SpiceyPy is currently supported on Mac, Linux, FreeBSD, and Windows systems.
If you are new to python, it is a good idea to read a bit about it first https://docs.python-guide.org. For new installations of python, it is encouraged to install and or update: pip, setuptools, wheel, and numpy first before installing SpiceyPy
pip install -U pip setuptools wheel pip install -U numpy
Then to install SpiceyPy, simply run:
pip install spiceypy
If you use anaconda/miniconda/conda run:¶
conda config --add channels conda-forge conda install spiceypy
If no error was returned you have successfully installed SpiceyPy. To verify this you can list the installed packages via this pip command:
You should see spicepy in the output of this command. Or you can start a python interpreter and try importing SpiceyPy like so:
import spiceypy # print out the toolkit version installed print(spiceypy.tkvrsn('TOOLKIT'))
This should print out the toolkit version without any errors. You have now verified that SpiceyPy is installed.
If you need to install SpiceyPy without a network or if you have a prebuilt shared library at hand, you can override the default behaviour of SpiceyPy by using the CSPICE_SRC_DIR and CSPICE_SHARED_LIB environment variables respectively.
For example, if you have downloaded SpiceyPy and the CSPICE toolkit, and extracted CSPICE to /tmp/cspice you can run:
export CSPICE_SRC_DIR="/tmp/cspice" python setup.py install
Or if you have a shared library of CSPICE located at /tmp/cspice.so, you can run:
export CSPICE_SHARED_LIB="/tmp/cspice.so" python setup.py install
Both examples above assume you have cloned the SpiceyPy repository and are running those commands within the project directory.
A simple example program¶
This script calls the spiceypy function ‘tkvrsn’ and outputs the return value.
File tkvrsn.py from __future__ import print_function import spiceypy def print_ver(): """Prints the TOOLKIT version """ print(spiceypy.tkvrsn('TOOLKIT')) if __name__ == '__main__': print_ver()
From the command line, execute the function:
$ python tkvrsn.py CSPICE_N0066
From Python, execute the function:
$ python >>> import tkvrsn >>> tkvrsn.print_ver() CSPICE_N0066
The current version of SpiceyPy does not provide extensive documentation, but there are several ways to navigate your way through the Python version of the toolkit. One simple way is to use the standard Python mechanisms. All interfaces implemented in SpiceyPy can be listed using the standard built-in function dir(), which returns an alphabetized list of names comprising (among) other things, the API names. If you need to get additional information about an API parameters, the standard built-in function help() could be used:
>>> import spiceypy >>> help(spiceypy.tkvrsn)
Help on function tkvrsn in module spiceypy.spiceypy: tkvrsn(item) Given an item such as the Toolkit or an entry point name, return the latest version string. https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/tkvrsn_c. html :param item: Item for which a version string is desired. :type item: str :return: the latest version string. :rtype: str
As indicated in the help on the function, the complete documentation is available on the CSPICE toolkit version. Therefore it is recommended to have the CSPICE toolkit version installed locally in order to access its documentation offline.
SSL Alert Handshake Issue¶
As of 2020, users are not likely to experience this issue with python version 3.7 and above, and for newer 3.6.X releases. Users running older operating systems are encouraged to update to newer versions of python if they are attempting to install version 3.0.0 or above. See other sections of this document for more information.
In early 2017, JPL updated to a TLS1.2 certificate and enforced https connections causing installation issues for users, in particular for macOS users, with OpenSSL versions older than 1.0.1g. This is because older versions of OpenSSL still distributed in some environments which are incompatible with TLS1.2. As of late 2017 SpiceyPy has been updated with a strategy that can mitigate this issue on some systems, but it may not be totally reliable due to known deficiencies in setuptools and pip.
Another solution is to configure a new python installation that is linked against a newer version of OpenSSL, the easiest way to do this is to install python using homebrew, once this is done spiceypy can be installed to this new installation of python (IMHO this is the best option).
If your python 3.6 distribution was installed from the packages available at python.org an included command “Install Certificates.command” should be run before attempting to install SpiceyPy again. That command installs the certifi package that can also be install using pip.
Alternatively, installing an anaconda or miniconda python distribution and installing SpiceyPy using the conda command above is another possible work around.
Users continuing to have issues should report an issue to the github repository.
How to install from source (for bleeding edge updates)¶
If you have used the pip or conda install commands above you do not need to do any of the following commands. Installing from source is intended for advanced users. Users on machines running Windows should take note that attempting to install from source will require software such as visual studio and additional environment configuration. Given the complexity of this Windows users are highly encouraged to stick with the releases made available through PyPi/Conda-Forge.
If you wish to install from source, first simply clone the repository by running the following in your favorite shell:
git clone https://github.com/AndrewAnnex/SpiceyPy.git
If you do not have git, you can also directly download the source code from the GitHub repo for SpiceyPy at https://github.com/AndrewAnnex/SpiceyPy
To install the library, simply change into the root directory of the project and then run:
python setup.py install
The installation script will download the appropriate version of the SPICE toolkit for your system, and will build a shared library from the included static library files. Then the installation script will install SpiceyPy along with the generated shared library into your site-packages directory.