--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/globalneighbors/grid.py	Sat Jun 24 12:03:39 2017 -0700
@@ -0,0 +1,37 @@
+import math
+
+class LatLonGrid(object):
+
+    lat_range = (-90., 90)
+    lon_range = (-180., 180)  # however, this wraps around
+
+    def __init__(self, nlat, nlon):
+        self.n = (nlat, nlon)
+        self.range = (self.lat_range, self.lon_range)
+        self.d = ((self.lat_range[-1] - self.lat_range[0])/self.n[0],
+                  (self.lon_range[-1] - self.lon_range[0])/self.n[1])
+        self.create_grid()
+
+    def create_grid(self):
+        self.grid = [[] for _ in xrange(self.n[-1])
+                     for _ in xrange(self.n[0])]
+
+    def add(self, geoid, lat, lon):
+        latlon = (lat, lon)
+        self[self.index(lat, lon)].append(geoid)
+
+    def __getitem__(self, index):
+        """
+        index -- 2-tuple or list of i and j indices
+        """
+        import pdb; pdb.set_trace()
+        return self.grid[index[0]][index[1]]
+
+    def index(self, lat, lon):
+        return [int(math.floor((val-self.range[i][0])/self.d[i]))
+                for i, val in enumerate((lat, lon))]
+
+    def neighbors(self, i, j):
+        """
+        return neighbors of points i, j
+        """