Add Otsuka-Ochiai coefficient

otsuka.py

@@ -0,0 +1,20 @@
+# $K = \frac{|A \cap B|}{\sqrt{|A| \times |B|}}$
+def otsuka_sim(known_point, new_point):
+    from math import sqrt
+    up, d1, d2 = 0.0, 0.0, 0.0
+    a, b = known_point, new_point
+    for key in a.wifi_snr:
+        d1 += 1
+        if key in b.wifi_snr:
+            up += 1
+    for key in b.wifi_snr:
+        d2 += 1
+    if up == 0:
+        return None
+    else:
+        return up / sqrt(d1) / sqrt(d2)
+
+if __name__ == '__main__':
+    from wifiloc import toplev
+    toplev(infile = "basicdata.csv", sim = otsuka_sim, bad_wifi_crit = 5000,
+            sim_crit = 0.0)