double SQPInternal::quad_form(const std::vector<double>& x, const DMatrix& A){
// Assert dimensions
casadi_assert(x.size()==A.size1() && x.size()==A.size2());
// Access the internal data of A
const std::vector<int> &A_rowind = A.rowind();
const std::vector<int> &A_col = A.col();
const std::vector<double> &A_data = A.data();
// Return value
double ret=0;
// Loop over the rows of A
for(int i=0; i<x.size(); ++i){
// Loop over the nonzeros of A
for(int el=A_rowind[i]; el<A_rowind[i+1]; ++el){
// Get column
int j = A_col[el];
// Add contribution
ret += x[i]*A_data[el]*x[j];
}
}
return ret;
}
inline
/** \brief . */
const DVectorSlice col(const DMatrix& gm, BLAS_Cpp::Transp trans, size_type j) {
return (trans == BLAS_Cpp::no_trans) ? gm.col(j) : gm.row(j);
}
inline
/** \brief . */
DVectorSlice row(DMatrix& gm, BLAS_Cpp::Transp trans, size_type i) {
return (trans == BLAS_Cpp::no_trans) ? gm.row(i) : gm.col(i);
}