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33 lines
619 B
Go
33 lines
619 B
Go
package pairwise
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import (
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"math"
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"github.com/gonum/matrix/mat64"
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)
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type Manhattan struct{}
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func NewManhattan() *Manhattan {
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return &Manhattan{}
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}
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// Distance computes the Manhattan distance, also known as L1 distance.
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// == the sum of the absolute values of elements.
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func (m *Manhattan) Distance(vectorX *mat64.Dense, vectorY *mat64.Dense) float64 {
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r1, c1 := vectorX.Dims()
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r2, c2 := vectorY.Dims()
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if r1 != r2 || c1 != c2 {
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panic(mat64.ErrShape)
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}
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result := .0
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for i := 0; i < r1; i++ {
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for j := 0; j < c1; j++ {
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result += math.Abs(vectorX.At(i, j) - vectorY.At(i, j))
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}
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}
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return result
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}
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