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Update home authored by Wei Changfeng's avatar Wei Changfeng
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...@@ -227,7 +227,7 @@ However, SNR would be good if it is greater than 10. This can be fixed by adjust ...@@ -227,7 +227,7 @@ However, SNR would be good if it is greater than 10. This can be fixed by adjust
SNR_L1 = 21.86, SNR_H1 = 18.43, SNR_V1 = 10.87 SNR_L1 = 21.86, SNR_H1 = 18.43, SNR_V1 = 10.87
Now they well meet the requirement. Now they well meet the requirement.
## (10)t_zero ## (10)t_zero
In a waveform, t_zero is defined as a time coordinate where the absolute maximum amplitude is. It's also an injection parameter called geocent_time in geocentric reference system. In a waveform, t_zero is defined as a time coordinate where the absolute maximum amplitude is. It's also an injection parameter called geocent_time in geocentric reference system. However, till now I don't think the reference frame transformation matters to VItamin analysis, since what VItamin expects is just 'y_noisy_data', instead of 'time' series.
## (11)Whitening comparision ## (11)Whitening comparision
Problem: It looks like the amplitude of bilby whitened signal has a greater order of magnitude(10^1, which supposed to be 10^0). So I make a comparision between Hunter's whitening method and mine. Problem: It looks like the amplitude of bilby whitened signal has a greater order of magnitude(10^1, which supposed to be 10^0). So I make a comparision between Hunter's whitening method and mine.
First, Hunter gets frequency domain noise-free signals at detector directly, instead of getting time domain signals and make Fourier transform. First, Hunter gets frequency domain noise-free signals at detector directly, instead of getting time domain signals and make Fourier transform.
...@@ -244,11 +244,16 @@ signal_time_domain= ifos[k].time_domain_strain ...@@ -244,11 +244,16 @@ signal_time_domain= ifos[k].time_domain_strain
# k is the ordinal number of detectors # k is the ordinal number of detectors
signal_freq_domain = np.fft.rfft(signal_time_domain) signal_freq_domain = np.fft.rfft(signal_time_domain)
``` ```
If both of 2 methods above are correct, 2 frequency domain signals they get should be the same, at least very similar. If both of 2 methods above are correct, 2 frequency domain signals we get should be the same, at least very similar.
However, They are very different. Actually, They are similar in shape but the order of magnitude are very different. I don't know why.
to be continued... ![signal_freq_Weichangfeng_method](uploads/8e27887501d8aba9a1631c05342d6a3f/signal_freq_Weichangfeng_method.png)
![signal_freq_Hunter_method](uploads/c5b668283727bdc9f544f81ea23465ee/signal_freq_Hunter_method.png)
## (12)VItamin: Bilby BBH waveform new test ## (12)VItamin: Bilby BBH waveform new test
In this test we get frequency domain noise-free signal at detector directly, instead of getting time domain signal and make Fourier transform. Though there are some problems above, we can still test VItamin by following the way that Hunter trains it strictly. In this test we get frequency domain noise-free signals at detector directly.
![data_20201018](uploads/bbccc16a12c1987a302cb0a697da0ac3/data_20201018.png)
# 2.Data # 2.Data
## (1)Korean merger wavform ## (1)Korean merger wavform
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