bbgo_origin/pkg/indicator/macd2.go
2023-05-30 13:50:59 +08:00

75 lines
1.4 KiB
Go

package indicator
import (
"github.com/c9s/bbgo/pkg/datatype/floats"
"github.com/c9s/bbgo/pkg/types"
)
/*
NEW INDICATOR DESIGN:
klines := kLines(marketDataStream)
closePrices := closePrices(klines)
macd := MACD(klines, {Fast: 12, Slow: 10})
equals to:
klines := KLines(marketDataStream)
closePrices := ClosePrice(klines)
fastEMA := EMA(closePrices, 7)
slowEMA := EMA(closePrices, 25)
macd := Subtract(fastEMA, slowEMA)
signal := EMA(macd, 16)
histogram := Subtract(macd, signal)
*/
type Float64Source interface {
types.Series
OnUpdate(f func(v float64))
}
type Float64Subscription interface {
types.Series
AddSubscriber(f func(v float64))
}
//go:generate callbackgen -type EWMAStream
type EWMAStream struct {
Float64Updater
types.SeriesBase
slice floats.Slice
window int
multiplier float64
}
func EWMA2(source Float64Source, window int) *EWMAStream {
s := &EWMAStream{
window: window,
multiplier: 2.0 / float64(1+window),
}
s.SeriesBase.Series = s.slice
if sub, ok := source.(Float64Subscription); ok {
sub.AddSubscriber(s.calculateAndPush)
} else {
source.OnUpdate(s.calculateAndPush)
}
return s
}
func (s *EWMAStream) calculateAndPush(v float64) {
v2 := s.calculate(v)
s.slice.Push(v2)
s.EmitUpdate(v2)
}
func (s *EWMAStream) calculate(v float64) float64 {
last := s.slice.Last()
m := s.multiplier
return (1.0-m)*last + m*v
}