public static void DataTableToTensor(DataTable table, TensorOld result, params string[] columns)
{
for (int i = 0; i < table.Rows.Count; i++)
{
for (int j = 0; j < columns.Length; j++)
{
result[i, j] = double.Parse(table.Rows[i][columns[j]].ToString());
}
}
}
/// <summary>
/// 用于预测时的内存分配
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
public TensorOld PreparePredict(TensorOld input)
{
if (input.Rank != 2)
{
throw new TensorShapeException("input tensor must have Rank=2");
}
ForwardOutput = new TensorOld(input.shape[0], UnitCount);
return(ForwardOutput);
}
public void OptimizeTest()
{
var target = new TensorOld(new double[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 }, 3, 3);
var gradient = new TensorOld(new double[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 }, 3, 3);
var expected = new TensorOld(new double[] { 0.9, 1.8, 2.7, 3.6, 4.5, 5.4, 6.3, 7.2, 8.1 }, 3, 3);
var gd = new GradientDescent(0.1);
gd.Optimize(target, gradient);
Assert.Equal(expected, target);
}
public TensorOld Predict(TensorOld X)
{
CheckPredictShape(X);
for (int i = 0; i < PredictLayers.Count; i++)
{
X = PredictLayers[i].Forward(X);
}
return(X);
}
private void CheckTrainShape(TensorOld input, TensorOld y)
{
if (CheckShape(input.shape, trainInputShape) &&
CheckShape(y.shape, trainYShape))
{
return;
}
PrepareTrain(input, y);
}
public TensorOld Backward(TensorOld error)
{
var layers = TrainingLayers.Count - 1;
for (int i = layers; i > -1; i--)
{
error = TrainingLayers[i].Backward(error);
}
return(error);
}
public void ForwardBackwardTest()
{
var input = new TensorOld(new double[]
{
4, 6, 1, 4,
8, 4, 5, 1,
5, 3, 5, 7,
1, 7, 2, 8,
}, 1, 1, 4, 4);
var conv = new ConvLayer(4, 2, 1, 1);
conv.SetFilters(new TensorOld(new double[]
{
1, 1, 0, 0,
0, 0, 1, 1,
1, 0, 1, 0,
0, 1, 0, 1,
}, 4, 1, 2, 2));
var expected = new TensorOld(new double[]
{
0, 0, 0, 0, 0,
4, 10, 7, 5, 4,
8, 12, 9, 6, 1,
5, 8, 8, 12, 7,
1, 8, 9, 10, 8,
4, 10, 7, 5, 4,
8, 12, 9, 6, 1,
5, 8, 8, 12, 7,
1, 8, 9, 10, 8,
0, 0, 0, 0, 0,
0, 4, 6, 1, 4,
0, 12, 10, 6, 5,
0, 13, 7, 10, 8,
0, 6, 10, 7, 15,
0, 1, 7, 2, 8,
4, 6, 1, 4, 0,
12, 10, 6, 5, 0,
13, 7, 10, 8, 0,
6, 10, 7, 15, 0,
1, 7, 2, 8, 0,
}, 1, 4, 5, 5);
conv.PrepareTrain(input);
var acutal = conv.Forward(input);
Assert.Equal(acutal, expected);
var error = expected / 10;
var back = conv.Backward(error);
}
public MinMaxNorm(TensorOld tensor)
{
Min = tensor.Min();
Max = tensor.Max();
Denom = Max - Min;
if (Denom == 0)
{
throw new Exception("max=min");
}
}
/// <summary>
/// 反向传播或叫向前传播
/// </summary>
/// <param name="error">传回来的误差</param>
/// <returns>传到前面的误差</returns>
public override TensorOld Backward(TensorOld error)
{
ComputeDerivative();
//Parallel.For(0, sampleNumber, (Action<int>)(i =>
//{
// //这个方法直接将计算结果写入result，不需要开辟中间内存
// ErrorBP((Tensor)base.ForwardOutput, error, BackwardOutput, i);
//}));
ErrorBP(error);
return(BackwardOutput);
}
public override TensorOld Forward(TensorOld input)
{
Parallel.For(0, ForwardOutput.shape[0], sampleIndex =>
{
Parallel.For(0, ForwardOutput.shape[1], channel =>
