trace.go

package main

type Trace struct {
	Data [][]int64
	Cols int
}

func NewTrace(data [][]int64) Trace {
	return Trace{Data: data, Cols: len(data[0])}
}

func (t Trace) Rows() int          { return len(t.Data) }
func (t Trace) Get(r, c int) int64 { return t.Data[r][c] }
func (t Trace) Col(c int) []int64 {
	r := make([]int64, len(t.Data))
	for i := range t.Data {
		r[i] = t.Data[i][c]
	}
	return r
}

func FibonacciTrace(steps int) Trace {
	data := make([][]int64, steps)
	for i := range data {
		switch i {
		case 0:
			data[i] = []int64{0, 1, 1}
		case 1:
			data[i] = []int64{1, 1, 1}
		default:
			f2, f1 := data[i-1][1], data[i-1][2]
			data[i] = []int64{f2, f1, f1 + f2}
		}
	}
	return NewTrace(data)
}