Adds matrix sub package & adds polynomial regression series (#36)
* updates * updates * tests. * test coverage * fixing test * stride not rows + cols * lu decomp implementation. * poly regression! * poly regression works. * typo.
This commit is contained in:
Will Charczuk
GitHub
parent
b3dc3fef3c
commit
a211e88530
10 changed files with 1292 additions and 9 deletions
41
_examples/poly_regression/main.go
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41
_examples/poly_regression/main.go
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@ -0,0 +1,41 @@
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package main
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import (
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"net/http"
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"github.com/wcharczuk/go-chart"
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)
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func drawChart(res http.ResponseWriter, req *http.Request) {
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/*
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In this example we add a new type of series, a `PolynomialRegressionSeries` that takes another series as a required argument.
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InnerSeries only needs to implement `ValueProvider`, so really you could chain `PolynomialRegressionSeries` together if you wanted.
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*/
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mainSeries := chart.ContinuousSeries{
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Name: "A test series",
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XValues: chart.Sequence.Float64(1.0, 100.0), //generates a []float64 from 1.0 to 100.0 in 1.0 step increments, or 100 elements.
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YValues: chart.Sequence.Random(100, 100), //generates a []float64 randomly from 0 to 100 with 100 elements.
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}
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polyRegSeries := &chart.PolynomialRegressionSeries{
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Degree: 3,
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InnerSeries: mainSeries,
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}
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graph := chart.Chart{
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Series: []chart.Series{
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mainSeries,
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polyRegSeries,
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},
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}
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res.Header().Set("Content-Type", "image/png")
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graph.Render(chart.PNG, res)
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}
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func main() {
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http.HandleFunc("/", drawChart)
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http.ListenAndServe(":8080", nil)
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}
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@ -9,7 +9,7 @@ type LinearRegressionSeries struct {
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Style Style
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YAxis YAxisType
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Window int
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Limit int
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Offset int
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InnerSeries ValueProvider
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@ -36,18 +36,18 @@ func (lrs LinearRegressionSeries) GetYAxis() YAxisType {
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// Len returns the number of elements in the series.
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func (lrs LinearRegressionSeries) Len() int {
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return Math.MinInt(lrs.GetWindow(), lrs.InnerSeries.Len()-lrs.GetOffset())
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return Math.MinInt(lrs.GetLimit(), lrs.InnerSeries.Len()-lrs.GetOffset())
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}
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// GetWindow returns the window size.
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func (lrs LinearRegressionSeries) GetWindow() int {
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if lrs.Window == 0 {
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// GetLimit returns the window size.
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func (lrs LinearRegressionSeries) GetLimit() int {
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if lrs.Limit == 0 {
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return lrs.InnerSeries.Len()
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}
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return lrs.Window
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return lrs.Limit
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}
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// GetEndIndex returns the effective window end.
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// GetEndIndex returns the effective limit end.
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func (lrs LinearRegressionSeries) GetEndIndex() int {
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offset := lrs.GetOffset() + lrs.Len()
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innerSeriesLastIndex := lrs.InnerSeries.Len() - 1
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@ -105,7 +105,6 @@ func (lrs *LinearRegressionSeries) computeCoefficients() {
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xvalues := NewRingBufferWithCapacity(lrs.Len())
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for index := startIndex; index < endIndex; index++ {
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x, _ := lrs.InnerSeries.GetValue(index)
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xvalues.Enqueue(x)
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}
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@ -62,7 +62,7 @@ func TestLinearRegressionSeriesWindowAndOffset(t *testing.T) {
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linRegSeries := &LinearRegressionSeries{
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InnerSeries: mainSeries,
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Offset: 10,
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Window: 10,
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Limit: 10,
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}
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assert.Equal(10, linRegSeries.Len())
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592
matrix/matrix.go
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592
matrix/matrix.go
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@ -0,0 +1,592 @@
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package matrix
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import (
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"bytes"
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"errors"
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"fmt"
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"math"
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)
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const (
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// DefaultEpsilon represents the minimum precision for matrix math operations.
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DefaultEpsilon = 0.000001
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)
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var (
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// ErrDimensionMismatch is a typical error.
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ErrDimensionMismatch = errors.New("dimension mismatch")
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// ErrSingularValue is a typical error.
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ErrSingularValue = errors.New("singular value")
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)
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// New returns a new matrix.
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func New(rows, cols int, values ...float64) *Matrix {
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if len(values) == 0 {
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return &Matrix{
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stride: cols,
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epsilon: DefaultEpsilon,
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elements: make([]float64, rows*cols),
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}
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}
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elems := make([]float64, rows*cols)
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copy(elems, values)
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return &Matrix{
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stride: cols,
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epsilon: DefaultEpsilon,
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elements: elems,
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}
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}
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// Identity returns the identity matrix of a given order.
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func Identity(order int) *Matrix {
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m := New(order, order)
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for i := 0; i < order; i++ {
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m.Set(i, i, 1)
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}
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return m
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}
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// Zero returns a matrix of a given size zeroed.
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func Zero(rows, cols int) *Matrix {
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return New(rows, cols)
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}
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// Ones returns an matrix of ones.
