Working with GWOSC Data Using C
C developers have at least two options for libraries that will read GWOSC data files - the Frame Library and HDF5. If you have no strong reason to prefer C, you may find the python-based instructions in the Introductory Tutorial a quicker way to get started.The Frame Library
GWOSC data files in the gravitational wave frame file format (.gwf) may be read using the Frame Library.- For Frame Library documentation, see the Frame Library Home Page
- For installation suggestions, see the Frame Library and LSC Software Installation page.
HDF5
GWOSC data files in the HDF5 file format (.hdf5) may be read using the HDF5 Library.- The script hdf5_losc.c demonstrates how to read a GWOSC data file using the HDF5 library.
- An example LIGO data file may be downloaded here.
- HDF5 library documentation and installation instructions are available on the HDF Group Web Site.
In the GWOSC computing enviornment, the example script may be compiled with this command:
gcc -o hdf5_losc hdf5_losc.c -lhdf5 -D H5_USE_16_APIOn a mac, macports may be used to install HDF5, in which case the example script may be compiled with a command similar to this:
gcc -o hdf5_losc hdf5_losc.c -lhdf5 -D H5_USE_16_API -I /opt/local/include -L/opt/local/libAll computing envoirnments are a little different, so compiling on your computer may not work in exactly the same way.
Running the example script should produce output similar to this:
$ ./hdf5_losc /quality/simple/DQmask: [ 196591 196591 196591 196591 196591 196591 196591 196591 196591 196591 ... ] The total live time for this 4096 s file is: 3481 seconds /strain/Strain: [ 8.302311e-17 9.192293e-17 1.007950e-16 1.095800e-16 1.182704e-16 1.269312e-16 1.354517e-16 1.439318e-16 1.522801e-16 1.605206e-16 ... ]