{
PoolingChannel(input, sampleIndex, channel);
});
});
return(ForwardOutput);
}
public static TensorOld <TOut> DoScalarCellByCell <TOut, TIn1, TIn2>(this TensorOld <TIn1> t1, TIn2 val2, Func <TIn1, TIn2, TOut> operation)
{
TensorOld <TOut> result = new TensorOld <TOut>(t1.ShapeDimensions.ToArray());
for (int i = 0; i < t1.TheSpan.NumberSubArrays; i++)
{
result.TheSpan[i] = operation(t1.TheSpan[i], val2);
}
return(result);
}
public void SetFilters(TensorOld filters)
{
if (Filters == null)
{
foreach (var item in mirrorList)
{
item.Filters = filters;
}
}
TensorOld.CheckShape(filters, Filters);
Array.Copy(filters.values, 0, Filters.values, 0, Filters.ElementCount);
}
public void TransposeTest()
{
var a = new TensorOld(new double[, ] {
{ 1, 2, 3 }, { 4, 5, 6 }
});
var actual = a.Transpose();
var expected = new TensorOld(new double[, ] {
{ 1, 4 }, { 2, 5 }, { 3, 6 }
});
Assert.Equal(expected, actual);
}
public static void ApproximatelyEqual(TensorOld a, TensorOld b, double allowError = 0.00001)
{
Assert.True(TensorOld.CheckShapeBool(a, b));
var dataA = a.GetRawValues();
var dataB = b.GetRawValues();
for (int i = 0; i < a.ElementCount; i++)
{
Assert.True(Math.Abs(dataA[i] - dataB[i]) < allowError);
}
}
private void ComputeGradient(TensorOld error)
{
FiltersGradient.Clear();
Parallel.For(0, samples, sampleIndex =>
{
Parallel.For(0, FilterCount, filterIndex =>
{
ComputeGradient(error, sampleIndex, filterIndex);
});
});
}
private void ErrorBackward(TensorOld error)
{
BackwardOutput.Clear();
Parallel.For(0, samples, sampleIndex =>
{
Parallel.For(0, FilterCount, filterIndex =>
{
ErrorBackward(error, sampleIndex, filterIndex);
});
});
}
public void SetBias(TensorOld bias)
{
if (Bias == null)
{
foreach (var item in mirrorList)
{
item.Bias = bias;
}
}
TensorOld.CheckShape(Bias, bias);
Array.Copy(bias.GetRawValues(), 0, Bias.GetRawValues(), 0, Bias.ElementCount);
}
/// <summary>
/// Map解码
/// </summary>
/// <param name="t">要解码的数据</param>
/// <returns>解码结果</returns>
public override List <string> Decode(TensorOld t)
{
var result = new List <string>(t.ElementCount);
for (int i = 0; i < t.shape[0]; i++)
{
var index = Map2Index((int)t.GetRawValues()[i]);
result.Add(Categories[index]);
}
return(result);
}
public void PrepareTrain(TensorOld X, TensorOld y)
{
trainInputShape = X.shape;
trainYShape = y.shape;
for (int i = 0; i < TrainingLayers.Count; i++)
{
X = TrainingLayers[i].PrepareTrain(X);
}
LossFunction.PrepareTrain(X, y);
}
public void ZScoreTest()
{
var data = new TensorOld(new double[] { 1, 2, 3 });
var norm = new ZScoreNorm(data);
var test = new TensorOld(new double[] { 1.5, 2.5 });
var result = norm.Normalize(test);
Assert.Equal(2, norm.Mean);
Assert.Equal(Math.Sqrt(2d / 3d), norm.Delta);
Assert.True(result[0] < 0);
Assert.True(result[1] > 0);
}
/// <summary>
/// 手动设置权重
/// </summary>
/// <param name="weights"></param>
public void SetWeights(TensorOld weights)
{
if (Weights == null)
{
foreach (var item in mirrorList)
{
item.Weights = weights;
}
}
TensorOld.CheckShape(weights, Weights);
