Beispiel #1
0
int main(int argc, char*argv[])
{
    MatrixXd a(3, 4) ,b(3,4);
    vector<MatrixXd> ZE;
    a << 1,2,3,4,5,6,7,8,9,10,11,12;
    b << 13,14,15,16,17,18,19,20,21,22,23,24;

    double lambda=0.02;
    LowRankRepresentation lrr(a, b, lambda);
    ZE = lrr.result(a, b, lambda);
    cout << "Z = " << endl << ZE[0] <<endl;
    cout << "E = " << endl << ZE[1] <<endl;
    return 0;
}
Beispiel #2
0
 /* Always include this */
void mexFunction(int nlhs, mxArray *plhs[],                       /* Output variables */
                          int nrhs, const mxArray *prhs[])             /* Input variables */
{

if(nrhs < 1 || nrhs > 3)                /* Check the number of arguments */
     mexErrMsgTxt("Wrong number of input arguments.");
else if(nlhs > 2)
     mexErrMsgTxt("Too many output arguments.");
/* if (nrhs == 2)                     
     lambda = 0.02;
else
     lambda = prhs[2];
*/

double *X, *D,*Z,*E,lambda;
int XM, XN,DM,DN, ZM,ZN,m, n;

lambda = mxGetScalar(lambda_IN);                         /* Get lambda */

X = mxGetPr(X_IN);                                                /* Get the pointer to  the data of X */
XM = mxGetM(X_IN);                                              /* Get the dimensions  of X */
XN = mxGetN(X_IN);

D = mxGetPr(D_IN);                                               
DM = mxGetM(D_IN);                                            
DN = mxGetN(D_IN);

ZM = DN;
ZN =  XN;
m=0,n=0;
//X[m + M*n]

MatrixXd x(XM, XN) ,d(DM,DN),z(ZM,ZN);

vector<MatrixXd> ze;

Z_OUT = mxCreateDoubleMatrix(DN, XN, mxREAL);
Z = mxGetPr(Z_OUT);                                             /* Get the pointer to  the data of Z */
E_OUT = mxCreateDoubleMatrix(DN, XN, mxREAL);
E = mxGetPr(E_OUT);

//cout << "ZM" << ZM << "ZN" << ZN << endl;;

for (n=0;n<XN;n++)
    for(m=0;m<XM;m++)
        x(m,n) = X[m+ZM*n];


for (n=0;n<DN;n++)
    for(m=0;m<DM;m++)
        d(m,n) = D[m+ZM*n];


LowRankRepresentation lrr(x, d, lambda);
ze = lrr.result(x, d, lambda);



for (n=0;n<ZN;n++)
    for(m=0;m<ZM;m++)
        Z[m+ZM*n] = ze[0](m,n);

for (n=0;n<ZN;n++)
    for(m=0;m<ZM;m++)
        E[m+ZM*n] = ze[1](m,n);

//Z = ZE[0]; 
//E = ZE[1];
        
        
//mexPrintf("Hello, world!\n");                                   /* Do something interesting */
return;
}
void Tri2dFCBlockSolver::gradSetupQuadratic()
{
  // form quadratic sub elements
  int nElemQ = 3*nElem;
  int nneQ   = 6; //quadratic elements
  int nngQ   = 4; //quadratic elements
  Array2D<int> elemQ(nElemQ,nneQ),gNode(nElemQ,nngQ);
  int m=0;
  for (int n=0; n<nElem; n++){
    elemQ(m  ,0) = elem(n,0);
    elemQ(m  ,1) = elem(n,4);
    elemQ(m  ,2) = elem(n,7);
    elemQ(m  ,3) = elem(n,3);
    elemQ(m  ,4) = elem(n,9);
    elemQ(m  ,5) = elem(n,8);
    gNode(m  ,0) = 0;
    gNode(m  ,1) = 3;
    gNode(m  ,2) = 4;
    gNode(m++,3) = 5;
    elemQ(m  ,0) = elem(n,3);
    elemQ(m  ,1) = elem(n,1);
    elemQ(m  ,2) = elem(n,6);
    elemQ(m  ,3) = elem(n,4);
    elemQ(m  ,4) = elem(n,5);
    elemQ(m  ,5) = elem(n,9);
    gNode(m  ,0) = 1;
    gNode(m  ,1) = 4;
    gNode(m  ,2) = 5;
    gNode(m++,3) = 3;
    elemQ(m  ,0) = elem(n,8);
    elemQ(m  ,1) = elem(n,5);
    elemQ(m  ,2) = elem(n,2);
    elemQ(m  ,3) = elem(n,9);
    elemQ(m  ,4) = elem(n,6);
    elemQ(m  ,5) = elem(n,7);
    gNode(m  ,0) = 2;
    gNode(m  ,1) = 5;
    gNode(m  ,2) = 3;
    gNode(m++,3) = 4;
  }

  /*
  for (int n=0; n<nElemQ; n++){
    cout << n << " ";
    for (int j=0; j<nneQ; j++) cout << elemQ(n,j) << " ";
    cout << endl;
  }
  exit(0);
  */


