public void Visit(Compiled.Sigmoid elem)
{
Debug.Assert(ArgumentIndex == 0 || ArgumentIndex == 1);
double e = Math.Exp(elem.Steepness * (ValueOf(elem.Mid) - ValueOf(elem.Arg)));
//Console.WriteLine("e: {0} deriv: {1}",e,elem.Derivative);
if (Double.IsPositiveInfinity(e) || e == 0)
{
if (ArgumentIndex == 0)
{
LocalDerivative = elem.Steepness * elem.Adjoint * Epsilon;
}
else
{
LocalDerivative = -elem.Steepness * elem.Adjoint * Epsilon;
}
}
else
if (ArgumentIndex == 0)
{
LocalDerivative = elem.Steepness * elem.Adjoint * e / ((e + 1) * (e + 1));
if (Math.Abs(LocalDerivative) < Math.Abs(elem.Steepness * elem.Adjoint * Epsilon))
{
LocalDerivative = elem.Steepness * elem.Adjoint * Epsilon;
}
}
else
{
LocalDerivative = -elem.Steepness * elem.Adjoint * e / ((e + 1) * (e + 1));
if (Math.Abs(LocalDerivative) < Math.Abs(elem.Steepness * elem.Adjoint * Epsilon))
{
LocalDerivative = -elem.Steepness * elem.Adjoint * Epsilon;
}
}
}
public int Visit(Sigmoid sigmoid)
{
return(Compile(sigmoid, () =>
{
var argIndex = sigmoid.Arg.Accept(this);
var midIndex = sigmoid.Mid.Accept(this);
var element = new Compiled.Sigmoid
{
Arg = argIndex,
Mid = midIndex,
Steepness = sigmoid.Steepness,
Inputs = new Compiled.InputEdge[]
{
new Compiled.InputEdge {
Index = argIndex
},
new Compiled.InputEdge {
Index = midIndex
},
}
};
return element;
}));
}
public void Visit(Compiled.Sigmoid elem)
{
double arg = ValueOf(elem.Arg);
double mid = ValueOf(elem.Mid);
double e = Math.Exp(elem.Steepness * (-arg + mid));
if (Double.IsPositiveInfinity(e))
{
elem.Value = Term.Epsilon;
}
else
{
elem.Value = 1.0 / (1.0 + e);
}
if (elem.Value < Term.Epsilon)
{
elem.Value = Term.Epsilon;
}
if (e == 0.0 || Double.IsPositiveInfinity(e))
{
elem.Inputs[0].Weight = elem.Steepness * Term.Epsilon;
elem.Inputs[1].Weight = -elem.Steepness * Term.Epsilon;
return;
}
double e2 = elem.Steepness * e / ((e + 1) * (e + 1));
elem.Inputs[0].Weight = e2;
elem.Inputs[1].Weight = -e2;
}
public void Visit(Compiled.Sigmoid elem)
{
double e = Math.Exp(elem.Steepness * (-ValueOf(elem.Arg) + ValueOf(elem.Mid)));
if (Double.IsPositiveInfinity(e))
{
elem.Value = Term.Epsilon;
//Console.WriteLine("FUCKUP {0}",e);
}
else
{
elem.Value = 1.0 / (1.0 + e);
}
if (elem.Value < Term.Epsilon)
{
elem.Value = Term.Epsilon;
}
}
public int Visit(LinSigmoid sigmoid)
{
return(Compile(sigmoid, () =>
{
var argIndex = sigmoid.Arg.Accept(this);
var element = new Compiled.Sigmoid
{
Arg = argIndex,
Inputs = new Compiled.InputEdge[]
{
new Compiled.InputEdge {
Index = argIndex
},
}
};
return element;
}));
}
