Merge naive python solution (Brice)

Author: bricef

01-Simple-Linear-Regression/python-naive/main.py

@@ -0,0 +1,56 @@
+#!/usr/bin/env python
+
+import resource
+
+
+points = []
+
+with open("../data/ex2x.dat", 'r') as fx:
+  with open("../data/ex2y.dat", 'r') as fy:
+    xs = [float(xi) for xi in fx.readlines()]
+    ys = [float(yi) for yi in fy.readlines()]
+    points = zip(xs,ys) 
+
+def RSS(points, fn):
+  return sum([ (fn(x)-y)**2 for (x,y) in points])
+
+def linear(a,c):
+  def fn(x):
+    return (a*x)+c
+  return fn
+
+step = 0.00001
+
+a0 = 0.0
+c0 = 0.0
+
+def solve(points,a,c):
+  rss = RSS(points, linear(a,c))
+
+  candidates = [
+    (a+step, c),
+    (a-step,c),
+    (a,c+step),
+    (a,c-step),
+    (a-step,c-step),
+    (a+step,c-step),
+    (a+step,c+step),
+    (a-step,c+step)
+  ]
+  
+  best = min([
+    (RSS(points, linear(a,c)),a,c) for a,c in candidates])
+  return best
+
+rss = RSS(points, linear(a0,c0))
+best = solve(points,a0,c0)
+
+while best[0] < rss: 
+  rss = RSS(points, linear(best[1], best[2]))
+  best = solve(points, best[1], best[2])
+
+rss,a,c = best
+
+print(
+  "y={}x + {}".format(a,c)
+)