Create geohash-ii.py

yingl · web-flow · commit 353d22fedc12 · 2022-02-10T21:16:49.000+08:00
diff --git a/geohash-ii.py b/geohash-ii.py
@@ -0,0 +1,39 @@
+class GeoHash:
+    """
+    @param: geohash: geohash a base32 string
+    @return: latitude and longitude a location coordinate pair
+    """
+    def decode(self, geohash):
+        # write your code here
+        code = self.b32decode(geohash)
+        longs, lats = [-180, 180], [-90, 90]
+        longtitude, latitude = 0, 0
+        prec = len(code)
+        for i in range(0, prec, 2):
+            if code[i] == '0':
+                longs[1] = longtitude
+            else:
+                longs[0] = longtitude
+            longtitude = (longs[0] + longs[1]) / 2
+            if (i + 1) >= prec:
+                break
+            if code[i + 1] == '0':
+                lats[1] = latitude
+            else:
+                lats[0] = latitude
+            latitude = (lats[0] + lats[1]) / 2
+        return (latitude, longtitude)
+
+    def b32decode(self, geohash):
+        r = ''
+        bcode = {'0': '00000', '1': '00001', '2': '00010', '3': '00011',
+                 '4': '00100', '5': '00101', '6': '00110', '7': '00111',
+                 '8': '01000', '9': '01001', 'b': '01010', 'c': '01011',
+                 'd': '01100', 'e': '01101', 'f': '01110', 'g': '01111',
+                 'h': '10000', 'j': '10001', 'k': '10010', 'm': '10011',
+                 'n': '10100', 'p': '10101', 'q': '10110', 'r': '10111',
+                 's': '11000', 't': '11001', 'u': '11010', 'v': '11011',
+                 'w': '11100', 'x': '11101', 'y': '11110', 'z': '11111'}
+        for c in geohash:
+            r += bcode[c]
+        return r