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func Ones(rows, cols int) *Matrix {
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ones := make([]float64, rows*cols)
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for i := 0; i < (rows * cols); i++ {
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ones[i] = 1
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}
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return &Matrix{
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stride: cols,
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epsilon: DefaultEpsilon,
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elements: ones,
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}
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}
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// Eye returns the eye matrix.
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func Eye(n int) *Matrix {
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m := Zero(n, n)
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for i := 0; i < len(m.elements); i += n + 1 {
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m.elements[i] = 1
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}
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return m
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}
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// NewFromArrays creates a matrix from a jagged array set.
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func NewFromArrays(a [][]float64) *Matrix {
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rows := len(a)
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if rows == 0 {
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return nil
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}
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cols := len(a[0])
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m := New(rows, cols)
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for row := 0; row < rows; row++ {
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for col := 0; col < cols; col++ {
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m.Set(row, col, a[row][col])
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}
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}
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return m
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}
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// Matrix represents a 2d dense array of floats.
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type Matrix struct {
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epsilon float64
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elements []float64
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stride int
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}
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// String returns a string representation of the matrix.
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func (m *Matrix) String() string {
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buffer := bytes.NewBuffer(nil)
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rows, cols := m.Size()
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for row := 0; row < rows; row++ {
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for col := 0; col < cols; col++ {
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buffer.WriteString(f64s(m.Get(row, col)))
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buffer.WriteRune(' ')
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}
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buffer.WriteRune('\n')
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}
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return buffer.String()
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}
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// Epsilon returns the maximum precision for math operations.
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func (m *Matrix) Epsilon() float64 {
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return m.epsilon
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}
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// WithEpsilon sets the epsilon on the matrix and returns a reference to the matrix.
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func (m *Matrix) WithEpsilon(epsilon float64) *Matrix {
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m.epsilon = epsilon
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return m
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}
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// Each applies the action to each element of the matrix in
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// rows => cols order.
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func (m *Matrix) Each(action func(row, cow int, value float64)) {
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rows, cols := m.Size()
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for row := 0; row < rows; row++ {
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for col := 0; col < cols; col++ {
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action(row, col, m.Get(row, col))
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}
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}
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}
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// Round rounds all the values in a matrix to it epsilon,
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// returning a reference to the original
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func (m *Matrix) Round() *Matrix {
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rows, cols := m.Size()
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for row := 0; row < rows; row++ {
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for col := 0; col < cols; col++ {
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m.Set(row, col, roundToEpsilon(m.Get(row, col), m.epsilon))
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}
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}
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return m
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}
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// Arrays returns the matrix as a two dimensional jagged array.
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func (m *Matrix) Arrays() [][]float64 {
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rows, cols := m.Size()
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a := make([][]float64, rows)
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for row := 0; row < rows; row++ {
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a[row] = make([]float64, cols)
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for col := 0; col < cols; col++ {
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a[row][col] = m.Get(row, col)
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}
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}
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return a
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}
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// Size returns the dimensions of the matrix.
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func (m *Matrix) Size() (rows, cols int) {
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rows = len(m.elements) / m.stride
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cols = m.stride
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return
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}
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// IsSquare returns if the row count is equal to the column count.
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func (m *Matrix) IsSquare() bool {
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return m.stride == (len(m.elements) / m.stride)
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}
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// IsSymmetric returns if the matrix is symmetric about its diagonal.
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func (m *Matrix) IsSymmetric() bool {
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rows, cols := m.Size()
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if rows != cols {
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return false
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}
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for i := 0; i < rows; i++ {
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for j := 0; j < i; j++ {
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if m.Get(i, j) != m.Get(j, i) {
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return false
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}
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}
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}
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return true
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}
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// Get returns the element at the given row, col.
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func (m *Matrix) Get(row, col int) float64 {
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index := (m.stride * row) + col
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return m.elements[index]
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}
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// Set sets a value.
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func (m *Matrix) Set(row, col int, val float64) {
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index := (m.stride * row) + col
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m.elements[index] = val
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}
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// Col returns a column of the matrix as a vector.
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func (m *Matrix) Col(col int) Vector {
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rows, _ := m.Size()
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values := make([]float64, rows)
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for row := 0; row < rows; row++ {
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values[row] = m.Get(row, col)
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}
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return Vector(values)
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}
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// Row returns a row of the matrix as a vector.
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func (m *Matrix) Row(row int) Vector {
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_, cols := m.Size()
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values := make([]float64, cols)
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for col := 0; col < cols; col++ {
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values[col] = m.Get(row, col)
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}
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return Vector(values)
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}
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// SubMatrix returns a sub matrix from a given outer matrix.
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func (m *Matrix) SubMatrix(i, j, rows, cols int) *Matrix {
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return &Matrix{
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elements: m.elements[i*m.stride+j : i*m.stride+j+(rows-1)*m.stride+cols],
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stride: m.stride,
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epsilon: m.epsilon,
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}
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}
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// ScaleRow applies a scale to an entire row.
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func (m *Matrix) ScaleRow(row int, scale float64) {
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startIndex := row * m.stride
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for i := startIndex; i < m.stride; i++ {
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m.elements[i] = m.elements[i] * scale
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}
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}
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func (m *Matrix) scaleAddRow(rd int, rs int, f float64) {
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indexd := rd * m.stride
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indexs := rs * m.stride
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for col := 0; col < m.stride; col++ {
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m.elements[indexd] += f * m.elements[indexs]
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indexd++
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indexs++
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}
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}
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// SwapRows swaps a row in the matrix in place.
