inline void SVDIncompleteIncrementalLearning::
WUpdate<arma::sp_mat>(const arma::sp_mat& V,
arma::mat& W,
const arma::mat& H)
{
arma::mat deltaW(n, W.n_cols);
deltaW.zeros();
for(arma::sp_mat::const_iterator it = V.begin_col(currentUserIndex);
it != V.end_col(currentUserIndex);it++)
{
double val = *it;
size_t i = it.row();
deltaW.row(i) += (val - arma::dot(W.row(i), H.col(currentUserIndex))) *
arma::trans(H.col(currentUserIndex));
if(kw != 0) deltaW.row(i) -= kw * W.row(i);
}
W += u*deltaW;
}
inline void SVDIncompleteIncrementalLearning::
HUpdate<arma::sp_mat>(const arma::sp_mat& V,
const arma::mat& W,
arma::mat& H)
{
arma::mat deltaH(H.n_rows, 1);
deltaH.zeros();
for(arma::sp_mat::const_iterator it = V.begin_col(currentUserIndex);
it != V.end_col(currentUserIndex);it++)
{
double val = *it;
size_t i = it.row();
if((val = V(i, currentUserIndex)) != 0)
deltaH += (val - arma::dot(W.row(i), H.col(currentUserIndex))) *
arma::trans(W.row(i));
}
if(kh != 0) deltaH -= kh * H.col(currentUserIndex);
H.col(currentUserIndex++) += u * deltaH;
currentUserIndex = currentUserIndex % m;
}
