Different Time Series Plots and SNR when using pycbc and gwpy

Open Data Workshop
1

I have been attempting the data challenge and while working on the second one I noticed that using gwpy to read the “.gwf” file gives a duration of data different from that given when reading using pycbc.

Since I needed to find the q_transform as well I used the gwpy method first to load the data and then used the .to_pycbc() method to calculate the SNR time series. The answer I got here for the SNR peak differed from what I got when reading directly using pycbc and proceeding as usual.

I am not sure how to proceed.

Edit: I am able to get a much better q transform plot when using the pycbc approach. I still do not understand why the duration of the data is different.
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2

@aravbj Thank you for spotting this!

Some of the data files (file 1 and 2, I think) include some negative time values. Apparently, gwpy expects all time values to be positive, and seems to only read in the positive time values. I’ll try to fix this for next year.

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