/// <summary> Links the given <paramref name="previousNeuron"/> to the <paramref name="nextNeuron"/> with the given <paramref name="weight"/>. </summary>
/// <param name="previousNeuron"> The <see cref="IReadOnlyNeuron"/> in the <see cref="PreviousNeuronLayer"/>. </param>
/// <param name="nextNeuron"> The <see cref="IReadOnlyNeuron"/> in the <see cref="NextNeuronLayer"/>. </param>
/// <param name="weight"> The weight to set. </param>
public void LinkNeurons(IReadOnlyNeuron previousNeuron, IReadOnlyNeuron nextNeuron, float weight)
{
#if DEBUG
ensureValid(previousNeuron, nextNeuron);
#endif
// Create the connection.
weightConnection weightConnection = new weightConnection(previousNeuron.Index, nextNeuron.Index, weight);
// Add the previous connection using the previous neuron.
if (previousNeuronConnectionsByID.TryGetValue(previousNeuron.Index, out Dictionary <uint, weightConnection> previousNeuronConnections))
{
previousNeuronConnections.Add(nextNeuron.Index, weightConnection);
}
else
{
previousNeuronConnectionsByID.Add(previousNeuron.Index, new Dictionary <uint, weightConnection>()
{
{ nextNeuron.Index, weightConnection }
});
}
// Add the next connection using the next neuron.
if (nextNeuronConnectionsByID.TryGetValue(nextNeuron.Index, out Dictionary <uint, weightConnection> nextNeuronConnections))
{
nextNeuronConnections.Add(previousNeuron.Index, weightConnection);
}
else
{
nextNeuronConnectionsByID.Add(nextNeuron.Index, new Dictionary <uint, weightConnection>()
{
{ previousNeuron.Index, weightConnection }
});
}
}
/// <summary> Gets the weight between the given <paramref name="previousNeuron"/> and <paramref name="nextNeuron"/>. </summary>
/// <param name="previousNeuron"> The <see cref="IReadOnlyNeuron"/> in the <see cref="PreviousNeuronLayer"/>. </param>
/// <param name="nextNeuron"> The <see cref="IReadOnlyNeuron"/> in the <see cref="NextNeuronLayer"/>. </param>
/// <returns> The weight between the given <paramref name="previousNeuron"/> and <paramref name="nextNeuron"/>. </returns>
public float GetWeightBetweenNeurons(IReadOnlyNeuron previousNeuron, IReadOnlyNeuron nextNeuron)
{
#if DEBUG
ensureValid(previousNeuron, nextNeuron);
#endif
return(previousNeuronConnectionsByID[previousNeuron.Index][nextNeuron.Index].Weight);
}
/// <summary> Gets the change of weight between the given <paramref name="nextNeuron"/> and <paramref name="previousNeuron"/>. </summary>
/// <param name="previousNeuron"> The neuron in the previous <see cref="NeuronLayer"/>. </param>
/// <param name="nextNeuron"> The neuron in the next <see cref="NeuronLayer"/>. </param>
/// <returns> The weight between the given <paramref name="nextNeuron"/> and <paramref name="previousNeuron"/>. </returns>
public float GetWeightChangeBetweenNeurons(IReadOnlyNeuron previousNeuron, IReadOnlyNeuron nextNeuron)
{
#if DEBUG
// Ensure the neurons are for this weight layer.
ensureValidity(previousNeuron, nextNeuron);
#endif
// Return the weight.
return(nextNeuronConnections[nextNeuron.Index][previousNeuron.Index]);
}
private void ensureValidity(IReadOnlyNeuron previousNeuron, IReadOnlyNeuron nextNeuron)
{
if (previousNeuron.NeuronLayer.NextWeightLayer != WeightLayer)
{
throw new Exception("Neuron mismatch, previous neuron is not in the expected layer.");
}
if (nextNeuron.NeuronLayer.PreviousWeightLayer != WeightLayer)
{
throw new Exception("Neuron mismatch, next neuron is not in the expected layer.");
}
}
/// <summary> Sets the delta for the given <paramref name="neuron"/> to the given <paramref name="newDelta"/>. </summary>
/// <param name="neuron"> The <see cref="IReadOnlyNeuron"/> whose delta is being set. </param>
/// <param name="newDelta"> The new value of the delta. </param>
public void SetDelta(IReadOnlyNeuron neuron, float newDelta)
{
#if DEBUG
// Ensure this is the correct layer for the given neuron.
