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Python wrapper around the NAIF CSPICE library. Released under the BSD license, see LICENSE for details.

First, download the cspice toolkit and extract it to the directory "cspice" inthis directory right alongside the setup.py file. Once the cspice source isthere, run setup.py like so:

python setup.py build_ext

Then install:

python setup.py install

CSPICE is published in both 64 and 32 bit versions. Make sure that you compilePySPICE with a Python bit architecture that fits to the CSPICE you havedownloaded, otherwise you will get warnings at compile time (not so bad) anderrors of missing links in the library at run time (basically, you can'timportspice.

Though it shouldn't be necessary, here are the old step-by-step instructions.

In order to build this module, first generate the extension code using themkwrapper.py script. This is done running mkwrapper.py with the path to theCSPICE toolkit directory as an argument and redirecting the output to"spicemodule.c":

python mkwrapper.py /path/to/cspice > spicemodule.c

Once the C file is generated, the module can be compiled:

python setup.py build_ext -I/path/to/cspice/include -L/path/to/cspice/lib

Then the module can be installed using:

python setup.py install --prefix=/installation/path

If the installation path used is not standard, add the path to yourPYTHONPATH environment variable. In bash:

export PYTHONPATH=/installation/path/lib/python<version>/site-packages:${PYTHONPATH}

or*csh:

setenv PYTHONPATH /installation/path/lib/python<version>/site-packages:${PYTHONPATH}

berto:~$ pythonPython 2.4.2 (#2, Sep 30 2005, 21:19:01)[GCC 4.0.2 20050808 (prerelease) (Ubuntu 4.0.1-4ubuntu8)] on linux2Type "help", "copyright", "credits" or "license" for more information.>>> from spice import *>>> furnsh("/home/berto/tmp/insitu/kernels/load.mk")>>> utc2et("2004-06-11T19:32:00")140254384.18462521

The python wrapper drops the _c suffix in all function names, so thefunction utc2et_c becomes utc2et.

Also, the CSPICE toolkit passes both inputs and outputs into a SPICEfunction:

SpiceDouble et;SpiceChar * utc = "2004-06-11T19:32:00";utc2et_c(utc, &et);printf("et: %f\n", et);

But, in Python, the outputs are returned:

utc = "2004-06-11T19:32:00"et = utc2et(utc)print "et: %f" % et

If a function returns multiple values they are returned in a tuple:

target_pos, light_time = spkpos(target, sc_et, frame, aberration, sc_name)print "light time: %f" % light_timeprint "xyz: [%e, %e, %e]" % target_pos

In the case above, the target position and light time are returned in a tuple.Additionally, target_pos itself is a tuple; its individual elements can beaccessed like this:

print "x position: %d" % target_pos[0]

Tuples act just like arrays.

Enjoy!