tasks a-s

Task/Polynomial-regression/Go/polynomial-regression.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+    "code.google.com/p/gomatrix/matrix"
+    "fmt"
+)
+
+var xGiven = []float64{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
+var yGiven = []float64{1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321}
+var degree = 2
+
+func main() {
+    m := len(yGiven)
+    n := degree + 1
+    y := matrix.MakeDenseMatrix(yGiven, m, 1)
+    x := matrix.Zeros(m, n)
+    for i := 0; i < m; i++ {
+        ip := float64(1)
+        for j := 0; j < n; j++ {
+            x.Set(i, j, ip)
+            ip *= xGiven[i]
+        }
+    }
+
+    q, r := x.QR()
+    qty, err := q.Transpose().Times(y)
+    if err != nil {
+        fmt.Println(err)
+        return
+    }
+    c := make([]float64, n)
+    for i := n - 1; i >= 0; i-- {
+        c[i] = qty.Get(i, 0)
+        for j := i + 1; j < n; j++ {
+            c[i] -= c[j] * r.Get(i, j)
+        }
+        c[i] /= r.Get(i, i)
+    }
+    fmt.Println(c)
+}