chunks: helper for bit range

This commit is contained in:
Fabian Reinartz 2016-12-07 15:37:37 +01:00
parent 9b459458d0
commit c5945177fb
2 changed files with 13 additions and 9 deletions

View File

@ -94,10 +94,10 @@ func benchmarkIterator(b *testing.B, newChunk func(int) Chunk) {
)
var exp []pair
for i := 0; i < b.N; i++ {
// t += int64(rand.Intn(10000) + 1)
t += int64(1000)
t += int64(rand.Intn(10000) + 1)
// t += int64(1000)
// v = rand.Float64()
// v += float64(100)
v += float64(100)
exp = append(exp, pair{t: t, v: v})
}
@ -161,10 +161,10 @@ func benchmarkAppender(b *testing.B, newChunk func(int) Chunk) {
)
var exp []pair
for i := 0; i < b.N; i++ {
// t += int64(rand.Intn(10000) + 1)
t += int64(1000)
t += int64(rand.Intn(10000) + 1)
// t += int64(1000)
// v = rand.Float64()
// v += float64(100)
v += float64(100)
exp = append(exp, pair{t: t, v: v})
}

View File

@ -120,13 +120,13 @@ func (a *xorAppender) Append(t int64, v float64) error {
switch {
case dod == 0:
a.b.writeBit(zero)
case -8191 <= dod && dod <= 8192:
case bitRange(dod, 14):
a.b.writeBits(0x02, 2) // '10'
a.b.writeBits(uint64(dod), 14)
case -65535 <= dod && dod <= 65536:
case bitRange(dod, 17):
a.b.writeBits(0x06, 3) // '110'
a.b.writeBits(uint64(dod), 17)
case -524287 <= dod && dod <= 524288:
case bitRange(dod, 20):
a.b.writeBits(0x0e, 4) // '1110'
a.b.writeBits(uint64(dod), 20)
default:
@ -152,6 +152,10 @@ func (a *xorAppender) Append(t int64, v float64) error {
return nil
}
func bitRange(x int64, nbits uint8) bool {
return -((1<<(nbits-1))-1) <= x && x <= 1<<(nbits-1)
}
func (a *xorAppender) writeVDelta(v float64) {
vDelta := math.Float64bits(v) ^ math.Float64bits(a.v)