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func (m *Matrix) SwapRows(i, j int) {
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var vi, vj float64
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for col := 0; col < m.stride; col++ {
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vi = m.Get(i, col)
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vj = m.Get(j, col)
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m.Set(i, col, vj)
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m.Set(j, col, vi)
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}
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}
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// Augment concatenates two matrices about the horizontal.
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func (m *Matrix) Augment(m2 *Matrix) (*Matrix, error) {
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mr, mc := m.Size()
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m2r, m2c := m2.Size()
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if mr != m2r {
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return nil, ErrDimensionMismatch
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}
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m3 := Zero(mr, mc+m2c)
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for row := 0; row < mr; row++ {
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for col := 0; col < mc; col++ {
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m3.Set(row, col, m.Get(row, col))
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}
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for col := 0; col < m2c; col++ {
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m3.Set(row, mc+col, m2.Get(row, col))
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}
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}
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return m3, nil
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}
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// Copy returns a duplicate of a given matrix.
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func (m *Matrix) Copy() *Matrix {
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m2 := &Matrix{stride: m.stride, epsilon: m.epsilon, elements: make([]float64, len(m.elements))}
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copy(m2.elements, m.elements)
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return m2
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}
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// DiagonalVector returns a vector from the diagonal of a matrix.
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func (m *Matrix) DiagonalVector() Vector {
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rows, cols := m.Size()
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rank := minInt(rows, cols)
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values := make([]float64, rank)
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for index := 0; index < rank; index++ {
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values[index] = m.Get(index, index)
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}
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return Vector(values)
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}
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// Diagonal returns a matrix from the diagonal of a matrix.
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func (m *Matrix) Diagonal() *Matrix {
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rows, cols := m.Size()
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rank := minInt(rows, cols)
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m2 := New(rank, rank)
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for index := 0; index < rank; index++ {
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m2.Set(index, index, m.Get(index, index))
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}
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return m2
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}
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// Equals returns if a matrix equals another matrix.
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func (m *Matrix) Equals(other *Matrix) bool {
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if other == nil && m != nil {
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return false
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} else if other == nil {
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return true
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}
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if m.stride != other.stride {
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return false
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}
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msize := len(m.elements)
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m2size := len(other.elements)
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if msize != m2size {
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return false
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}
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for i := 0; i < msize; i++ {
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if m.elements[i] != other.elements[i] {
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return false
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}
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}
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return true
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}
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// L returns the matrix with zeros below the diagonal.
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func (m *Matrix) L() *Matrix {
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rows, cols := m.Size()
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m2 := New(rows, cols)
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for row := 0; row < rows; row++ {
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for col := row; col < cols; col++ {
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m2.Set(row, col, m.Get(row, col))
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}
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}
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return m2
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}
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// U returns the matrix with zeros above the diagonal.
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// Does not include the diagonal.
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func (m *Matrix) U() *Matrix {
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rows, cols := m.Size()
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m2 := New(rows, cols)
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for row := 0; row < rows; row++ {
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for col := 0; col < row && col < cols; col++ {
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m2.Set(row, col, m.Get(row, col))
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}
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}
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return m2
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}
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// math operations
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// Multiply multiplies two matrices.
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func (m *Matrix) Multiply(m2 *Matrix) (m3 *Matrix, err error) {
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if m.stride*m2.stride != len(m2.elements) {
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return nil, ErrDimensionMismatch
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}
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m3 = &Matrix{epsilon: m.epsilon, stride: m2.stride, elements: make([]float64, (len(m.elements)/m.stride)*m2.stride)}
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for m1c0, m3x := 0, 0; m1c0 < len(m.elements); m1c0 += m.stride {
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for m2r0 := 0; m2r0 < m2.stride; m2r0++ {
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for m1x, m2x := m1c0, m2r0; m2x < len(m2.elements); m2x += m2.stride {
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m3.elements[m3x] += m.elements[m1x] * m2.elements[m2x]
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m1x++
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}
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m3x++
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}
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}
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return
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}
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// Pivotize does something i'm not sure what.
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func (m *Matrix) Pivotize() *Matrix {
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pv := make([]int, m.stride)
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for i := range pv {
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pv[i] = i
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}
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for j, dx := 0, 0; j < m.stride; j++ {
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row := j
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max := m.elements[dx]
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for i, ixcj := j, dx; i < m.stride; i++ {
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if m.elements[ixcj] > max {
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max = m.elements[ixcj]
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row = i
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}
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ixcj += m.stride
|
||||
}
|
||||
if j != row {
|
||||
pv[row], pv[j] = pv[j], pv[row]
|
||||
}
|
||||
dx += m.stride + 1
|
||||
}
|
||||
p := Zero(m.stride, m.stride)
|
||||
for r, c := range pv {
|
||||
p.elements[r*m.stride+c] = 1
|
||||
}
|
||||
return p
|
||||
}
|
||||
|
||||
// Times returns the product of a matrix and another.
