LLSSolver.h

Go to the documentation of this file.

#ifndef LLSSOLVER_H
#define LLSSOLVER_H

#ifdef SINGLE
#define real float
#else
#define real double
#endif

#define max(x,y) ((x)>(y)?(x):(y))
#define min(x,y) ((x)<(y)?(x):(y))

extern "C" {

  // these subroutines are from laint.f
  // which invokes the Lapack library

#ifdef SINGLE
void  ssvd_(real *G,real *U,real *V,int *M,int *N,
            real *W,real *WORK,int *LWORK,int *INFO);
void  ssol_(real *U,real *W,real *V,int *M,int *N,
            real *rhs,real *aa,real *tmp);
#else
void  dsvd_(real *G,real *U,real *V,int *M,int *N,
            real *W,real *WORK,int *LWORK,int *INFO);
void  dsol_(real *U,real *W,real *V,int *M,int *N,
            real *rhs,real *aa,real *tmp);
#endif
}

#include <iostream>
#include <string>
#include <cmath>
#include <ctime>
#include <vector>
#include <stdlib.h>
using namespace std;

class LLSSolver {
  
 public:

  LLSSolver();

  void solve(int matrixSizeM, 
             int matrixSizeN,  
             real *A,  
             real *b,  
             real *x, 
             vector<real> &UFixedParticles, 
             vector<real> &SFixedParticles, 
             vector<real> &VFixedParticles, 
             int &fixedParticles 
             ); 

  ~LLSSolver();

 private: 
  //  void initialize(int matrixSizeM, int matrixSizeN);

  void calculateUSV(real *);

  real * allocate1dArray(int size);

  void delete1dArray(real * x);
  void releaseMemory();
 
  // matrix A has the size m x n
  // where m is the number of rows, 
  //         or the number of total pressure and vorticity points
  //         or the number of equations
  // n is the number of columns
  //         or the number of undetermined coefficients
  //            for velocity, etc.
  int m, n;
  int i, j, iter;

  int nIter;

  // use convention A = U*S*V'
  // U with size M by M
  // V with size V by V
  // S with size M by N

  // but in the lapack library, S has the dimension min(M, N)
  // S is the singular values of A
  // so, here we use the convention from lapack
  // tmp is only used for a temporary purpose
  real *U, *V, *S, *tmp;


};

#endif

---