Exemple #1
0
func TestChebyshev(t *testing.T) {
	var vectorX, vectorY *mat64.Dense
	chebyshev := NewChebyshev()

	Convey("Given two vectors", t, func() {
		vectorX = mat64.NewDense(4, 1, []float64{1, 2, 3, 4})
		vectorY = mat64.NewDense(4, 1, []float64{-5, -6, 7, 8})

		Convey("When calculating distance with two vectors", func() {
			result := chebyshev.Distance(vectorX, vectorY)

			Convey("The result should be 8", func() {
				So(result, ShouldEqual, 8)
			})
		})

		Convey("When calculating distance with row vectors", func() {
			vectorX.Copy(vectorX.T())
			vectorY.Copy(vectorY.T())
			result := chebyshev.Distance(vectorX, vectorY)

			Convey("The result should be 8", func() {
				So(result, ShouldEqual, 8)
			})
		})

		Convey("When calculating distance with different dimension matrices", func() {
			vectorX.Clone(vectorX.T())
			So(func() { chebyshev.Distance(vectorX, vectorY) }, ShouldPanic)
		})

	})
}
Exemple #2
0
func TestCranberrra(t *testing.T) {
	var vectorX, vectorY *mat64.Dense
	cranberra := NewCranberra()

	Convey("Given two vectors that are same", t, func() {
		vec := mat64.NewDense(7, 1, []float64{0, 1, -2, 3.4, 5, -6.7, 89})
		distance := cranberra.Distance(vec, vec)

		Convey("The result should be 0", func() {
			So(distance, ShouldEqual, 0)
		})
	})

	Convey("Given two vectors", t, func() {
		vectorX = mat64.NewDense(5, 1, []float64{1, 2, 3, 4, 9})
		vectorY = mat64.NewDense(5, 1, []float64{-5, -6, 7, 4, 3})

		Convey("When calculating distance with two vectors", func() {
			result := cranberra.Distance(vectorX, vectorY)

			Convey("The result should be 2.9", func() {
				So(result, ShouldEqual, 2.9)
			})
		})

		Convey("When calculating distance with row vectors", func() {
			vectorX.Copy(vectorX.T())
			vectorY.Copy(vectorY.T())
			result := cranberra.Distance(vectorX, vectorY)

			Convey("The result should be 2.9", func() {
				So(result, ShouldEqual, 2.9)
			})
		})

		Convey("When calculating distance with different dimension matrices", func() {
			vectorX.Clone(vectorX.T())
			So(func() { cranberra.Distance(vectorX, vectorY) }, ShouldPanic)
		})

	})
}
Exemple #3
0
func TestManhattan(t *testing.T) {
	var vectorX, vectorY *mat64.Dense
	manhattan := NewManhattan()

	Convey("Given two vectors that are same", t, func() {
		vec := mat64.NewDense(7, 1, []float64{0, 1, -2, 3.4, 5, -6.7, 89})
		distance := manhattan.Distance(vec, vec)

		Convey("The result should be 0", func() {
			So(distance, ShouldEqual, 0)
		})
	})

	Convey("Given two vectors", t, func() {
		vectorX = mat64.NewDense(3, 1, []float64{2, 2, 3})
		vectorY = mat64.NewDense(3, 1, []float64{1, 4, 5})

		Convey("When calculating distance with column vectors", func() {
			result := manhattan.Distance(vectorX, vectorY)

			Convey("The result should be 5", func() {
				So(result, ShouldEqual, 5)
			})
		})

		Convey("When calculating distance with row vectors", func() {
			vectorX.Copy(vectorX.T())
			vectorY.Copy(vectorY.T())
			result := manhattan.Distance(vectorX, vectorY)

			Convey("The result should be 5", func() {
				So(result, ShouldEqual, 5)
			})
		})

		Convey("When calculating distance with different dimension matrices", func() {
			vectorX.Clone(vectorX.T())
			So(func() { manhattan.Distance(vectorX, vectorY) }, ShouldPanic)
		})

	})
}
Exemple #4
0
// LinearSolve trains a Linear algorithm.
// Assumes inputs and outputs are already scaled
// If features is nil will call featurize
// Will return nil if regularizer is not a linear regularizer
// Is destructive if any of the weights are zero
// Losser is always the two-norm
// Does not set the value of the parameters (in case this is called in parallel with a different routine)
func LinearSolve(linearTrainable LinearTrainable, features *mat64.Dense, inputs, trueOutputs common.RowMatrix,
	weights []float64, regularizer regularize.Regularizer) (parameters []float64) {
	// TODO: Allow tikhonov regularization
	// TODO: Add test for weights
	// TODO: Need to do something about returning a []float64

	if !IsLinearSolveRegularizer(regularizer) {
		return nil
	}

	if features == nil {
		features = FeaturizeTrainable(linearTrainable, inputs, features)
	}

	_, nFeatures := features.Dims()

	var weightedFeatures, weightedOutput *mat64.Dense

	fmt.Println("In linear solve")

	if weights != nil {
		panic("Need functionality to be better. Either banded special case in matrix or do the mulitplication by hand")
		scaledWeight := make([]float64, len(weights))
		for i, weight := range weights {
			scaledWeight[i] = math.Sqrt(weight)
		}
		diagWeight := diagonal.NewDiagonal(len(scaledWeight), scaledWeight)

		nSamples, outputDim := trueOutputs.Dims()
		weightedOutput = mat64.NewDense(nSamples, outputDim, nil)
		weightedFeatures = mat64.NewDense(nSamples, nFeatures, nil)

		weightedOutput.Copy(trueOutputs)
		weightedFeatures.Copy(features)

		// TODO: Replace this with better than mat multiply
		weightedOutput.Mul(diagWeight, weightedOutput)
		weightedFeatures.Mul(diagWeight, weightedFeatures)
	}

	switch regularizer.(type) {
	case nil:
	case regularize.None:
	default:
		panic("Shouldn't be here. Must be error in IsLinearRegularizer")
	}

	if weights == nil {
		parameterMat, err := mat64.Solve(features, trueOutputs)
		if err != nil {
			panic(err)
		}
		return parameterMat.RawMatrix().Data

	}
	parameterMat, err := mat64.Solve(weightedFeatures, weightedOutput)
	if err != nil {
		panic(err)
	}

	return parameterMat.RawMatrix().Data
}