|
||||
func (m *Matrix) Times(m2 *Matrix) (*Matrix, error) {
|
||||
mr, mc := m.Size()
|
||||
m2r, m2c := m2.Size()
|
||||
|
||||
if mc != m2r {
|
||||
return nil, fmt.Errorf("cannot multiply (%dx%d) and (%dx%d)", mr, mc, m2r, m2c)
|
||||
//return nil, ErrDimensionMismatch
|
||||
}
|
||||
|
||||
c := Zero(mr, m2c)
|
||||
|
||||
for i := 0; i < mr; i++ {
|
||||
sums := c.elements[i*c.stride : (i+1)*c.stride]
|
||||
for k, a := range m.elements[i*m.stride : i*m.stride+m.stride] {
|
||||
for j, b := range m2.elements[k*m2.stride : k*m2.stride+m2.stride] {
|
||||
sums[j] += a * b
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return c, nil
|
||||
}
|
||||
|
||||
// Decompositions
|
||||
|
||||
// LU performs the LU decomposition.
|
||||
func (m *Matrix) LU() (l, u, p *Matrix) {
|
||||
l = Zero(m.stride, m.stride)
|
||||
u = Zero(m.stride, m.stride)
|
||||
p = m.Pivotize()
|
||||
m, _ = p.Multiply(m)
|
||||
for j, jxc0 := 0, 0; j < m.stride; j++ {
|
||||
l.elements[jxc0+j] = 1
|
||||
for i, ixc0 := 0, 0; ixc0 <= jxc0; i++ {
|
||||
sum := 0.
|
||||
for k, kxcj := 0, j; k < i; k++ {
|
||||
sum += u.elements[kxcj] * l.elements[ixc0+k]
|
||||
kxcj += m.stride
|
||||
}
|
||||
u.elements[ixc0+j] = m.elements[ixc0+j] - sum
|
||||
ixc0 += m.stride
|
||||
}
|
||||
for ixc0 := jxc0; ixc0 < len(m.elements); ixc0 += m.stride {
|
||||
sum := 0.
|
||||
for k, kxcj := 0, j; k < j; k++ {
|
||||
sum += u.elements[kxcj] * l.elements[ixc0+k]
|
||||
kxcj += m.stride
|
||||
}
|
||||
l.elements[ixc0+j] = (m.elements[ixc0+j] - sum) / u.elements[jxc0+j]
|
||||
}
|
||||
jxc0 += m.stride
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// QR performs the qr decomposition.
|
||||
func (m *Matrix) QR() (q, r *Matrix) {
|
||||
defer func() {
|
||||
q = q.Round()
|
||||
r = r.Round()
|
||||
}()
|
||||
|
||||
rows, cols := m.Size()
|
||||
qr := m.Copy()
|
||||
q = New(rows, cols)
|
||||
r = New(rows, cols)
|
||||
|
||||
var i, j, k int
|
||||
var norm, s float64
|
||||
|
||||
for k = 0; k < cols; k++ {
|
||||
norm = 0
|
||||
for i = k; i < rows; i++ {
|
||||
norm = math.Hypot(norm, qr.Get(i, k))
|
||||
}
|
||||
|
||||
if norm != 0 {
|
||||
if qr.Get(k, k) < 0 {
|
||||
norm = -norm
|
||||
}
|
||||
|
||||
for i = k; i < rows; i++ {
|
||||
qr.Set(i, k, qr.Get(i, k)/norm)
|
||||
}
|
||||
qr.Set(k, k, qr.Get(k, k)+1.0)
|
||||
|
||||
for j = k + 1; j < cols; j++ {
|
||||
s = 0
|
||||
for i = k; i < rows; i++ {
|
||||
s += qr.Get(i, k) * qr.Get(i, j)
|
||||
}
|
||||
s = -s / qr.Get(k, k)
|
||||
for i = k; i < rows; i++ {
|
||||
qr.Set(i, j, qr.Get(i, j)+s*qr.Get(i, k))
|
||||
|
||||
if i < j {
|
||||
r.Set(i, j, qr.Get(i, j))
|
||||
}
|
||||
}
|
||||
|
||||
}
|
||||
}
|
||||
|
||||
r.Set(k, k, -norm)
|
||||
|
||||
}
|
||||
|
||||
//Q Matrix:
|
||||
i, j, k = 0, 0, 0
|
||||
|
||||
for k = cols - 1; k >= 0; k-- {
|
||||
q.Set(k, k, 1.0)
|
||||
for j = k; j < cols; j++ {
|
||||
if qr.Get(k, k) != 0 {
|
||||
s = 0
|
||||
for i = k; i < rows; i++ {
|
||||
s += qr.Get(i, k) * q.Get(i, j)
|
||||
}
|
||||
s = -s / qr.Get(k, k)
|
||||
for i = k; i < rows; i++ {
|
||||
q.Set(i, j, q.Get(i, j)+s*qr.Get(i, k))
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return
|
||||
}
|
||||
|
||||
// Transpose flips a matrix about its diagonal, returning a new copy.
|
||||
func (m *Matrix) Transpose() *Matrix {
|
||||
rows, cols := m.Size()
|
||||
m2 := Zero(cols, rows)
|
||||
for i := 0; i < rows; i++ {
|
||||
for j := 0; j < cols; j++ {
|
||||
m2.Set(j, i, m.Get(i, j))
|
||||
}
|
||||
}
|
||||
return m2
|
||||
}
|
||||
|
||||
// Inverse returns a matrix such that M*I==1.
