Auxiliary Functions
- gwtails.auxiliary.compute_tail_exponent(t, f, use_filter=True, window_length=800, polyorder=4)[source]
Compute tail exponent p from time series data.
Parameters:
- tarray-like
Time array
- farray-like
Strain/psi4 amplitude data
- use_filterbool, default True
Whether to apply Savgol filter to the computed exponent
- window_lengthint, default 800
Length of filter window (must be odd)
- polyorderint, default 4
Order of polynomial used in filtering
Returns:
- parray-like
Tail exponent (filtered if use_filter=True)
- gwtails.auxiliary.compute_frequency(t, h, method='spline', s=0.01, window_length=800, polyorder=4)[source]
Computes orbital frequency of a given gravitational wave time-series.
Parameters:
- tarray-like
Time array
- harray-like
Waveform mode array or psi4 array
- methodstr, default ‘spline’
Method for computing frequency: ‘spline’ or ‘savgol’
- sfloat, default 0.01
Smoothing parameter for spline interpolation
- window_lengthint, default 800
Window length for Savgol filter (used if method=’savgol’)
- polyorderint, default 4
Polynomial order for Savgol filter
Returns:
- freqarray-like
Orbital frequency
- gwtails.auxiliary.find_tail_start(t, h, freq_threshold=0.001, consecutive_zeros=5, method='spline', merger_time=10, **freq_kwargs)[source]
Find the start of the tail by detecting consecutive frequency zeros.
Parameters:
- tarray-like
Time array
- harray-like
Strain/psi4 data
- freq_thresholdfloat, default 1e-4
Threshold below which absolute frequency is considered zero
- consecutive_zerosint, default 5
Number of consecutive zero frequencies required
- methodstr, default ‘spline’
Method for frequency computation (‘spline’ or ‘savgol’)
- merger_timefloat, default 10
Time before which data is ignored (ensures tail is after merger)
- **freq_kwargsdict
Additional arguments for compute_frequency function
Returns:
- tail_start_timefloat
Time at which tail starts
- tail_start_indexint
Index at which tail starts (in original array)
- frequencyarray
Computed normalized frequency array
- zero_maskarray
Boolean mask showing where frequency is considered zero