## Description

Base interface class for eigensolvers for the damped dynamic problem ie.

the quadratic eigenvalue problem (lambda^2*M + lambda*R + K)*x = 0 also (-w^2*M + i*w*R + K)*x = 0, with complex w (where w.length() = undamped nat.freq) Children classes can implement this in different ways, overridding Solve()

#include <ChEigenvalueSolver.h> [legend]

## Public Member Functions

virtual bool Solve (const ChSparseMatrix &M, const ChSparseMatrix &R, const ChSparseMatrix &K, const ChSparseMatrix &Cq, ChMatrixDynamic< std::complex< double >> &V, ChVectorDynamic< std::complex< double >> &eig, ChVectorDynamic< double > &freq, ChVectorDynamic< double > &damping_ratio, ChEigenvalueSolverSettings settings=0) const =0
Solve the quadratic eigenvalue problem (lambda^2*M + lambda*R + K)*x = 0 s.t. More...

## ◆ Solve()

 virtual bool chrono::modal::ChQuadraticEigenvalueSolver::Solve ( const ChSparseMatrix & M, const ChSparseMatrix & R, const ChSparseMatrix & K, const ChSparseMatrix & Cq, ChMatrixDynamic< std::complex< double >> & V, ChVectorDynamic< std::complex< double >> & eig, ChVectorDynamic< double > & freq, ChVectorDynamic< double > & damping_ratio, ChEigenvalueSolverSettings settings = 0 ) const
pure virtual

Solve the quadratic eigenvalue problem (lambda^2*M + lambda*R + K)*x = 0 s.t.

Cq*x = 0 If n_modes=0, return all eigenvalues, otherwise only the first lower n_modes.

Parameters
 M input M matrix R input R matrix K input K matrix Cq input Cq matrix of constraint jacobians V output matrix with eigenvectors as columns, will be resized eig output vector with eigenvalues (real part not zero if some damping), will be resized freq output vector with n undamped frequencies [Hz], as f=w/(2*PI), will be resized. damping_ratio output vector with n damping rations r=damping/critical_damping. settings optional: settings for the solver, or n. of desired lower eigenvalues. If =0, return all eigenvalues.

The documentation for this class was generated from the following file:
• /builds/uwsbel/chrono/src/chrono_modal/ChEigenvalueSolver.h