Graph.go

package randAlgs

import "log"

// IndMatrix represents a graph as incidence matrix.
type IndMatrix struct {
	Dim    int
	Values []int // dim * dim values expected
}

// CreateEmptyIndMatrix returns empty IndMatrix of given dimension.
func CreateEmptyIndMatrix(dim int) IndMatrix {
	values := make([]int, 0, dim)
	return IndMatrix{dim, values}
}

func (im *IndMatrix) AddRow(values []int) {
	if len(values) != im.Dim {
		log.Printf("[AddRow] Expected %d values, got %d \n.", im.Dim, len(values))
	}

	for _, e := range values[0:im.Dim] {
		im.Values = append(im.Values, e)
	}
}

// Returns i-th row of IndMatrix.
func (im *IndMatrix) GetRowValues(i int) []int {
	return make([]int, 0)
}

// Returns i-th col of IndMatrix.
func (im *IndMatrix) GetColValues(i int) []int {
	return make([]int, 0)
}

func CreateEmptyIndMatrix() IndMatrix {

}

func (im *IndMatrix) GetRowIndex(i int) int {
	return im.dim * i
}

// Returns i-th row of IndMatrix.
func (im *IndMatrix) GetRow(i int) []*int {
	startIndex := im.GetRowIndex(i)
	endIndex := im.GetRowIndex(i)*im.dim - 1
	return im[startIndex:endIndex]
}
func (im *IndMatrix) AddTwoRows(i int, j int) {
	startIndexToRemove := im.GetRowIndex(i)
	endIndexToRemove := im.GetRowIndex(i) + im.dim - 1
	startIndexToKeep := im.GetRowIndex(i)
	endIndexToKeep := im.GetRowIndex(i) + im.dim - 1

	newRow := im[startIndexToKeep:endIndexToKeep] + im[startIndexToRemove:endIndexToRemove]
	im[startIndexToRemove:endIndexToRemove] = nil
	im[startIndexToRemove:endIndexToRemove] = newRow
}