|
||||
func (m *Matrix) Inverse() (*Matrix, error) {
|
||||
if !m.IsSymmetric() {
|
||||
return nil, ErrDimensionMismatch
|
||||
}
|
||||
|
||||
rows, cols := m.Size()
|
||||
|
||||
aug, _ := m.Augment(Eye(rows))
|
||||
for i := 0; i < rows; i++ {
|
||||
j := i
|
||||
for k := i; k < rows; k++ {
|
||||
if math.Abs(aug.Get(k, i)) > math.Abs(aug.Get(j, i)) {
|
||||
j = k
|
||||
}
|
||||
}
|
||||
if j != i {
|
||||
aug.SwapRows(i, j)
|
||||
}
|
||||
if aug.Get(i, i) == 0 {
|
||||
return nil, ErrSingularValue
|
||||
}
|
||||
aug.ScaleRow(i, 1.0/aug.Get(i, i))
|
||||
for k := 0; k < rows; k++ {
|
||||
if k == i {
|
||||
continue
|
||||
}
|
||||
aug.scaleAddRow(k, i, -aug.Get(k, i))
|
||||
}
|
||||
}
|
||||
return aug.SubMatrix(0, cols, rows, cols), nil
|
||||
}
|
||||
396
matrix/matrix_test.go
Normal file
396
matrix/matrix_test.go
Normal file
|
|
@ -0,0 +1,396 @@
|
|||
package matrix
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
assert "github.com/blendlabs/go-assert"
|
||||
)
|
||||
|
||||
func TestNew(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := New(10, 5)
|
||||
rows, cols := m.Size()
|
||||
assert.Equal(10, rows)
|
||||
assert.Equal(5, cols)
|
||||
assert.Zero(m.Get(0, 0))
|
||||
assert.Zero(m.Get(9, 4))
|
||||
}
|
||||
|
||||
func TestNewWithValues(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := New(5, 2, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
|
||||
rows, cols := m.Size()
|
||||
assert.Equal(5, rows)
|
||||
assert.Equal(2, cols)
|
||||
assert.Equal(1, m.Get(0, 0))
|
||||
assert.Equal(10, m.Get(4, 1))
|
||||
}
|
||||
|
||||
func TestIdentitiy(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
id := Identity(5)
|
||||
rows, cols := id.Size()
|
||||
assert.Equal(5, rows)
|
||||
assert.Equal(5, cols)
|
||||
assert.Equal(1, id.Get(0, 0))
|
||||
assert.Equal(1, id.Get(1, 1))
|
||||
assert.Equal(1, id.Get(2, 2))
|
||||
assert.Equal(1, id.Get(3, 3))
|
||||
assert.Equal(1, id.Get(4, 4))
|
||||
assert.Equal(0, id.Get(0, 1))
|
||||
assert.Equal(0, id.Get(1, 0))
|
||||
assert.Equal(0, id.Get(4, 0))
|
||||
assert.Equal(0, id.Get(0, 4))
|
||||
}
|
||||
|
||||
func TestNewFromArrays(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3, 4},
|
||||
{5, 6, 7, 8},
|
||||
})
|
||||
assert.NotNil(m)
|
||||
|
||||
rows, cols := m.Size()
|
||||
assert.Equal(2, rows)
|
||||
assert.Equal(4, cols)
|
||||
}
|
||||
|
||||
func TestOnes(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
ones := Ones(5, 10)
|
||||
rows, cols := ones.Size()
|
||||
assert.Equal(5, rows)
|
||||
assert.Equal(10, cols)
|
||||
|
||||
for row := 0; row < rows; row++ {
|
||||
for col := 0; col < cols; col++ {
|
||||
assert.Equal(1, ones.Get(row, col))
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestMatrixEpsilon(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
ones := Ones(2, 2)
|
||||
ones = ones.WithEpsilon(0.001)
|
||||
assert.Equal(0.001, ones.Epsilon())
|
||||
}
|
||||
|
||||
func TestMatrixArrays(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
})
|
||||
|
||||
assert.NotNil(m)
|
||||
|
||||
arrays := m.Arrays()
|
||||
|
||||
assert.Equal(arrays, [][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
})
|
||||
}
|
||||
|
||||
func TestMatrixIsSquare(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
assert.False(NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
}).IsSquare())
|
||||
|
||||
assert.False(NewFromArrays([][]float64{
|
||||
{1, 2},
|
||||
{3, 4},
|
||||
{5, 6},
|
||||
}).IsSquare())
|
||||
|
||||
assert.True(NewFromArrays([][]float64{
|
||||
{1, 2},
|
||||
{3, 4},
|
||||
}).IsSquare())
|
||||
}
|
||||
|
||||
func TestMatrixIsSymmetric(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
assert.False(NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{2, 1, 2},
|
||||
}).IsSymmetric())
|
||||
|
||||
assert.False(NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
}).IsSymmetric())
|
||||
|
||||
assert.True(NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{2, 1, 2},
|
||||
{3, 2, 1},
|
||||
}).IsSymmetric())
|
||||
|
||||
}
|
||||
|
||||
func TestMatrixGet(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
assert.Equal(1, m.Get(0, 0))
|
||||
assert.Equal(2, m.Get(0, 1))
|
||||
assert.Equal(3, m.Get(0, 2))
|
||||
assert.Equal(4, m.Get(1, 0))
|
||||
assert.Equal(5, m.Get(1, 1))
|
||||
assert.Equal(6, m.Get(1, 2))
|
||||
