private static void displayImage(TrainingExample example)
{
for (int i = 1; i <= 784; ++i)
{
if (i - 1 % 28 == 0)
{
Console.Write("\n");
}
Console.Write(example.input[i, 1] + ", ");
}
Console.Write("\n");
string s = "";
for (int i = 1; i <= 784; ++i)
{
if (example.input[i, 1] == 0)
{
s += " ";
}
else if (example.input[i, 1] < 0.5F)
{
s += ".";
}
else if (example.input[i, 1] <= 1.0F)
{
s += "O";
}
if (i % 28 == 0)
{
s += "\n";
}
}
Console.WriteLine(s);
Console.WriteLine("\n\n" + example.expectedOutput[1, 1] + " " + example.expectedOutput[2, 1] + " " + example.expectedOutput[3, 1] + " " + example.expectedOutput[4, 1] + " " + example.expectedOutput[5, 1] + " " + example.expectedOutput[6, 1] + " " + example.expectedOutput[7, 1] + " " + example.expectedOutput[8, 1] + " " + example.expectedOutput[9, 1] + " " + example.expectedOutput[10, 1] + " ");
}
public static void DecimalBinaryExample()
{
int[] layers = new int[] { 2, 5, 4 };
FeedforwardNeuralNetwork fnn = new FeedforwardNeuralNetwork(layers, 1.0F, 0.1F);
DecimalBinaryTestNetwork(fnn);
Matrix[] expectedOutputs = { new Matrix(new float[4, 1] {
{ 1 },
{ 0 },
{ 0 },
{ 0 }
}),
new Matrix(new float[4, 1] {
{ 0 },
{ 1 },
{ 0 },
{ 0 }
}),
new Matrix(new float[4, 1] {
{ 0 },
{ 0 },
{ 1 },
{ 0 }
}),
new Matrix(new float[4, 1] {
{ 0 },
{ 0 },
{ 0 },
{ 1 }
}) };
Matrix[] inputs = { new Matrix(new float[2, 1] {
{ 0 },
{ 0 }
}),
new Matrix(new float[2, 1] {
{ 0 },
{ 1 }
}),
new Matrix(new float[2, 1] {
{ 1 },
{ 0 }
}),
new Matrix(new float[2, 1] {
{ 1 },
{ 1 }
}) };
TrainingExample[] examples = new TrainingExample[4];
for (int i = 0; i < 4; ++i)
{
examples[i] = new TrainingExample(inputs[i], expectedOutputs[i]);
}
fnn.TrainEpochs(examples, 1000);
DecimalBinaryTestNetwork(fnn);
}
public void Train(TrainingExample trainingExample)
{
if (trainingExample.DesiredOutputs.Length != this.OutputNodes)
{
throw new Exception("The number of output nodes and the nodes of the example doesn't match");
}
this.Query(trainingExample);
for (int i = 0; i < this.OutputNodes; i++)
{
this.OutputLayer[i].Delta = Math.Abs(this.OutputLayer[i].Value - trainingExample.DesiredOutputs[i]);
}
for (int i = this.HiddenLayers.Count; i >= 0; i--)
{
if (i == this.HiddenLayers.Count)
{
for (int j = 0; j < HiddenLayers[i - 1].Count; j++)
{
for (int k = 0; k < this.OutputNodes; k++)
{
this.HiddenLayers[i - 1][j].Delta += Math.Abs((this.HiddenLayers[i - 1][j].Value) -
(this.OutputLayer[k].Delta * this.HiddenLayers[i - 1][j].Dendrites[k].Weight));
}
}
}
else if (i == 0)
{
for (int j = 0; j < this.InputNodes; j++)
{
for (int k = 0; k < this.HiddenLayers[i].Count; k++)
{
this.InputLayer[j].Delta += Math.Abs((this.InputLayer[j].Value) -
(this.HiddenLayers[i][k].Delta * this.InputLayer[j].Dendrites[k].Weight));
}
}
}
else
{
for (int j = 0; j < HiddenLayers[i - 1].Count; j++)
{
for (int k = 0; k < this.HiddenLayers[i].Count; k++)
{
this.HiddenLayers[i - 1][j].Delta += Math.Abs((this.HiddenLayers[i - 1][j].Value) -
(this.HiddenLayers[i][k].Delta * this.HiddenLayers[i - 1][j].Dendrites[k].Weight));
