pylops.waveeqprocessing.UpDownComposition3D¶

pylops.waveeqprocessing.UpDownComposition3D(nt, nr, dt, dr, rho, vel, nffts=(None, None, None), critical=100.0, ntaper=10, scaling=1.0, backend='numpy', dtype='complex128')[source]¶

3D Up-down wavefield composition.

Apply multi-component seismic wavefield composition from its up- and down-going constituents. The input model required by the operator should be created by flattening the separated wavefields of size \(\lbrack n_{r_y} \times n_{r_x} \times n_t \rbrack\) concatenated along the first spatial axis.

Similarly, the data is also a flattened concatenation of pressure and vertical particle velocity wavefields.

Parameters:

nt : int: Number of samples along the time axis
nr : tuple: Number of samples along the receiver axes
dt : float: Sampling along the time axis
dr : tuple: Samplings along the receiver array
rho : float: Density \(\rho\) along the receiver array (must be constant)
vel : float: Velocity \(c\) along the receiver array (must be constant)
nffts : tuple, optional: Number of samples along the wavenumbers and frequency axes (for the wavenumbers axes the same order as nr and dr must be followed)
critical : float, optional: Percentage of angles to retain in obliquity factor. For example, if critical=100 only angles below the critical angle \(\sqrt{k_y^2 + k_x^2} < \frac{\omega}{c}\) will be retained
ntaper : float, optional: Number of samples of taper applied to obliquity factor around critical angle
scaling : float, optional: Scaling to apply to the operator (see Notes for more details)
backend : str, optional: Backend used for creation of obliquity factor operator (numpy or cupy)
dtype : str, optional: Type of elements in input array.

Returns:

UDop : pylops.LinearOperator: Up-down wavefield composition operator