changes cluster centers to json

src/py/crankshaft/crankshaft/clustering/kmeans.py

@@ -40,6 +40,7 @@ def kmeans_nonspatial(query, colnames, num_clusters=5,
         num_clusters (int): number of clusters (greater than zero)
         id_col (string): name of the input id_column
     """
+    import json
     out_id_colname = 'rowids'
     # TODO: need a random seed?
 
@@ -60,7 +61,7 @@ def kmeans_nonspatial(query, colnames, num_clusters=5,
     # fill array with values for k-means clustering
     if standarize:
         cluster_columns = _scale_data(
-          _extract_columns(db_resp, id_col=out_id_colname))
+          _extract_columns(db_resp, out_id_colname))
     else:
         cluster_columns = _extract_columns(db_resp, id_col=out_id_colname)
 
@@ -69,8 +70,9 @@ def kmeans_nonspatial(query, colnames, num_clusters=5,
     kmeans = KMeans(n_clusters=num_clusters,
                     random_state=0).fit(cluster_columns)
 
+    centers = [json.dumps(dict(zip(colnames, c))) for c in kmeans.cluster_centers_[kmeans.labels_]]
     return zip(kmeans.labels_,
-               map(str, kmeans.cluster_centers_[kmeans.labels_]),
+               centers,
                db_resp[0][out_id_colname])