}
}
}
}
}
private static TrainingExample[] GetTrainingExamples()
{
try {
Console.WriteLine("Searching for training datasets.");
FileStream labelsStream = new FileStream(@"E:\Users\Alexander Weaver\My Documents\Programs\MNIST\train-labels.idx1-ubyte", FileMode.Open);
FileStream imagesStream = new FileStream(@"E:\Users\Alexander Weaver\My Documents\Programs\MNIST\train-images.idx3-ubyte", FileMode.Open);
Console.WriteLine("Training datasets found.");
BinaryReader labelsReader = new BinaryReader(labelsStream);
BinaryReader imagesReader = new BinaryReader(imagesStream);
int magic1 = imagesReader.ReadInt32();
int numImages = (imagesReader.ReadByte() << 24) | (imagesReader.ReadByte() << 16) | (imagesReader.ReadByte() << 8) | (imagesReader.ReadByte());
int numRows = imagesReader.ReadInt32();
int numColumns = imagesReader.ReadInt32();
int magic2 = labelsReader.ReadInt32();
int numLabels = labelsReader.ReadInt32();
Console.WriteLine("Popluating training examples.");
TrainingExample[] trainingExamples = new TrainingExample[numImages];
//List<TrainingExample> trainingExamples = new List<TrainingExample>();
for (int r = 0; r < numImages; ++r)
{
Matrix input = new Matrix(784, 1);
Matrix expectedOutput = new Matrix(10, 1);
for (int i = 1; i <= 784; ++i)
{
byte b = imagesReader.ReadByte();
input[i, 1] = (float)b / (float)256;
}
int expectedNum = labelsReader.ReadByte();
if (expectedNum == 0)
{
expectedOutput[10, 1] = 1;
}
else
{
expectedOutput[expectedNum, 1] = 1;
}
trainingExamples[r] = new TrainingExample(input, expectedOutput);
/*if ((expectedNum == 2 || expectedNum == 6)) {
* trainingExamples.Add(new TrainingExample(input, expectedOutput));
* }*/
}
Console.WriteLine("Training examples populated.");
return(trainingExamples.ToArray());
} catch (Exception ex) {
Console.WriteLine(ex.ToString());
return(null);
}
}
public static void LogicGatesExample()
{
//First layer is input layer
//Initialize a 2-layer ANN
//Two inputs, one output
int[] layers = new int[] { 2, 3, 1 };
FeedforwardNeuralNetwork fnn = new FeedforwardNeuralNetwork(layers, 1.0F, 0.1F);
//Train this many cycles
int numTrainingEpochs = 10000;
TrainingExample ex1 = new TrainingExample(new Matrix(new float[, ] {
{ 0 },
{ 0 }
}),
new Matrix(new float[, ] {
{ 0 }
}));
TrainingExample ex2 = new TrainingExample(new Matrix(new float[, ] {
{ 0 },
{ 1 }
}),
new Matrix(new float[, ] {
{ 1 }
}));
TrainingExample ex3 = new TrainingExample(new Matrix(new float[, ] {
{ 1 },
{ 0 }
}),
new Matrix(new float[, ] {
{ 1 }
}));
TrainingExample ex4 = new TrainingExample(new Matrix(new float[, ] {
{ 1 },
{ 1 }
}),
new Matrix(new float[, ] {
{ 0 }
}));
TrainingExample[] trainingExamples = { ex1, ex2, ex3, ex4 };
for (int i = 0; i < numTrainingEpochs; ++i)
{
//Sets input matrices and output matrices and trains the network accordingly for all combinations
Random rand = new Random();
trainingExamples = trainingExamples.OrderBy(x => rand.Next()).ToArray();
for (int j = 0; j < 4; ++j)
{
