Example #1
0
func testUint(t *testing.T, n int) {
	values := make([]uint, n)
	for i := range values {
		values[i] = uint(rand.Int())
	}

	var buf bytes.Buffer
	w := bit.NewWriter(&buf)
	for _, v := range values {
		WriteUint(w, v)
	}

	err := w.Close()
	if err != nil {
		t.Errorf("w.Close: %v", err)
		return
	}

	r := bit.NewReader(&buf)
	for i, exp := range values {
		got, err := ReadUint(r), r.Error()
		if err != nil {
			t.Errorf("ReadUint: %v", err)
			return
		}
		if got != exp {
			t.Errorf("%v: %d got %v expected %v", values, i, got, exp)
			return
		}
	}
}
Example #2
0
func main() {
	flag.Parse()
	filename := flag.Arg(0)

	for i := range byteCount {
		byteCount[i] = bit.Count(uint64(i))
	}

	data, err := ioutil.ReadFile(filename)
	check(err)

	bitcount := 0
	for _, b := range data {
		bitcount += byteCount[b]
	}
	fmt.Printf("bit bias: %.4f\n", float64(bitcount)/float64(len(data)*8))

	r := bit.NewReader(bytes.NewReader(data))
	circle := byte(0)

	count2 := make(map[byte]int)
	count3 := make(map[byte]int)
	count4 := make(map[byte]int)
	count5 := make(map[byte]int)
	count6 := make(map[byte]int)
	count7 := make(map[byte]int)
	count8 := make(map[byte]int)

	var v int
	for r.Error() == nil {
		v = r.ReadBit()
		circle <<= 1
		circle |= byte(v)

		count2[circle&(1<<2-1)] += 1
		count3[circle&(1<<3-1)] += 1
		count4[circle&(1<<4-1)] += 1
		count5[circle&(1<<5-1)] += 1
		count6[circle&(1<<6-1)] += 1
		count7[circle&(1<<7-1)] += 1
		count8[circle&(1<<8-1)] += 1
	}

	PrintFrequency("2", count2, data)
	PrintFrequency("3", count3, data)
	PrintFrequency("4", count4, data)
	PrintFrequency("5", count5, data)
	PrintFrequency("6", count6, data)
	PrintFrequency("7", count7, data)
	PrintFrequency("8", count8, data)
}