GWDB Data Info

TODO fix table display

Data tarball for each simulation contain

  • An ASCII file metadata.txt with information about the configurations
  • A HDF5 file data.h5 with waveforms and GW energetics

The following table explains the meaning of the fields in the metadata.txt

Parameter Class Description

The content of an h5 file can be easily displayed using h5ls, e.g.

$ h5ls -r data.h5  

One possible outcome of the command is:

/                        Group
/energy                  Group
/energy/EJ_r00650.txt    Dataset {4099, 6}
/energy/EJ_r00700.txt    Dataset {4099, 6}
/energy/EJ_r00750.txt    Dataset {4099, 6}
/energy/EJ_r00800.txt    Dataset {4099, 6}
/energy/EJ_r00850.txt    Dataset {4099, 6}
/energy/EJ_r00900.txt    Dataset {4099, 6}
/rh_22                   Group
/rh_22/Rh_l2_m2_r00650.txt Dataset {4099, 9}
/rh_22/Rh_l2_m2_r00700.txt Dataset {4099, 9}
/rh_22/Rh_l2_m2_r00750.txt Dataset {4099, 9}
/rh_22/Rh_l2_m2_r00800.txt Dataset {4099, 9}
/rh_22/Rh_l2_m2_r00850.txt Dataset {4099, 9}
/rh_22/Rh_l2_m2_r00900.txt Dataset {4099, 9}
/rpsi4_22                Group
/rpsi4_22/Rpsi4_l2_m2_r00650.txt Dataset {4099, 7}
/rpsi4_22/Rpsi4_l2_m2_r00700.txt Dataset {4099, 7}
/rpsi4_22/Rpsi4_l2_m2_r00750.txt Dataset {4099, 7}
/rpsi4_22/Rpsi4_l2_m2_r00800.txt Dataset {4099, 7}
/rpsi4_22/Rpsi4_l2_m2_r00850.txt Dataset {4099, 7}
/rpsi4_22/Rpsi4_l2_m2_r00900.txt Dataset {4099, 7}

The dataset names should be self-explanatory, for example

  • EJ_r00650.txt contains energetics calculated with data extracted at coordinate radius 650Msun (See e.g. Damour et al (2011) for definitions of these quantities)
  • Rh_l2_m2_r00750.txt contains the 22-multipole of the metric waveform extracted at coordinate radius 750Msun
  • Rpsi4_l2_m2_r00850.txt contains the 22-multipole of the Psi4 waveform extracted at coordinate radius 850Msun

Each dataset can be dumped to an ASCII file, that also contains an header explaining the meaning of the columns. All the data are in Geometric units and often rescaled by the binary mass.

We recommend to read these data using python and the related HDF5 data packages directly, another simple way of extracting the information from the data in the following.
However, one can also use h5dump to dump the information into a ASCII file.

As an example, let us consider we want to check the 22 - multipole of the metric gravitational waveform at a radius of 800[Msun], i.e., /rh_22/Rh_l2_m2_r00800.txt . To output this dataset to an output file (say out.dat), use

$ h5dump -d /rh_22/Rh_l2_m2_r00800.txt -y -w 0 -o out.dat data.h5  

where

-y supresses the print of the array indices
-w sets the numer of columns for the output
-o sets the output file

This command also prints to the screen the important information about the data contained in the h5 file, e.g., the dataset_columns, the extratction radius, and the total Mass M. For more information about the formatting/output options, please refer to the h5dump manual. The file out.dat can now be read by any standard text editor and plotted e.g. with gnuplot or python.