fnn.TrainIteration(trainingExamples[j].input, trainingExamples[j].expectedOutput, 1 - (1.0F * 0.1F / 4));
}
}
//After training, evaluates the network with respect to all possible inputs
//Prints their outputs to the console to see the result of training
float[,] inputArray = new float[, ] {
{ 0 },
{ 0 }
};
Matrix input = new Matrix(inputArray);
Matrix output = fnn.Evaluate(input);
Console.WriteLine(output[1, 1]);
inputArray = new float[, ] {
{ 0 },
{ 1 }
};
input = new Matrix(inputArray);
output = fnn.Evaluate(input);
Console.WriteLine(output[1, 1]);
inputArray = new float[, ] {
{ 1 },
{ 0 }
};
input = new Matrix(inputArray);
output = fnn.Evaluate(input);
Console.WriteLine(output[1, 1]);
inputArray = new float[, ] {
{ 1 },
{ 1 }
};
input = new Matrix(inputArray);
output = fnn.Evaluate(input);
Console.WriteLine(output[1, 1]);
}
//TODO: nueron.value muest be 0 at the start of the loop/ return I think should be a bool
public bool Query(TrainingExample trainingExample)
{
if (trainingExample.InitialValues.Length != this.InputLayer.Count)
{
throw new Exception("The number of initual values and the nodes of the input layer doesn't match");
}
for (int i = 0; i < trainingExample.InitialValues.Length; i++)
{
this.InputLayer[i].Value = trainingExample.InitialValues[i];
}
for (int l = 0; l < this.HiddenLayers.Count + 1; l++)
{
//Calculates the input values for the first Hidden layer.
if (l == 0)
{
for (int i = 0; i < this.HiddenLayers[l].Count; i++)
{
this.HiddenLayers[l][i].Value = 0;
for (int j = 0; j < this.InputLayer.Count; j++)
{
this.HiddenLayers[l][i].Value += this.InputLayer[j].Value * this.InputLayer[j].Dendrites[i].Weight;
}
this.HiddenLayers[l][i].Value = SigmoidFunction(this.HiddenLayers[l][i].Value + this.HiddenLayers[l][i].Bias);
}
//Calculates the input values for the Hidden Layers except the last one.
}
else if (l == this.HiddenLayers.Count)
{
for (int i = 0; i < this.OutputNodes; i++)
{
this.OutputLayer[i].Value = 0;
for (int j = 0; j < this.HiddenLayers[l - 1].Count; j++)
{
this.OutputLayer[i].Value += this.HiddenLayers[l - 1][j].Value * this.HiddenLayers[l - 1][j].Dendrites[i].Weight;
}
this.OutputLayer[i].Value = SigmoidFunction(this.OutputLayer[i].Value + this.OutputLayer[i].Bias);
}
}
else
{
//Calculates the input values for the last Hidden Layers.
for (int i = 0; i < this.HiddenLayers[l].Count; i++)
{
this.HiddenLayers[l][i].Value = 0;
for (int j = 0; j < this.HiddenLayers[l - 1].Count; j++)
{
this.HiddenLayers[l][i].Value += this.HiddenLayers[l - 1][j].Value * this.HiddenLayers[l - 1][j].Dendrites[i].Weight;
}
this.HiddenLayers[l][i].Value = SigmoidFunction(this.HiddenLayers[l][i].Value + this.HiddenLayers[l][i].Bias);
}
}
}
double[] finalOutputs = new double[this.OutputNodes];
for (int i = 0; i < this.OutputNodes; i++)
{
finalOutputs[i] = this.OutputLayer[i].Value;
}
int maxIndex = 0;
double aux = 0.0;
for (int i = 0; i < this.OutputNodes; i++)
{
if (finalOutputs[i] > aux)
{
aux = finalOutputs[i];
maxIndex = i;
}
}
return(maxIndex == trainingExample.ResultIndex);
}
