenSesame is currently built with Python 3.7.3 (standard package) and Python 2.7.15.
When (not) to update?
- Update while developing and testing your experiment; it is always best to use the latest version of OpenSesame.
- Do not update while running an experiment; that is, do not update while you are collecting data.
- Run an experiment with the same version of OpenSesame that you used for developing and testing.
Manually upgrading packages
- OpenSesame is a regular Python environment, and you can upgrade packages with
pipas described here:
Tips for system administrators
- When a new major version of OpenSesame is released (with a version ending in 0, e.g. 3.1.0), it is generally followed quickly by one or two maintenance releases (e.g. 3.1.1 and 3.1.2) that address major bugs. Therefore, if you are installing OpenSesame on systems that you do not update often, it is best to wait until the second or third maintenance release (e.g. 3.0.2, 3.1.3, etc.). That way you minimize the risk of rolling out a version of OpenSesame that contains major bugs.
- The Windows installer allows you to silently install OpenSesame using the