Question

我正在构建一个与Google Places API交互的程序，以识别美国郡内某个类型的所有机构。谷歌接受半径形式的搜索 - 所以为了覆盖整个区域，我正在逐步建立我的搜索半径。但是，这个算法创建了很多重叠的圆圈，我想过滤掉。所以：

给出一个圆圈列表，每个圆圈的中心和半径，如何判断一个圆圈是否被其他圆圈的任何组合完全覆盖？

我已经可以判断一个圆圈是否被另一个圆圈包围 - 我的问题是很多圈子被其他几个圈子所包围。

有人要求我现有的代码 - 如果一个圆圈与另一个圆圈完全重叠而不是它们的组合，我目前测试的代码。但这就是我所拥有的。您可以看到，如果它与其他20个圆圈重叠，我可以将其排除在当前问题之外，此时它可能包含在内：

def radiusIsInsidePreviousQuery(self, testQuery):
    newSearchCoordinates = (testQuery['center']['lat'], testQuery['center']['lng'])
    alreadyBeenSearched = False

    numberOfIntersectingCircles = 0

    for queryNumber in self.results.keys():
        previousQuery = self.results[queryNumber]
        previousSearchCoordinates = (previousQuery['center']['lat'], 
                                     previousQuery['center']['lng'])

        centroidDistance = VincentyDistance(newSearchCoordinates, 
                                            previousSearchCoordinates)

        centroidDistanceMeters = centroidDistance.meters
        newQueryRadius = testQuery['radius']
        fullSearchDistance = centroidDistanceMeters + newQueryRadius

        #If the full search distance (the sum of the distance between
        #the two searches' centroids and the new search's radius) is less
        #than the previous search's radius, then the new search is encompassed
        #entirely by the old search.
        previousQueryRadius = previousQuery['radius']
        if fullSearchDistance <= previousQueryRadius:
            print "Search area encompassed"
            alreadyBeenSearched = True
        elif centroidDistanceMeters < newQueryRadius + previousQueryRadius:
            numberOfIntersectingCircles += 1
        elif self.queriesAreEqual(testQuery, previousQuery):
            print "found duplicate"
            alreadyBeenSearched = True   

    #If it intersects with 20 other circles, it's not doing any more good.
    if numberOfIntersectingCircles > 20:
        alreadyBeenSearched = True    

    return alreadyBeenSearched

Answer 1

让我们考虑要测试的圆A.

我不知道你的计算需要多精确，但我们假设用100分代表A的周长就足够了。

导入数学

max(marglik{1})==marglik{1}

如何判断一个圆是否包含在其他几个圆圈中

1 个答案: