wecopttool.core

Core functionality for solving the pseudo-spectral problem for WEC.

Contains:

• The WEC class

• Functions for basic functionality

Note

All contents of this module are imported into WecOpTool and can be called directly as wecopttool.<function> instead of wecopttool.core.<function>.

Classes

WEC	A wave energy converter (WEC) object for performing simulations using the pseudo-spectral solution method.

Functions

ncomponents	Number of Fourier components (2*nfreq) for each DOF.
frequency	Construct equally spaced frequency array.
time	Assemble the time vector with nsubsteps subdivisions.
time_mat	Assemble the time matrix that converts the state to a time-series.
derivative_mat	Assemble the derivative matrix that converts the state vector of a response to the state vector of its derivative.
derivative2_mat	Assemble the second derivative matrix that converts the state vector of a response to the state vector of its second derivative.
mimo_transfer_mat	Create a block matrix of the MIMO transfer function.
vec_to_dofmat	Convert a vector back to a matrix with one column per DOF.
dofmat_to_vec	Flatten a matrix that has one column per DOF.
real_to_complex	Convert from two real amplitudes to one complex amplitude per frequency.
complex_to_real	Convert from one complex amplitude to two real amplitudes per frequency.
fd_to_td	Convert a complex array of Fourier coefficients to a real array of time-domain responses.
td_to_fd	Convert a real array of time-domain responses to a complex array of Fourier coefficients.
read_netcdf	Read a NetCDF file with possibly complex entries as a xarray.Dataset.
write_netcdf	Save an xarray.Dataset with possibly complex entries as a NetCDF file.
check_radiation_damping	Ensure that the linear hydrodynamics (friction + radiation damping) have positive damping.
check_impedance	Ensure that the real part of the impedance (resistive) is positive.
force_from_rao_transfer_function	Create a force function from its position transfer matrix.
force_from_impedance	Create a force function from its impedance.
force_from_waves	Create a force function from waves excitation coefficients.
inertia	Create the inertia "force" from the inertia matrix.
standard_forces	Create functions for linear hydrodynamic forces.
run_bem	Run Capytaine for a range of frequencies and wave directions.
change_bem_convention	Change the convention from \(-iωt\) to \(+iωt\).
add_linear_friction	Add linear friction to BEM data.
wave_excitation	Calculate the complex, frequency-domain, excitation force due to waves.
hydrodynamic_impedance	Calculate hydrodynamic intrinsic impedance.
atleast_2d	Ensure an array is at least 2D, otherwise add trailing dimensions to make it 2D.
degrees_to_radians	Convert a 1D array of angles in degrees to radians in the range \([-π, π)\) and optionally sort them.
subset_close	Check if the first set set_a is contained, to some tolerance, in the second set set_b.
scale_dofs	Create a scaling vector based on a different scale for each DOF.
decompose_state	Split the state vector into the WEC dynamics state and the optimization (control) state.
frequency_parameters	Return the fundamental frequency and the number of frequencies in a frequency array.
time_results	Create a xarray.DataArray of time-domain results from xarray.DataArray of frequency-domain results.
set_fb_centers	Sets default properties if not provided by the user: - center_of_mass is set to the geometric centroid - rotation_center is set to the center of mass