assert.Equal(7, m.Get(2, 0))
|
||||
assert.Equal(8, m.Get(2, 1))
|
||||
assert.Equal(9, m.Get(2, 2))
|
||||
}
|
||||
|
||||
func TestMatrixSet(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
m.Set(1, 1, 99)
|
||||
assert.Equal(99, m.Get(1, 1))
|
||||
}
|
||||
|
||||
func TestMatrixCol(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
assert.Equal([]float64{1, 4, 7}, m.Col(0))
|
||||
assert.Equal([]float64{2, 5, 8}, m.Col(1))
|
||||
assert.Equal([]float64{3, 6, 9}, m.Col(2))
|
||||
}
|
||||
|
||||
func TestMatrixRow(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
assert.Equal([]float64{1, 2, 3}, m.Row(0))
|
||||
assert.Equal([]float64{4, 5, 6}, m.Row(1))
|
||||
assert.Equal([]float64{7, 8, 9}, m.Row(2))
|
||||
}
|
||||
|
||||
func TestMatrixSwapRows(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
m.SwapRows(0, 1)
|
||||
|
||||
assert.Equal([]float64{4, 5, 6}, m.Row(0))
|
||||
assert.Equal([]float64{1, 2, 3}, m.Row(1))
|
||||
assert.Equal([]float64{7, 8, 9}, m.Row(2))
|
||||
}
|
||||
|
||||
func TestMatrixCopy(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
m2 := m.Copy()
|
||||
assert.False(m == m2)
|
||||
assert.True(m.Equals(m2))
|
||||
}
|
||||
|
||||
func TestMatrixDiagonalVector(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 4, 7},
|
||||
{4, 2, 8},
|
||||
{7, 8, 3},
|
||||
})
|
||||
|
||||
diag := m.DiagonalVector()
|
||||
assert.Equal([]float64{1, 2, 3}, diag)
|
||||
}
|
||||
|
||||
func TestMatrixDiagonalVectorLandscape(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 4, 7, 99},
|
||||
{4, 2, 8, 99},
|
||||
})
|
||||
|
||||
diag := m.DiagonalVector()
|
||||
assert.Equal([]float64{1, 2}, diag)
|
||||
}
|
||||
|
||||
func TestMatrixDiagonalVectorPortrait(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 4},
|
||||
{4, 2},
|
||||
{99, 99},
|
||||
})
|
||||
|
||||
diag := m.DiagonalVector()
|
||||
assert.Equal([]float64{1, 2}, diag)
|
||||
}
|
||||
|
||||
func TestMatrixDiagonal(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 4, 7},
|
||||
{4, 2, 8},
|
||||
{7, 8, 3},
|
||||
})
|
||||
|
||||
m2 := NewFromArrays([][]float64{
|
||||
{1, 0, 0},
|
||||
{0, 2, 0},
|
||||
{0, 0, 3},
|
||||
})
|
||||
|
||||
assert.True(m.Diagonal().Equals(m2))
|
||||
}
|
||||
|
||||
func TestMatrixEquals(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 4, 7},
|
||||
{4, 2, 8},
|
||||
{7, 8, 3},
|
||||
})
|
||||
|
||||
assert.False(m.Equals(nil))
|
||||
var nilMatrix *Matrix
|
||||
assert.True(nilMatrix.Equals(nil))
|
||||
assert.False(m.Equals(New(1, 1)))
|
||||
assert.False(m.Equals(New(3, 3)))
|
||||
assert.True(m.Equals(New(3, 3, 1, 4, 7, 4, 2, 8, 7, 8, 3)))
|
||||
}
|
||||
|
||||
func TestMatrixL(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
l := m.L()
|
||||
assert.True(l.Equals(New(3, 3, 1, 2, 3, 0, 5, 6, 0, 0, 9)))
|
||||
}
|
||||
|
||||
func TestMatrixU(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
u := m.U()
|
||||
assert.True(u.Equals(New(3, 3, 0, 0, 0, 4, 0, 0, 7, 8, 0)))
|
||||
}
|
||||
|
||||
func TestMatrixString(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
})
|
||||
|
||||
assert.Equal("1 2 3 \n4 5 6 \n7 8 9 \n", m.String())
|
||||
}
|
||||
|
||||
func TestMatrixLU(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 3, 5},
|
||||
{2, 4, 7},
|
||||
{1, 1, 0},
|
||||
})
|
||||
|
||||
l, u, p := m.LU()
|
||||
assert.NotNil(l)
|
||||
assert.NotNil(u)
|
||||
assert.NotNil(p)
|
||||
}
|
||||
|
||||
func TestMatrixQR(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{12, -51, 4},
|
||||
{6, 167, -68},
|
||||
{-4, 24, -41},
|
||||
})
|
||||
|
||||
q, r := m.QR()
|
||||
assert.NotNil(q)
|
||||
assert.NotNil(r)
|
||||
}
|
||||
|
||||
func TestMatrixTranspose(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
|
||||
m := NewFromArrays([][]float64{
|
||||
{1, 2, 3},
|
||||
{4, 5, 6},
|
||||
{7, 8, 9},
|
||||
{10, 11, 12},
|
||||
})
|
||||
|
||||
m2 := m.Transpose()
|
||||
|
||||
rows, cols := m2.Size()
|
||||
assert.Equal(3, rows)
|
||||
assert.Equal(4, cols)
|
||||
|
||||
assert.Equal(1, m2.Get(0, 0))
|
||||
assert.Equal(10, m2.Get(0, 3))
|
||||
assert.Equal(3, m2.Get(2, 0))
|
||||
}
|
||||
45
matrix/regression.go
Normal file
45
matrix/regression.go
Normal file
|
|
@ -0,0 +1,45 @@
|
|||
package matrix
|
||||
|
||||
import "errors"
|
||||
|
||||
var (
|
||||
// ErrPolyRegArraysSameLength is a common error.