  // Jacobian terms
  Array2D <double> xr(nElemQ,nngQ),yr(nElemQ,nngQ),xs(nElemQ,nngQ),
    ys(nElemQ,nngQ),jac(nElemQ,nngQ),rs(nneQ,3),lc(nneQ,nneQ);
  xr.set(0.);
  yr.set(0.);
  xs.set(0.);
  ys.set(0.);
  jac.set(0.);

  int orderE=2; //quadratic elements 
  solutionPoints(orderE,
		 spacing,
		 &rs(0,0));

  bool test=true;
  lagrangePoly(test,
	       orderE,
	       &rs(0,0),
	       &lc(0,0));

  int j,km,lm;
  double lrm,lsm,ri,si;
  for (int n=0; n<nElemQ; n++){

    // evaluate the Jacobian terms at the mesh points
    for (int i=0; i<nngQ; i++){ //ith mesh point
      ri = rs(gNode(n,i),0);
      si = rs(gNode(n,i),1);
      for (int m=0; m<nneQ; m++){ //mth Lagrange polynomial
	j   = 0;
	lrm = 0.;
	lsm = 0.;
	for (int k=0; k<=orderE; k++)
	  for (int l=0; l<=orderE-k; l++){
	    km   = max(0,k-1);
	    lm   = max(0,l-1);
	    lrm +=((double)k)*pow(ri,km)*pow(si,l )*lc(m,j  );
	    lsm +=((double)l)*pow(ri,k )*pow(si,lm)*lc(m,j++);
	  }
	xr(n,i) += lrm*x(elemQ(n,m),0);
	yr(n,i) += lrm*x(elemQ(n,m),1);
	xs(n,i) += lsm*x(elemQ(n,m),0);
	ys(n,i) += lsm*x(elemQ(n,m),1);
      }
      jac(n,i) = xr(n,i)*ys(n,i)-yr(n,i)*xs(n,i);
    }}


  // lr(i,j) = (dl_j/dr)_i (a row is all Lagrange polynomials (derivatives)
  // evaluated at a single mesh point i, same with the other derivatives)
  Array2D<double> lr(nneQ,nneQ),ls(nneQ,nneQ),lrr(nneQ,nneQ),
    lss(nneQ,nneQ),lrs(nneQ,nneQ);
  lr.set(0.);
  ls.set(0.);
  lrr.set(0.);
  lss.set(0.);
  lrs.set(0.);
  int kmm,lmm;
  for (int n=0; n<nneQ; n++) // nth Lagrange polynomial
    for (int i=0; i<nneQ; i++){ // ith mesh point
      j  = 0;
      ri = rs(i,0);
      si = rs(i,1);
      for (int k=0; k<=orderE; k++)
	for (int l=0; l<=orderE-k; l++){
	  km        = max(0,k-1);
	  lm        = max(0,l-1);
	  kmm       = max(0,k-2);
	  lmm       = max(0,l-2);
	  lr (i,n) +=((double)k)*pow(ri,km)*pow(si,l )*lc(n,j);
	  ls (i,n) +=((double)l)*pow(ri,k )*pow(si,lm)*lc(n,j);
	  lrr(i,n) +=((double)(k*km))*pow(ri,kmm)*pow(si,l  )*lc(n,j  );
	  lss(i,n) +=((double)(l*lm))*pow(ri,k  )*pow(si,lmm)*lc(n,j  );
	  lrs(i,n) +=((double)(k*l ))*pow(ri,km )*pow(si,lm )*lc(n,j++);
	}}


  // compute averaged quadratic FEM gradient coefficients
  Array1D<double> sumj(nNode);
  sumj.set(0.);
  for (int n=0; n<nElemQ; n++)
    for (int i=0; i<nngQ; i++){
      m                 = gNode(n,i);
      sumj(elemQ(n,m)) += jac(n,i);
    }
  for (int n=0; n<nNode; n++) sumj(n) = 1./sumj(n);

  int k1,k2;
  double xri,yri,xsi,ysi;
  Array2D<double> ax(nNode,2);
  ax.set(0.);
  gxQ.set(0.);
  for (int n=0; n<nElemQ; n++)
    for (int i=0; i<nngQ; i++){
      m   = gNode(n,i);
      k1  = elemQ(n,m);
      xri = xr(n,i);
      yri = yr(n,i);
      xsi = xs(n,i);
      ysi = ys(n,i);
      for (int j=0; j<nneQ; j++){
	k2       = elemQ(n,j);
	ax(k2,0) = lr(m,j)*ysi-ls(m,j)*yri;
	ax(k2,1) =-lr(m,j)*xsi+ls(m,j)*xri;
      }
      for(int j=psp2(k1); j<psp2(k1+1); j++){
	k2        = psp1(j);
	gxQ(j,0) += ax(k2,0);
	gxQ(j,1) += ax(k2,1);
      }
      for (int j=0; j<nneQ; j++){
	k2       = elemQ(n,j);
	ax(k2,0) = 0.;
	ax(k2,1) = 0.;
      }}

  for (int n=0; n<nNode; n++)
    for (int i=psp2(n); i<psp2(n+1); i++){
      gxQ(i,0) *= sumj(n);
      gxQ(i,1) *= sumj(n);
    }


  // deallocate work arrays
  elemQ.deallocate();
  gNode.deallocate();
  xr.deallocate();
  yr.deallocate();
  xs.deallocate();
  ys.deallocate();
  jac.deallocate();
  rs.deallocate();
  lc.deallocate();
  lr.deallocate();
  ls.deallocate();
  lrr.deallocate();
  lss.deallocate();
  lrs.deallocate();
  sumj.deallocate();
  ax.deallocate();
}