sdynpy.signal_processing.sdynpy_srs.generate_single_windowed_random_realization

• Module: sdynpy.signal_processing.sdynpy_srs

• Source: GitHub

Signature¶

def sdynpy.signal_processing.sdynpy_srs.generate_single_windowed_random_realization(ref_srs: numpy.ndarray, window: numpy.ndarray, sample_rate: float, gravity: float = 386.0, damping: float = 0.03, srs_type: int = 9, match_points_per_octave: float = 4.0, output_points_per_octave: float = 12.0, amp_init: Optional[numpy.ndarray] = None, phase_init: Optional[numpy.ndarray] = None, iterations: int = 10, correction: float = 0.8, error_tolerance: float = 0.05, randomize_phase: bool = False, max_frequency: Optional[float] = None, rng: Optional[numpy.random._generator.Generator] = None) -> Dict[str, Any]

Generate a single windowed random realization matched to a target SRS.

Parameters¶

• ref_srs : ndarray Target SRS breakpoint array with shape (n_breakpoints, 2). The first column is frequency and the second is SRS amplitude.

• window : ndarray Time-domain window with shape (n_samples,).

• sample_rate : float Sampling rate in samples per second.

• gravity : float, default=386.0 Acceleration-of-gravity conversion factor used when integrating to velocity and displacement.

• damping : float, default=0.03 Fraction of critical damping used for SRS calculations.

• srs_type : int, default=9 SRS type passed to :func:sdynpy_srs.srs.

• match_points_per_octave : float, default=4.0 Frequency resolution used during the iterative SRS matching process.

• output_points_per_octave : float, default=12.0 Frequency resolution used for the returned SRS curve.

• amp_init : ndarray, optional Initial spectrum amplitude guess as a two-column array [frequency, amplitude].

• phase_init : ndarray, optional Initial one-sided phase vector in radians.

• iterations : int, default=10 Maximum number of matching iterations.

• correction : float, default=0.8 Fraction of the SRS error corrected at each iteration.

• error_tolerance : float, default=0.05 Relative SRS error tolerance for convergence.

• randomize_phase : bool, default=False If True, ignore phase_init and generate a random phase realization.

• max_frequency : float, optional Maximum frequency for nonzero Fourier amplitude. If not specified, the default is min(sample_rate/4, ref_srs[-1, 0]).

• rng : numpy.random.Generator, optional Random number generator used when random phase is required.

Returns¶

• dict

• Dictionary containing:

• - "time" : ndarray

• Time vector.

• - "xc" : ndarray

• Compensated windowed acceleration history.

• - "rr" : ndarray

• Stationary random acceleration history before windowing.

• - "srs_freq" : ndarray

• Frequency vector for the returned SRS.

• - "srs_values" : ndarray

• SRS values for the returned realization.

• - "srsc" : ndarray

• Matching-frequency SRS array with columns [frequency, amplitude].

• - "metrics" : WindowedRandomMetrics

• Scalar metrics for the realization.

• - "amp" : ndarray

• Final matched spectral amplitudes at the matching frequencies.

• - "phase" : ndarray

• Final phase vector used for waveform synthesis.

Raises¶

• ValueError

• If the FFT line spacing is too coarse to resolve the lowest matched SRS

• frequency, or if the internally defined frequency grid is invalid.

Notes¶

This function is the numerical core corresponding to one pass through the MATLAB wrcomp_tdh / gwinrand workflow.