RosettaCodeData/Task/Minkowski-question-mark-fun.../Go/minkowski-question-mark-fun...

106 lines
2.2 KiB
Go

package main
import (
"fmt"
"math"
)
const MAXITER = 151
func minkowski(x float64) float64 {
if x > 1 || x < 0 {
return math.Floor(x) + minkowski(x-math.Floor(x))
}
p := uint64(x)
q := uint64(1)
r := p + 1
s := uint64(1)
d := 1.0
y := float64(p)
for {
d = d / 2
if y+d == y {
break
}
m := p + r
if m < 0 || p < 0 {
break
}
n := q + s
if n < 0 {
break
}
if x < float64(m)/float64(n) {
r = m
s = n
} else {
y = y + d
p = m
q = n
}
}
return y + d
}
func minkowskiInv(x float64) float64 {
if x > 1 || x < 0 {
return math.Floor(x) + minkowskiInv(x-math.Floor(x))
}
if x == 1 || x == 0 {
return x
}
contFrac := []uint32{0}
curr := uint32(0)
count := uint32(1)
i := 0
for {
x *= 2
if curr == 0 {
if x < 1 {
count++
} else {
i++
t := contFrac
contFrac = make([]uint32, i+1)
copy(contFrac, t)
contFrac[i-1] = count
count = 1
curr = 1
x--
}
} else {
if x > 1 {
count++
x--
} else {
i++
t := contFrac
contFrac = make([]uint32, i+1)
copy(contFrac, t)
contFrac[i-1] = count
count = 1
curr = 0
}
}
if x == math.Floor(x) {
contFrac[i] = count
break
}
if i == MAXITER {
break
}
}
ret := 1.0 / float64(contFrac[i])
for j := i - 1; j >= 0; j-- {
ret = float64(contFrac[j]) + 1.0/ret
}
return 1.0 / ret
}
func main() {
fmt.Printf("%19.16f %19.16f\n", minkowski(0.5*(1+math.Sqrt(5))), 5.0/3.0)
fmt.Printf("%19.16f %19.16f\n", minkowskiInv(-5.0/9.0), (math.Sqrt(13)-7)/6)
fmt.Printf("%19.16f %19.16f\n", minkowski(minkowskiInv(0.718281828)),
minkowskiInv(minkowski(0.1213141516171819)))
}