public void ApplyWeightAdjustments_PropogatesThroughNetwork()
{
//// SETUP
const double ErrorSignal = -2.3d;
const float Momentum = 0.9f;
const float LearningRate = 0.1f;
// Create 2 inbound and 2 outbound mock connections.
var mockInbound1 = new Mock<ISupervisedLearnerConnection>();
var mockInbound2 = new Mock<ISupervisedLearnerConnection>();
var mockOutbound1 = new Mock<ISupervisedLearnerConnection>();
var mockOutbound2 = new Mock<ISupervisedLearnerConnection>();
// program the mock outbounds such that both are reporting error signals
mockOutbound1.SetupGet(mock => mock.IsReportingError).Returns(true);
mockOutbound2.SetupGet(mock => mock.IsReportingError).Returns(true);
// Create 2 input nodes and 2 output nodes.
var mockInputNode1 = new Mock<ISupervisedLearnerNode>();
var mockInputNode2 = new Mock<ISupervisedLearnerNode>();
var mockOutputNode1 = new Mock<ISupervisedLearnerNode>();
var mockOutputNode2 = new Mock<ISupervisedLearnerNode>();
// Program nodes to report input/output sizes.
mockInputNode1.SetupGet(mock => mock.InputSize).Returns(1);
mockInputNode2.SetupGet(mock => mock.InputSize).Returns(1);
mockOutputNode1.SetupGet(mock => mock.OutputSize).Returns(1);
mockOutputNode2.SetupGet(mock => mock.OutputSize).Returns(1);
// Program nodes to provide values.
mockInputNode1.SetupGet(mock => mock.CachedErrors).Returns(new[] { ErrorSignal });
mockInputNode2.SetupGet(mock => mock.CachedErrors).Returns(new[] { ErrorSignal });
mockOutputNode1.SetupGet(mock => mock.CachedOutputs).Returns(new[] { 0.0d });
mockOutputNode2.SetupGet(mock => mock.CachedOutputs).Returns(new[] { 0.0d });
// Create the test object.
var network = new BackpropagationNetwork(new Mock<IErrorCalculator>().Object);
network.AddInboundConnection(mockInbound1.Object);
network.AddInboundConnection(mockInbound2.Object);
network.AddOutboundConnection(mockOutbound1.Object);
network.AddOutboundConnection(mockOutbound2.Object);
network.AddInputNode(mockInputNode1.Object);
network.AddInputNode(mockInputNode2.Object);
network.AddOutputNode(mockOutputNode1.Object);
network.AddOutputNode(mockOutputNode2.Object);
network.Fire(new[] { 0.0d });
network.CalculateError(ErrorSignal);
// EXECUTION
network.ApplyWeightAdjustments(LearningRate, Momentum);
// VERIFICATION
mockInputNode1.Verify(mock => mock.ApplyWeightAdjustments(LearningRate, Momentum), Times.Once());
mockInputNode2.Verify(mock => mock.ApplyWeightAdjustments(LearningRate, Momentum), Times.Once());
mockOutbound1.Verify(mock => mock.ApplyWeightAdjustments(LearningRate, Momentum), Times.Once());
mockOutbound2.Verify(mock => mock.ApplyWeightAdjustments(LearningRate, Momentum), Times.Once());
}
