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
}
}
}
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)
}