Installing SnapPy

Here are detailed instructions on how to get SnapPy working on a variety of platforms. The current version is 2.5.4 which was released on August 5, 2017. If you encounter problems installing SnapPy, please let us know.

macOS/OS X

Simply download SnapPy.dmg and copy SnapPy.app to the Applications folder. Double-click to start it, just like any other application. Works with OS X versions 10.6 and newer. Users of earlier versions of OS X should install SnapPy-1.4.dmg instead.

Windows

Simply download and run InstallSnapPy.exe.

Linux

Here are short recipes which work on most Linux systems, specifically those that run a 64-bit kernel and use Python 2.7. These instructions assume you have system administrator (superuser) privileges; if not, you can install SnapPy into a virtual environment assuming the needed packages are installed. For other Linux systems, try the one closest to yours below, and if that fails, follow the instructions for generic Unix in the next section.

  • Fedora/RHEL/CentOS/SciLinux:

    sudo yum install tkinter python-setuptools python-ipython-console
    sudo python -m easy_install -U snappy
    

    Note: For this to work, you may need to set the SELinux Enforcement mode to Permissive or lower.

  • Ubuntu/Debian/Mint:

    sudo apt-get install python-tk python-setuptools ipython
    sudo python -m easy_install -U snappy
    
  • PCLinuxOS: Untested, but try the instructions for Ubuntu.

Once you have installed SnapPy, do:

python -m snappy.app

You may get a message about creating a “.ipython” directory; this is normal, just hit return to continue. There should also now be a command “SnapPy” which does the same thing.

Remark: If you prefer, you can install SnapPy on Linux using the most current pip rather than easy_install, just follow the instructions for Python Modules for Macintosh or Windows below adding sudo as necessary.

Generic Unix

If you use a Unix other than OS X or Linux, or if the prebuilt packages don’t work for you, you’ll need to build SnapPy from source. Here are some detailed instructions.

Things you’ll need:

  • Python with Tkinter: You’ll need to have Python (version 2.6-2.7) and Tk (at least version 8.4) with Tkinter to connect them, including the header files. For instance, on Debian or Ubuntu, install the packages “python-tk” and “python-dev”. On Fedora, you’ll want “tkinter” and “python-devel”. In addition, you’ll need setuptools, which is typically packaged as “python-setuptools”.

  • Test that Python is in order by installing PLink from source:

    python -m easy_install plink
    plink   # Should start the link editor!
    
  • Support for OpenGL (3D graphics): This is built in on OS X and the most installations of Fedora and Ubuntu. But you’ll need the MESA header files “gl.h” and “glu.h” to compile SnapPy. On Debian and Ubuntu, install “libglu1-mesa-dev”; On Fedora install “mesa-libGLU-devel”.

  • Cython, which you can install via:

    sudo python -m easy_install cython
    
  • The gcc C++ compiler, g++, which is not installed by default on some systems, e.g. Ubuntu 11.10.

  • CyPari: a stand-alone version of Sage’s Python interface to the PARI number theory library.

Now download the source code listed below, for instance

curl -L -O snappy-2.5.4.tar.gz
tar xfz snappy-2.5.4.tar.gz; cd SnapPy

There is one more dependency that may need to be dealt with:

  • Togl: a 3d widget for Tk. For OS X and Linux, there are pre-built binaries of this in the snappy subdirectory, e.g. snappy/linux2-tk8.4. For Linux these are built for both 32-bit and 64-bit kernels, and should work on most systems. If they don’t, you’ll need to edit or follow “build_togl.sh” to build Togl directly into “snappy/linux2-tk*” (32-bit kernel) or “snappy/linux2-x86_64-tk*” (64-bit kernel), where “*” is the version of Tk you are using.

Finally, compile and install the SnapPy module (which will install certain other dependencies) and test:

sudo python setup.py install
python -m snappy.app

You may get a message about creating a “.ipython” directory; this is normal, just hit return to continue. There should also now be a command “SnapPy” which does the same thing as “python -m snappy.app”.

Python Modules for Macintosh or Windows

If you write Python programs on a Macintosh or Windows system, you may wish to install SnapPy as a Python module into your own copy of Python 2.7. (For best results on macOS, use a Python downloaded from Python.org and not the one provided by Apple.) After installing Python, you may install a SnapPy module from your Terminal application or Command Prompt with the commands:

python -m pip install --upgrade pip setuptools
python -m pip install --upgrade --upgrade-strategy only-if-needed snappy

If your Python lacks the pip module, get it here.

Virtual Environment

All of the above instructions assume that you want to install SnapPy globally, in the main Python site-packages directory. You can also create a Python virtual environment and install SnapPy into it. For example, to install SnapPy into “mypy/bin” do:

# Create a virtual environment in new directory "mypy"
python -m virtualenv mypy
# Install and run SnapPy!
mypy/bin/easy_install snappy
mypy/bin/SnapPy

SageMath

SnapPy has some special features when used within SageMath, the universal mathematics software based on Python. You can install it as a Sage optional package via the following if using Sage 6.4 or newer:

sage -pip install snappy

If you are on macOS and it complains about not having SSL, TLS, or something related to a certificate missing, you likely have the problem described here so try this approach If you encounter other problems, on any platform, try:

sage -pip install --no-binary :all: snappy

For Sage 6.3 or older do:

sage -python -m easy_install snappy

Alternatively, SageMath on CoCalc (formerly the SageMathCloud) also has SnapPy preinstalled!

If you previously installed SnapPy into SageMath and want to upgrade SnapPy to the latest version, do:

sage -pip install --upgrade --no-deps snappy_manifolds plink spherogram FXrays decorator snappy

or:

sage -python -m easy_install -U snappy

as appropriate.

If it has trouble when compiling CyOpenGL, you are probably missing the “gl.h” headers. The graphical features may or may not work, depending on how Tkinter was configured within Sage, and may seem to “hang” when you try to start them. To deal with the latter issue on Sage 5.11 or later, type “%gui tk” at the Sage prompt; please note that doing so may break Sage’s “attach” feature.

Source code

The complete source code for all platforms: snappy-2.5.4.tar.gz

You can also browse our source code repository or clone it using Mercurial via:

hg clone https://bitbucket.org/t3m/snappy

Python 3

We now fully support using SnapPy with Python 3! Currently, binaries are provided for Python 3.4, 3.5, and 3.6 on macOS, Linux, and Windows. We offer stand-alone application for macOS (SnapPy-Python3.dmg) and Windows (InstallSnapPy-Python3.exe). You can also install the Python modules into your Python via the following, with Linux users needing to add sudo at the start of each line:

python3 -m pip install --upgrade pip setuptools
python3 -m pip install --upgrade --upgrade-strategy only-if-needed snappy
python3 -m snappy.app