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Add euclidean distance test.

This commit is contained in:
Bert Chang 2014-05-02 23:49:06 +08:00
parent 921efaffc7
commit 4fc0ed0477
2 changed files with 27 additions and 9 deletions

View File

@ -23,7 +23,12 @@ func (self *Euclidean) InnerProduct(vectorX *mat.DenseMatrix, vectorY *mat.Dense
// We may need to create Metrics / Vector interface for this
func (self *Euclidean) Distance(vectorX *mat.DenseMatrix, vectorY *mat.DenseMatrix) (float64, error) {
difference, err := vectorY.MinusDense(vectorX)
if err != nil {
return 0, err
}
result := self.InnerProduct(difference, difference)
return math.Sqrt(result), err
return math.Sqrt(result), nil
}

View File

@ -7,27 +7,40 @@ import (
mat "github.com/skelterjohn/go.matrix"
)
func TestEuclideanInnerProduct(t *testing.T) {
func TestEuclidean(t *testing.T) {
euclidean := NewEuclidean()
Convey("Given two vectors", t, func() {
vectorX := mat.MakeDenseMatrix([]float64{1, 2, 3}, 3, 1)
vectorY := mat.MakeDenseMatrix([]float64{3, 4, 5}, 3, 1)
vectorY := mat.MakeDenseMatrix([]float64{2, 4, 5}, 3, 1)
Convey("When doing inner product", func() {
result := euclidean.InnerProduct(vectorX, vectorY)
Convey("The result should be 26", func() {
So(result, ShouldEqual, 26)
Convey("The result should be 25", func() {
So(result, ShouldEqual, 25)
})
Convey("When dimension not match", func() {
vectorZ := mat.MakeDenseMatrix([]float64{3, 4, 5}, 1, 3)
Convey("It should panic with Dimension mismatch", func() {
So(func() { euclidean.InnerProduct(vectorX, vectorZ) }, ShouldPanicWith, "Dimension mismatch")
})
})
})
Convey("When dimension not match", func() {
vectorY = mat.MakeDenseMatrix([]float64{3, 4, 5}, 1, 3)
Convey("When calculating distance", func() {
result, err := euclidean.Distance(vectorX, vectorY)
Convey("It should panic with Dimension mismatch", func() {
So(func() { euclidean.InnerProduct(vectorX, vectorY) }, ShouldPanicWith, "Dimension mismatch")
Convey("The err should be nil", func() {
So(err, ShouldBeNil)
})
Convey("The result should be 3", func() {
So(result, ShouldEqual, 3)
})
})