Data commit

Task/Minkowski-question-mark-function/Go/minkowski-question-mark-function.go

@@ -0,0 +1,105 @@
+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)))
+}