// convertion
void mat2Blob(mat& mA, shared_ptr<Blob>& out, int c, int h, int w) {
int n = mA.n_rows;
assert(mA.n_cols == c*h*w);
mA = mA.t();
if (out) {
out.reset();
}
out.reset(new Blob(n, c, h, w));
for (int i = 0; i < n; ++i) {
(*out)[i] = cube(mA.colptr(i), h, w, c);
}
return;
}
void update(const record & rcd) {
unsigned int i = rcd.user - 1, j = rcd.movie - 1;
double r_pFpX;
double *Ui = U.colptr(i);
double *Vj = V.colptr(j);
double UiVj = fang_mul(Ui, Vj, K);
r_pFpX = learning_rate_per_record * 2.0 * (rcd.score - mu - (UiVj + A(i) + B(j)));
// U(:,i) = U(:,i) - rate * gUi; gUi = - pFpX * V(:,j);
fang_add_mul(Ui, Vj, r_pFpX, K);
// V(:,j) = V(:,j) - rate * gVj; gVj = - pFpX * U(:,i);
fang_add_mul(Vj, Ui, r_pFpX, K);
// A(:,i) = A(:,i) - rate * gAi; gAi = - pFpX;
A(i) += r_pFpX;
// B(:,j) = B(:,j) - rate * gBj; gBj = - pFpX;
B(j) += r_pFpX;
}
void mat2Blob(mat& mA, shared_ptr<Blob>& out, const vector<int>& sz) {
int n = mA.n_rows;
int c = sz[1];
int h = sz[2];
int w = sz[3];
assert(mA.n_cols == c*h*w);
mA = mA.t();
if (out) {
out.reset();
}
out.reset(new Blob(n, c, h, w));
for (int i = 0; i < n; ++i) {
(*out)[i] = cube(mA.colptr(i), h, w, c);
}
return;
}