Array.Copy(weights.GetRawValues(), 0, Weights.GetRawValues(), 0, Weights.ElementCount);
}
/// <summary>
/// 正向传播或叫向后传播
/// </summary>
/// <param name="input">输入的数值</param>
/// <returns>输出的数值</returns>
public override TensorOld Forward(TensorOld input)
{
int startIndex;
for (int i = 0; i < sampleNumber; i++)
{
startIndex = categoryNumber * i;
Array.Copy(input.values, startIndex, sampleBuff, 0, categoryNumber);
Functions.Softmax(sampleBuff, sampleBuff);
Array.Copy(sampleBuff, 0, ForwardOutput.values, startIndex, categoryNumber);
}
return(ForwardOutput);
}
public void Play()
{
var data = DataEmulator.Instance.RandomArray(100000);
var tensor = new TensorOld(data, 500, 200);
var full = new FullLayer(100);
full.PrepareTrain(tensor);
var start1 = DateTime.Now;
var output = full.Forward(tensor);
var ts1 = DateTime.Now - start1;
Console.WriteLine($"Forward Time:{ts1.TotalMilliseconds}");
}
public override TensorOld PreparePredict(TensorOld input)
{
if (input.Rank != 2)
{
throw new TensorShapeException("input.Rank must be 2");
}
ForwardOutput = input.GetSameShape();
sampleNumber = input.Shape[0];
categoryNumber = input.Shape[1];
sampleBuff = new double[categoryNumber];
return(ForwardOutput);
}
public TensorOld Forward(TensorOld input)
{
SetPaddingInput(input);
Parallel.For(0, samples, sampleIndex =>
{
Parallel.For(0, FilterCount, filterIndex =>
{
Forward(input, sampleIndex, filterIndex);
});
});
return(ForwardOutput);
}
public static TensorOld <TOut> Cast <TIn, TOut>(this TensorOld <TIn> t, Func <TIn, TOut> converter = null)
{
if (converter == null)
{
converter = NumericUtils.GetNumericConverter <TIn, TOut>();
}
TensorOld <TOut> result = new TensorOld <TOut>(t.ShapeDimensions.ToArray());
result.SetSpan(t.TheSpan.Select(item => converter(item)));
return(result);
}
public override TensorOld Backward(TensorOld error)
{
BackwardOutput.Clear();
Parallel.For(0, ForwardOutput.shape[0], sampleIndex =>
{
Parallel.For(0, ForwardOutput.shape[1], channel =>
{
ErrorBP(error, sampleIndex, channel);
});
});
return(BackwardOutput);
}
public static TensorOld <TOut> DoCellByCell <TOut, TIn1, TIn2>(this TensorOld <TIn1> t1, TensorOld <TIn2> t2, Func <TIn1, TIn2, TOut> operation)
{
t1.CheckEqualDimensions(t2);
TensorOld <TOut> result = new TensorOld <TOut>(t1.ShapeDimensions.ToArray());
for (int i = 0; i < t1.TheSpan.NumberSubArrays; i++)
{
result.TheSpan[i] = operation(t1.TheSpan[i], t2.TheSpan[i]);
}
return(result);
}
public void ApplyTest()
{
var t = TensorOld.Rand(20, 30);
var n = TensorOld.Apply(t, a => a * a);
for (int i = 0; i < 20; i++)
{
for (int j = 0; j < 30; j++)
{
Assert.Equal(t[i, j] * t[i, j], n[i, j]);
}
}
}
public void MeanSquareErrorTest()
{
var y = new TensorOld(new double[] { 1, 3, 2, 4, 5, 6 });
var yHat = new TensorOld(new double[] { 1.5, 2.6, 2.1, 3.9, 5.3, 6.7 });
var loss = Functions.MeanSquareError(y, yHat);
var gradient = Derivatives.MeanSquareError(y, yHat);
var delta = 0.00001;
yHat[0] += delta;
var expected = (Functions.MeanSquareError(y, yHat) - loss) / delta;
MyAssert.ApproximatelyEqual(expected, gradient[0]);
}