bool InvertMatrix(A2D<ID_T>& vData)
{
ID_T d;
A2D<ID_T> vTmp(vData.Rows(),vData.Cols());
int i,j;
for(i=0;i<vData.Rows();i++)
for(j=0;j<vData.Cols();j++)
vTmp[i][j]=vData[i][j];
int N = vData.Rows();
vector<int> indx(N);
vector<ID_T> col(vData.Cols());
if(!NR::ludcmp(vTmp,indx,d))//Decompose the matrix just once.
{ Write2Log("Couldn't invert matrix!");
return false;
}
for(j=0;j<N;j++)
{ //Find inverse by columns.
for(i=0;i<N;i++)
col[i]=0.0;
col[j]=1.0;
NR::lubksb(vTmp,indx,&col[0]);
for(i=0;i<N;i++)
vData[i][j]=col[i];
}
return true;
}
//gets the inverse of the covariance matrix for a cluster
//input vFloat has each row as a data vector, each column as a dimension, to get data vector i do vFloat[i*iCols]
//bool Clust2CovarMatInv(vector<vector< ID_T > >& vCovarMat,vector<ID_T>& vMean, vector<int>& vClustIDs,int iClustID,vector<double>& vFloat,int iRows,int iCols,int& iClustSz)
bool Clust2CovarMatInv(A2D< ID_T >& vCovarMat,vector<ID_T>& vMean, vector<int>& vClustIDs,int iClustID,vector<double>& vFloat,int iRows,int iCols,int& iClustSz)
{
int i = 0, j = 0;
iClustSz = count(vClustIDs.begin(),vClustIDs.end(),iClustID);
if(!iClustSz)
return false;
A2D<double> vClustData(iClustSz,iCols);
vClustData.Fill(0.0);
for(i=0;i<iRows;i++)
if(vClustIDs[i]==iClustID)
copy(&vFloat[i*iCols],&vFloat[i*iCols+iCols],vClustData[j++]);
Write2LogPlain("clust %d sz=%d\n",iClustID,iClustSz);
CovarMat(vClustData,iClustSz,iCols,vCovarMat,vMean);
if(false){
Write2LogPlain("clust %d covar mat %dX%d\n",iClustID,vCovarMat.Rows(),vCovarMat.Cols());
for(i=0;i<vCovarMat.Rows();i++){
for(j=0;j<vCovarMat.Cols();j++){
Write2LogPlain("%g ",vCovarMat[i][j]);
}
Write2LogPlain("\n");
}
}
#ifdef _DEBUG
A2D<ID_T> mtmp(vCovarMat);
bool b = InvertMatrix(vCovarMat);
Write2LogPlain("inv covar mat");
for(i=0;i<vCovarMat.Rows();i++){
for(j=0;j<vCovarMat.Cols();j++){
Write2LogPlain("%g ",vCovarMat[i][j]);
}
Write2LogPlain("\n");
}
A2D<ID_T> vident;
MatMult(mtmp,vCovarMat,vident);
Write2LogPlain("is this identity matrix?");
for(i=0;i<vident.Rows();i++){
for(j=0;j<vident.Cols();j++){
Write2LogPlain("%g ",vident[i][j]);
}
Write2LogPlain("\n");
}
return b;
#else
return InvertMatrix(vCovarMat);
#endif
}
void MatMult(A2D<ID_T>& a, A2D<ID_T>& b,A2D<ID_T>& out)
{ int iRowsA = 0, iColsA = 0, iRowsB = 0 , iColsB = 0;
try
{
iRowsA = a.Rows(); if(!iRowsA) return; iColsA = a.Cols();
iRowsB = b.Rows(); if(!iRowsB) return; iColsB = b.Cols();
if(iColsA!=iRowsB)
return;
out.Init(iRowsA,iColsB); out.Fill(0.0);
int i,j,k;
for(i=0;i<iRowsA;i++)
for(j=0;j<iColsB;j++)
for(k=0;k<iColsA;k++)
out[i][j] += a[i][k] * b[k][j];
}
catch(...)
{
Write2Log("Exception in MatMult iRowsA=%d iColsA=%d iRowsB=%d iColsB=%d",iRowsA,iColsA,iRowsB,iColsB);
}
}