public (FloatArray dhprev, FloatArray dcprev) Backward(FloatArray dh, FloatArray dcnext, FloatArray cprev, FloatArray fGate, FloatArray iGate, FloatArray cGate, FloatArray cellState, FloatArray oGate)
{
// Set outputs
F.Output = fGate;
I.Output = iGate;
C.Output = cGate;
O.Output = oGate;
// cell State Derivate
var cellStateAct = cellState.Tanh();
var cellStateDer = (1 - cellStateAct * cellStateAct);
// cell state gradient
var dcellSate = dcnext.Clone();
dcellSate += dh * oGate * cellStateDer;
// output gate gradient
var doGate = O.BackWard(dh * cellStateAct);
// cell gate gradient
var dcGate = C.BackWard(dcellSate * iGate);
// input gate gradient
var diGate = I.BackWard(dcellSate * cGate);
// forget gate gradient
var dfGate = F.BackWard(dcellSate * cprev);
// lstm next
var dz = (F.Weights * dfGate).SumLine() + (I.Weights * diGate).SumLine() + (C.Weights * dcGate).SumLine() + (O.Weights * doGate).SumLine();
// dhPrev, cprev
return(dz, fGate *dcellSate);
}
private FloatArray Tanh(FloatArray x)
{
return(x.Tanh());
}
public static FloatArray Tanh(FloatArray x)
{
return(x.Tanh());
}
public FloatArray Activate(FloatArray sum)
{
return(sum.Tanh());
}
