Tutorials Questions - Day 1

Open Data Workshop
41 
from gwosc.datasets import event_gps
from gwpy.timeseries import TimeSeries

gps=event_gps('GW170814')
detectors=['L1','H1','V1']
for place in detectors:
  ldata=TimeSeries.fetch_open_data(place, int(gps)-512, int(gps)+512,cache=True)
  lq=ldata.q_transform(frange=(30,500),qrange=(4,12),outseg=(gps-0.1,gps+0.1))
  lq=lq**0.5
  plot=lq.plot()
  ax=plot.gca()
  ax.set_epoch(gps)
  ax.set_yscale('log')

This was my code for Tutorial 1.4. There are certain white patches on my plot that look like this:

image
image949Ɨ501 87.5 KB

What is the explanation for this?

42

Hi @AmbicaG , really strange plot, the only thing I suspect is that some spectrogram values could be out of range or (more likely) invalid numbers, can you try to plot the power spectrogram only, i.e. without doing lq=lq^0.5? Or also, can you check something like numpy.isnan(lq).any() and also numpy.isnan(lq^0.5).any()?

43

@FabioNovaes Thank you! Please let us know what you find.

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Hi, Jonah,

I couldnā€™t figure it out whatā€™s the problem with TimeSeries.fetch_open_data. Iā€™m not having the ā€œread timeout errorā€ as before. However, the 512 sec window data takes around 28 minutes to download, too long for files with at most 0.4 GB in my internet connection, but okay. Iā€™ve just considered it a fact of life and moved on.

Now, in tutorial 1.4, when I use the igwn-py39 kernel, I only get the following waveforms:

Time domain waveforms:  ['TaylorF2NL', 'PreTaylorF2', 'SpinTaylorF2_SWAPPER']
Frequency domain waveforms:  ['SpinTaylorF2_SWAPPER', 'TaylorF2NL', 'PreTaylorF2', 'multiband', 'TaylorF2NL_INTERP', 'PreTaylorF2_INTERP', 'SpinTaylorF2_SWAPPER_INTERP']

However, using the igwn-py39-lw kernel, it loads all waveforms. It might be some kind of problem of my (old) Mac OS system with the packages listed in the full environment. I believe this is related to the lalsuite package. I noticed that the lightweight enviroment file has lalsuite=7.11, while the full env file has lalsuite=7.15=pyhd8ed1ab_0. This can be found out using conda compare enviroment.yml with the full environment active. The pip package is also a mismatch, but I donā€™t think it should be a problem. For the moment, the lightweight enviroment is working for me. Iā€™m just reporting for you guys to check for the consistency of the enviroment files.

45

Thank you! Iā€™m not sure why thatā€™s happening, but I appreciate you letting us know.