/// Call this function after you have added all the layers.
/// It adds an extra output layer.
int ANN_Init(ANN * ann)
{
// Add output layer
LISTITEM *item = LastListItem(ann->c);
Layer *l = NULL;
#ifdef ANN_DBUG
message("Initialising");
#endif
if (item) {
Layer *p = (Layer *) item->obj;
l = ANN_AddLayer(ann, p->n_outputs, ann->n_outputs, p->y);
} else {
l = ANN_AddLayer(ann, ann->n_inputs, ann->n_outputs,
ann->x);
}
if (l == NULL) {
Serror("Could not create final layer\n");
DeleteANN(ann);
return -1;
}
ann->y = l->y;
l->f = &linear;
l->f_d = &linear_d;
// ann->t = l->t;
return 0;
}
/// Save the ANN to a C file handle.
int SaveANN(ANN* ann, FILE* f)
{
if (f==NULL) {
return -1;
}
StringBuffer* rtag = NewStringBuffer (256);
WriteToken("VSOUND_ANN", f);
fwrite(&ann->n_inputs, sizeof(int), 1, f);
fwrite(&ann->n_outputs, sizeof(int), 1, f);
WriteToken("Layer Data", f);
int n_layers = 0;
LISTITEM* list_item = FirstListItem(ann->c);
while (list_item) {
n_layers++;
list_item = NextListItem (ann->c);
}
fwrite(&n_layers, sizeof(int), 1, f);
list_item = FirstListItem(ann->c);
for (int i=0; i<n_layers-1; i++) {
Layer* l = (Layer*) list_item->obj;
int layer_type = 0;
WriteToken("TYPE", f);
fwrite(&layer_type, sizeof(int), 1, f);
int nhu = l->n_outputs;
WriteToken("UNITS", f);
fwrite(&nhu, sizeof(int), 1, f);
list_item = NextListItem (ann->c);
}
WriteToken("Output Type", f);
{
int layer_type = 0;
LISTITEM *c;
c = LastListItem(ann->c);
if (c) {
Layer *l = (Layer *) c->obj;
if (l->f==&linear) {
layer_type = 0;
} else {
layer_type = 1;
}
}
fwrite(&layer_type, sizeof(int), 1, f);
}
list_item = FirstListItem(ann->c);
while(list_item) {
Layer* l = (Layer*) list_item->obj;
WriteToken("Connections", f);
int size = (l->n_inputs + 1 /*bias*/) * l->n_outputs;
fwrite(l->c, size, sizeof(Connection), f);
list_item = NextListItem(ann->c);
}
WriteToken("END", f);
FreeStringBuffer (&rtag);
return 0;
}
//==========================================================
// ANN_SetOutputsToTanH()
//----------------------------------------------------------
/// Set outputs to hyperbolic tangent.
void ANN_SetOutputsToTanH(ANN * ann)
{
LISTITEM *c;
c = LastListItem(ann->c);
if (c) {
Layer *l = (Layer *) c->obj;
l->f = &htan;
l->f_d = &htan_d;
} else {
Serror("Could not set outputs to TanH\n");
}
}
//==========================================================
// ANN_SetOutputsToLinear()
//----------------------------------------------------------
/// Set outputs to linear
void ANN_SetOutputsToLinear(ANN * ann)
{
LISTITEM *c;
c = LastListItem(ann->c);
if (c) {
Layer *l = (Layer *) c->obj;
l->f = &linear;
l->f_d = &linear_d;
} else {
Serror("Could not set outputs to linear\n");
}
}
//==========================================================
// ANN_AddRBFHiddenLayer()
//----------------------------------------------------------
/// Add an RBF layer with n_nodes
int ANN_AddRBFHiddenLayer(ANN * ann, int n_nodes)
{
#ifdef ANN_DBUG
message("Adding Hidden layer with %d nodes", n_nodes);
#endif
LISTITEM *item = LastListItem(ann->c);
if (item) {
Layer *p = (Layer *) item->obj;
ANN_AddRBFLayer(ann, p->n_outputs, n_nodes, p->y);
} else {
ANN_AddRBFLayer(ann, ann->n_inputs, n_nodes, ann->x);
}
return 0;
}
/// The argument delta is a the derivative of the cost function with
/// respect to the neural network outputs. In this case you must call
/// ANN_Input() yourself. As an example, to use MSE cost with
/// ANN_Delta_Train(), you should call ANN_Input() with your data,
/// call ANN_GetOutput() to take a look at the outputs and then call
/// ANN_DeltaTrain() with a real vector delta equal to the target
/// vector minus the ANN output vector. The argument TD is useful if
/// you want to separate the calculation of the derivative of the
/// output with respect to the parameters from the derivative the cost
/// function with respect to the output. This is done in reinforcement
/// learning with eligibility traces for example, where the cost
/// function depends upon previous outputs.
real ANN_Delta_Train(ANN * ann, real* delta, real TD)
{
LISTITEM *p = LastListItem(ann->c);
Layer *l = (Layer *) p->obj;
real sum = 0.0f;
int j;
//ANN_Input(ann, x);
for (j = 0; j < ann->n_outputs; j++) {
real f = l->f_d(ann->y[j]);
real e = delta[j];
ann->error[j] = e;
ann->d[j] = e * f;
sum += e * e;
}
l->backward(p, ann->d, ann->eligibility_traces, TD);
return sum;
}