sdynpy.compute_residues

• Defined as: sdynpy.modal.sdynpy_modeshape.compute_residues

• Also available as:

  • sdynpy.modal.compute_residues

• Module: sdynpy.modal.sdynpy_modeshape

• Source: GitHub

Signature¶

def sdynpy.compute_residues(experimental_frf: sdynpy.core.sdynpy_data.TransferFunctionArray, natural_frequencies: numpy.ndarray, damping_ratios: numpy.ndarray, real_modes: bool = False, residuals: bool = True, min_frequency: float = None, max_frequency: float = None, weighting: numpy.ndarray = 'uniform', displacement_derivative: int = 0, frequency_lines_at_resonance: int = None, frequency_lines_for_residuals: int = None)

Fit residues to FRF data given frequency and damping values

Parameters¶

• experimental_frf : TransferFunctionArray Experimental FRF data to which modes will be fit

• natural_frequencies : np.ndarray Natural Frequencies (in Hz) at which modes will be fit

• damping_ratios : np.ndarray Damping Ratios at which modes will be fit

• real_modes : bool, optional If true, fit residues will be real-valued. False allows complex modes. The default is False.

• residuals : bool, optional Use residuals in the FRF fit. The default is True.

• min_frequency : float, optional Minimum frequency to use in the shape fit. The default is the lowest frequency in the experimental FRF.

• max_frequency : float, optional Maximum frequency to use in the shape fit. The default is the highest frequency in the experimental FRF.

• weighting : np.ndarray or string, optional A weighting array to use to fit shapes better at specific frequencies. The default is weighted by the log magnitude of the FRF matrix. Can be defined as ‘magnitude’,‘uniform’, or an ndarray with shape identical to the ordinate of the experimental frfs

• displacement_derivative : int, optional Defines the type of data in the FRF based on the number of derivatives from displacement (0 - displacement, 1 - velocity, 2 - acceleration). The default is 0 (displacement).

• frequency_lines_at_resonance : int, optional Defines the number of frequency lines to look at around the specified natural frequencies for computing residues. If not specified, all frequency lines are used for computing shapes.

• frequency_lines_for_residuals : int, optional Defines the number of frequency lines at the low and high frequency to use in computing shapes. Only used if frequency_lines_at_resonance is specified. If not specified, the lower 10% and upper 10% of frequency lines will be kept.

Returns¶

• shape_residues : np.ndarray A (..., n_modes) shaped np.ndarray where ... is the shape of the input experimental_frf array. There will be one residue for each experimental frf (reference and response) for each mode.

• synthesized_frf : TransferFunctionArray Transfer function array containing the analytical fits using the residues.

• residual_frf : TransferFunctionArray Transfer function array containing the residual data from the analytical fits.