| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| type point = < X: double, Y: double >; |
| |
| function distance ( x: point, y: point ): double { |
| sqrt(pow(x.X-y.X,2)+pow(x.Y-y.Y,2)) |
| }; |
| |
| aggregation new_centroid ( |
| \(p:(point,long),q:(point,long)):(point,long) |
| .( < X: p#0.X+q#0.X, Y: p#0.Y+q#0.Y >, |
| p#1+q#1), |
| ( < X: 0.0 as double, Y :0.0 as double >, 0 as long ) |
| ) : (point,long); |
| |
| function centroid ( p: (point,long), default: point ): point { |
| if p#1 = 0 |
| then default |
| else < X: p#0.X/p#1, Y: p#0.Y/p#1 > |
| }; |
| |
| repeat centroids = { < X: 0.0 as double, Y: 0.0 as double >, |
| < X: 10.0, Y: 0.0 >, |
| < X: 0.0, Y: 10.0 >, |
| < X: 10.0, Y: 10.0 > } |
| step select ( centroid(new_centroid(select (p,1 as long) from p in s),k), true ) |
| from s in source(binary,"points.bin") |
| group by k: (select c from c in centroids order by distance(c,s))[0] |
| limit 5; |