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expdecay.go
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/
expdecay.go
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package blockchain
/*
import "math/big"
// Root is a high precision arbitrary fractional root function used for the post p9 hardfork reward calculation
func Root(a *big.Float, n float64) *big.Float {
limit := Exp(New(2), 256)
n1 := n - 1
n1f, rn := New(float64(n1)), Div(New(1.0), New(float64(n)))
x, x0 := New(1.0), Zero()
_ = x0
for {
potx, t2 := Div(New(1.0), x), a
for b := n1; b > 0; b >>= 1 {
if b&1 == 1 {
t2 = Mul(t2, potx)
}
potx = Mul(potx, potx)
}
x0, x = x, Mul(rn, Add(Mul(n1f, x), t2))
if Lesser(Mul(Abs(Sub(x, x0)), limit), x) {
break
}
}
return x
}
func Abs(a *big.Float) *big.Float {
return Zero().Abs(a)
}
func Exp(a *big.Float, e uint64) *big.Float {
result := Zero().Copy(a)
for i := uint64(0); i < e-1; i++ {
result = Mul(result, a)
}
return result
}
func New(f float64) *big.Float {
r := big.NewFloat(f)
r.SetPrec(256)
return r
}
func Div(a, b *big.Float) *big.Float {
return Zero().Quo(a, b)
}
func Zero() *big.Float {
r := big.NewFloat(0.0)
r.SetPrec(256)
return r
}
func Mul(a, b *big.Float) *big.Float {
return Zero().Mul(a, b)
}
func Add(a, b *big.Float) *big.Float {
return Zero().Add(a, b)
}
func Sub(a, b *big.Float) *big.Float {
return Zero().Sub(a, b)
}
func Lesser(x, y *big.Float) bool {
return x.Cmp(y) == -1
}
*/