|
||||
ErrPolyRegArraysSameLength = errors.New("polynomial array inputs must be the same length")
|
||||
)
|
||||
|
||||
// Poly returns the polynomial regress of a given degree over the given values.
|
||||
func Poly(xvalues, yvalues []float64, degree int) ([]float64, error) {
|
||||
if len(xvalues) != len(yvalues) {
|
||||
return nil, ErrPolyRegArraysSameLength
|
||||
}
|
||||
|
||||
m := len(yvalues)
|
||||
n := degree + 1
|
||||
y := New(m, 1, yvalues...)
|
||||
x := Zero(m, n)
|
||||
|
||||
for i := 0; i < m; i++ {
|
||||
ip := float64(1)
|
||||
for j := 0; j < n; j++ {
|
||||
x.Set(i, j, ip)
|
||||
ip *= xvalues[i]
|
||||
}
|
||||
}
|
||||
|
||||
q, r := x.QR()
|
||||
qty, err := q.Transpose().Times(y)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
c := make([]float64, n)
|
||||
for i := n - 1; i >= 0; i-- {
|
||||
c[i] = qty.Get(i, 0)
|
||||
for j := i + 1; j < n; j++ {
|
||||
c[i] -= c[j] * r.Get(i, j)
|
||||
}
|
||||
c[i] /= r.Get(i, i)
|
||||
}
|
||||
|
||||
return c, nil
|
||||
}
|
||||
22
matrix/regression_test.go
Normal file
22
matrix/regression_test.go
Normal file
|
|
@ -0,0 +1,22 @@
|
|||
package matrix
|
||||
|
||||
import (
|
||||
"testing"
|
||||
|
||||
assert "github.com/blendlabs/go-assert"
|
||||
)
|
||||
|
||||
func TestPoly(t *testing.T) {
|
||||
assert := assert.New(t)
|
||||
var xGiven = []float64{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
|
||||
var yGiven = []float64{1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}
|
||||
var degree = 2
|
||||
|
||||
c, err := Poly(xGiven, yGiven, degree)
|
||||
assert.Nil(err)
|
||||
assert.Len(c, 3)
|
||||
|
||||
assert.InDelta(c[0], 0.999999999, DefaultEpsilon)
|
||||
assert.InDelta(c[1], 2, DefaultEpsilon)
|
||||
assert.InDelta(c[2], 3, DefaultEpsilon)
|
||||
}
|
||||
36
matrix/util.go
Normal file
36
matrix/util.go
Normal file
|
|
@ -0,0 +1,36 @@
|
|||
package matrix
|
||||
|
||||
import (
|
||||
"math"
|
||||
"strconv"
|
||||
)
|
||||
|
||||
func minInt(values ...int) int {
|
||||
min := math.MaxInt32
|
||||
|
||||
for x := 0; x < len(values); x++ {
|
||||
if values[x] < min {
|
||||
min = values[x]
|
||||
}
|
||||
}
|
||||
return min
|
||||
}
|
||||
|
||||
func maxInt(values ...int) int {
|
||||
max := math.MinInt32
|
||||
|
||||
for x := 0; x < len(values); x++ {
|
||||
if values[x] > max {
|
||||
max = values[x]
|
||||
}
|
||||
}
|
||||
return max
|
||||
}
|
||||
|
||||
func f64s(v float64) string {
|
||||
return strconv.FormatFloat(v, 'f', -1, 64)
|
||||
}
|
||||
|
||||
func roundToEpsilon(value, epsilon float64) float64 {
|
||||
return math.Nextafter(value, value)
|
||||
}
|
||||
17
matrix/vector.go
Normal file
17
matrix/vector.go
Normal file
|
|
@ -0,0 +1,17 @@
|
|||
package matrix
|
||||
|
||||
// Vector is just an array of values.
|
||||
type Vector []float64
|
||||
|
||||
// DotProduct returns the dot product of two vectors.
|
||||
func (v Vector) DotProduct(v2 Vector) (result float64, err error) {
|
||||
if len(v) != len(v2) {
|
||||
err = ErrDimensionMismatch
|
||||
return
|
||||
}
|
||||
|
||||
for i := 0; i < len(v); i++ {
|
||||
result = result + (v[i] * v2[i])
|
||||
}
|
||||
return
|
||||
}
|
||||
135
polynomial_regression_series.go
Normal file
135
polynomial_regression_series.go
Normal file
|
|
@ -0,0 +1,135 @@
|
|||
package chart
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"math"
|
||||
|
||||
"github.com/wcharczuk/go-chart/matrix"
|
||||
)
|
||||
|
||||
// PolynomialRegressionSeries implements a polynomial regression over a given
|
||||
// inner series.