if (neuron.NeuronLayer != NeuronLayer)
{
throw new Exception("Layer mismatch.");
}
#endif
// Set the delta.
delta[neuron.Index] = newDelta;
}
/// <summary> Adds the given <paramref name="biasChange"/> to the bias for the given <paramref name="neuron"/>. </summary>
/// <param name="neuron"> The <see cref="IReadOnlyNeuron"/> who bias is being changed. </param>
/// <param name="biasChange"> The change to the bias. </param>
public void AddBias(IReadOnlyNeuron neuron, float biasChange)
{
#if DEBUG
// Ensure this is the correct layer for the given neuron.
if (neuron.NeuronLayer != NeuronLayer)
{
throw new Exception("Layer mismatch.");
}
#endif
// Add the bias change.
biasChanges[neuron.Index] += biasChange;
}
/// <summary> Gets the change to bias for the given <paramref name="neuron"/>. </summary>
/// <param name="neuron"> The <see cref="IReadOnlyNeuron"/> whose bias change is desired. </param>
/// <returns> The change to bias for the given <paramref name="neuron"/>. </returns>
public float GetBias(IReadOnlyNeuron neuron)
{
#if DEBUG
// Ensure this is the correct layer for the given neuron.
if (neuron.NeuronLayer != NeuronLayer)
{
throw new Exception("Layer mismatch.");
}
#endif
// Return the bias change.
return(biasChanges[neuron.Index]);
}
/// <summary> Adds the given <paramref name="weightChange"/> to the connection between the given <paramref name="nextNeuron"/> and <paramref name="previousNeuron"/>. </summary>
/// <param name="previousNeuron"> The neuron in the previous <see cref="NeuronLayer"/>. </param>
/// <param name="nextNeuron"> The neuron in the next <see cref="NeuronLayer"/>. </param>
/// <param name="weightChange"> The amount of weight to change. </param>
public void AddWeightChangeBetweenNeurons(IReadOnlyNeuron previousNeuron, IReadOnlyNeuron nextNeuron, float weightChange)
{
#if DEBUG
// Ensure the neurons are for this weight layer.
ensureValidity(previousNeuron, nextNeuron);
#endif
// If there is no change to be made, do nothing.
if (weightChange == 0)
{
return;
}
// Add the weight.
nextNeuronConnections[nextNeuron.Index][previousNeuron.Index] += weightChange;
}
private void ensureValid(IReadOnlyNeuron previousNeuron, IReadOnlyNeuron nextNeuron)
{
// Ensure the given neurons are not null.
if (previousNeuron is null)
{
throw new ArgumentNullException(nameof(previousNeuron));
}
if (nextNeuron is null)
{
throw new ArgumentNullException(nameof(nextNeuron));
}
// Ensure that the layers of the given neurons match.
if (previousNeuron.NeuronLayer != PreviousNeuronLayer)
{
throw new Exception("Given previous neuron was not part of the previous layer of this weight layer.");
}
if (nextNeuron.NeuronLayer != NextNeuronLayer)
{
throw new Exception("Given next neuron was not part of the next layer of this weight layer.");
}
}
/// <summary> Gets an <see cref="IEnumerable"/> for the given <paramref name="previousNeuron"/>'s connections to the <see cref="NextNeuronLayer"/>. </summary> /// <param name="previousNeuron"></param> /// <returns></returns> public IEnumerable <uint> GetNextLayerConnections(IReadOnlyNeuron previousNeuron) => previousNeuronConnectionsByID[previousNeuron.Index].Keys.AsEnumerable();
/// <summary> Gets an <see cref="IEnumerable"/> for the given <paramref name="nextNeuron"/>'s connections to the <see cref="PreviousNeuronLayer"/>. </summary> /// <param name="nextNeuron"></param> /// <returns></returns> public IEnumerable <uint> GetPreviousLayerConnections(IReadOnlyNeuron nextNeuron) => nextNeuronConnectionsByID[nextNeuron.Index].Keys.AsEnumerable();