Method addMatrixVector

SRC/matrix/Vector.cpp:328–455

	    
	
int
Vector::addMatrixVector(double thisFact, const Matrix &m, const Vector &v, double otherFact )
{
  // see if quick return
  if (thisFact == 1.0 && otherFact == 0.0)
    return 0;

  // check the sizes are compatible
#ifdef _G3DEBUG
  // check the sizes are compatible
  if ((sz != m.noRows()) && (m.noCols() != v.sz)) {
    // otherwise incompatible sizes
    opserr << "Vector::addMatrixVector() - incompatible sizes\n";
    return -1;    
  }
#endif

  if (thisFact == 1.0) {

    // want: this += m * v * otherFact
    if (otherFact == 1.0) { // no point doing multiplication if otherFact = 1.0
      int otherSize = v.sz;
      double *matrixDataPtr = m.data;
      double *otherDataPtr = v.theData;
      for (int i=0; i<otherSize; i++) {
	double otherData = *otherDataPtr++;
	for (int j=0; j<sz; j++)
	  theData[j] += *matrixDataPtr++ * otherData;
      }
    } 
    else if (otherFact == -1.0) { // no point doing multiplication if otherFact = -1.0
      int otherSize = v.sz;
      double *matrixDataPtr = m.data;
      double *otherDataPtr = v.theData;
      for (int i=0; i<otherSize; i++) {
	double otherData = *otherDataPtr++;
	for (int j=0; j<sz; j++)
	  theData[j] -= *matrixDataPtr++ * otherData;
      }
    } 
    else { // have to do the multiplication
      int otherSize = v.sz;
      double *matrixDataPtr = m.data;
      double *otherDataPtr = v.theData;
      for (int i=0; i<otherSize; i++) {
	double otherData = *otherDataPtr++ * otherFact;
	for (int j=0; j<sz; j++)
	  theData[j] += *matrixDataPtr++ * otherData;
      }
    }
  }

  else if (thisFact == 0.0) {
    
    // want: this = m * v * otherFact
    for (int i=0; i<sz; i++)
      theData[i] = 0.0;