|
||||
type PolynomialRegressionSeries struct {
|
||||
Name string
|
||||
Style Style
|
||||
YAxis YAxisType
|
||||
|
||||
Limit int
|
||||
Offset int
|
||||
Degree int
|
||||
InnerSeries ValueProvider
|
||||
|
||||
coeffs []float64
|
||||
}
|
||||
|
||||
// GetName returns the name of the time series.
|
||||
func (prs PolynomialRegressionSeries) GetName() string {
|
||||
return prs.Name
|
||||
}
|
||||
|
||||
// GetStyle returns the line style.
|
||||
func (prs PolynomialRegressionSeries) GetStyle() Style {
|
||||
return prs.Style
|
||||
}
|
||||
|
||||
// GetYAxis returns which YAxis the series draws on.
|
||||
func (prs PolynomialRegressionSeries) GetYAxis() YAxisType {
|
||||
return prs.YAxis
|
||||
}
|
||||
|
||||
// Len returns the number of elements in the series.
|
||||
func (prs PolynomialRegressionSeries) Len() int {
|
||||
return Math.MinInt(prs.GetLimit(), prs.InnerSeries.Len()-prs.GetOffset())
|
||||
}
|
||||
|
||||
// GetLimit returns the window size.
|
||||
func (prs PolynomialRegressionSeries) GetLimit() int {
|
||||
if prs.Limit == 0 {
|
||||
return prs.InnerSeries.Len()
|
||||
}
|
||||
return prs.Limit
|
||||
}
|
||||
|
||||
// GetEndIndex returns the effective limit end.
|
||||
func (prs PolynomialRegressionSeries) GetEndIndex() int {
|
||||
offset := prs.GetOffset() + prs.Len()
|
||||
innerSeriesLastIndex := prs.InnerSeries.Len() - 1
|
||||
return Math.MinInt(offset, innerSeriesLastIndex)
|
||||
}
|
||||
|
||||
// GetOffset returns the data offset.
|
||||
func (prs PolynomialRegressionSeries) GetOffset() int {
|
||||
if prs.Offset == 0 {
|
||||
return 0
|
||||
}
|
||||
return prs.Offset
|
||||
}
|
||||
|
||||
// Validate validates the series.
|
||||
func (prs *PolynomialRegressionSeries) Validate() error {
|
||||
if prs.InnerSeries == nil {
|
||||
return fmt.Errorf("linear regression series requires InnerSeries to be set")
|
||||
}
|
||||
|
||||
endIndex := prs.GetEndIndex()
|
||||
if endIndex >= prs.InnerSeries.Len() {
|
||||
return fmt.Errorf("invalid window; inner series has length %d but end index is %d", prs.InnerSeries.Len(), endIndex)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// GetValue returns the series value for a given index.
|
||||
func (prs *PolynomialRegressionSeries) GetValue(index int) (x, y float64) {
|
||||
if prs.InnerSeries == nil || prs.InnerSeries.Len() == 0 {
|
||||
return
|
||||
}
|
||||
|
||||
if prs.coeffs == nil {
|
||||
coeffs, err := prs.computeCoefficients()
|
||||
if err != nil {
|
||||
panic(err)
|
||||
}
|
||||
prs.coeffs = coeffs
|
||||
}
|
||||
|
||||
offset := prs.GetOffset()
|
||||
effectiveIndex := Math.MinInt(index+offset, prs.InnerSeries.Len())
|
||||
x, y = prs.InnerSeries.GetValue(effectiveIndex)
|
||||
y = prs.apply(x)
|
||||
return
|
||||
}
|
||||
|
||||
func (prs *PolynomialRegressionSeries) apply(v float64) (out float64) {
|
||||
for index, coeff := range prs.coeffs {
|
||||
out = out + (coeff * math.Pow(v, float64(index)))
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
func (prs *PolynomialRegressionSeries) computeCoefficients() ([]float64, error) {
|
||||
xvalues, yvalues := prs.values()
|
||||
return matrix.Poly(xvalues, yvalues, prs.Degree)
|
||||
}
|
||||
|
||||
func (prs *PolynomialRegressionSeries) values() (xvalues, yvalues []float64) {
|
||||
startIndex := prs.GetOffset()
|
||||
endIndex := prs.GetEndIndex()
|
||||
|
||||
xvalues = make([]float64, endIndex-startIndex)
|
||||
yvalues = make([]float64, endIndex-startIndex)
|
||||
|
||||
for index := startIndex; index < endIndex; index++ {
|
||||
x, y := prs.InnerSeries.GetValue(index)
|
||||
xvalues[index] = x
|
||||
yvalues[index] = y
|
||||
}
|
||||
|
||||
return
|
||||
}
|
||||
|
||||
// Render renders the series.
|
||||
func (prs *PolynomialRegressionSeries) Render(r Renderer, canvasBox Box, xrange, yrange Range, defaults Style) {
|
||||
style := prs.Style.InheritFrom(defaults)
|
||||
Draw.LineSeries(r, canvasBox, xrange, yrange, style, prs)
|
||||
}
|
||||
Loading…
Reference in a new issue