Brute force coherence (Gabriele Vajente, 2017-01-23 vajente@caltech.edu)

Command line arguments (with default values)

--ifo interferometer prefix [H1, L1, V1] (no default, must specify)

--channel=OAF-CAL_DARM_DQ name of the main channel

--excluded=bruco_excluded_channels.txt file containing the list of channels excluded from the coherence computation

--gpsb=1087975458 starting time

--length=180 amount of data to use (in seconds)

--outfs=8192 sampling frequency of the output results (coherence will be computed up to outfs/2 if possible)

--minfs=512 skip all channels with samplig frequency smaller than this

--naver=100 number of averages to compute the coherence

--dir=bruco output directory

--top=100 for each frequency, save to cohtab.txt and idxtab.txt this maximum number of coherence channels

--webtop=20 show this number of coherence channels per frequency, in the web page summary

--plot=png plot format (png, pdf, none)

--nproc number of processes to use (if not specified, use all CPUs)

--calib name of a text file containing the calibration transfer function to be applied to the target channel spectrum, in a two column format (frequency, absolute value)

--xlim limits for the frequency axis in plots, in the format fmin:fmax

--ylim limits for the y axis in PSD plots, in the format ymin:ymax

--tmp=~/tmp temporary file directory where cache files will be saved if needed

Example: ./bruco.py --ifo=H1 --channel=CAL-DELTAL_EXTERNAL_DQ --calib=share/lho_cal_deltal_calibration.txt --gpsb=1111224016 --length=600 --outfs=4096 --naver=100 --dir=./bruco_1111224016 --top=100 --webtop=20 --xlim=1:1000 --ylim=1e-20:1e-14 --excluded=share/bruco_excluded_channels.txt"""

CHANGELOG:

2015-01-29 - added linear detrending in PSD and coherence to improve low frequency bins 2015-02-16 - split coherence computation into PSDs and CSDs to remove redundant computation of main channel PSD (still room to improve here) - removed upsampling of channels with lower sampling rate (now coherences are always computed with the minimum possible number of samples) 2015-02-18 - further splitting of coherence into primitive FFTs 2015-02-19 - allow selection of plot output format (PDF or PNG) 2015-02-24 - corrected typo in options lenght -> length - implemented parallel processing 2015-06-11 - using gw_data_find to locate the GWF files 2015-06-16 - added calibration transfer function option - added expanduser to all paths to allow use of ~ 2015-08-19 - now bruco removes the temporary files that contains the list of channels - timing information file is saved into the output directory 2015-01-01 - x3 faster plotting based on Michele Valentini's code 2016-09-19 - fixed bug in output table 2016-10-18 - added command line options for excluded channels file and temporary folder, updated default values
2016-10-26 - added portability to Virgo environment - removed old timing code - when invoked without arguments, print help 2016-10-28 - reverted to non packaged structure for simplicity 2016-11-11 - using direct frame file access to read data, instead of LAL cache (a couple of minutes faster) 2017-01-04 - using resample function if sampling frequency ratio is not integer 2017-01-05 - explicitly removing main channel from aux channel list 2017-01-23 - if the decimation ratio is greater than 10, decimate in mutiple steps to avoid numerical instabilities 2017-03-08 - Virgo sampling rate is not always a power of 2, and this caused a crash for some auxiliary channels with sampling rate lower than the desired output. Implemented an upsamping of the aux channel to solve the issue 2017-04-04 - mask frequencies above Nyquist