Hi ZhiQiang, the examples you show are SCC of only 1 node, but the original example is not a SCC I think, as you have an outgoing and an incoming edge. So I guess this is a bug or something. Maybe you can provide a failing and small unit test for this so that I can have a look?
Also the step 4 is indeed only for informational purposes but will print new information if the step 3 changed the subnetworks. Regards, Peter On 29.07.2015 11:44, John Zhao wrote: > Hi Peter, > > There are a lot of SCC with only 1 node, like: > http://www.openstreetmap.org/node/1707762331 > http://www.openstreetmap.org/node/386885888 > http://www.openstreetmap.org/node/364825950 > > Step 4 is only to findSubnetwork(), and print some info, not removal them. > So, step 4 is optional. > > Now I only understand why this happen. :( > > > *Best Regards,* > *ZhiQiang ZHAO* > > On Wed, Jul 29, 2015 at 2:28 AM, Peter <[email protected] > <mailto:[email protected]>> wrote: > > Hi ZhiQiang, > > > And the http://www.openstreetmap.org/node/678314919 itself is a > SCC. size is 1. > > It shouldn't be a SCC im my opinion - is there a bug? > If it is not a bug - do you have a suggestion for this, like > avoiding step 4? > > Regards, > Peter > > > > On 29.07.2015 11:18, John Zhao wrote: >> Hi Peter, >> >> The parameter I set are minOnewayNetworkSize = 20, minNetworkSize >> = 200 >> >> on step 3, despite the >> node http://www.openstreetmap.org/node/678314919, the inside >> island is a SCC, and the size is larger than 20. >> So, this island is kept, instead of removal. >> And the http://www.openstreetmap.org/node/678314919 itself is a >> SCC. size is 1. Then it was removed. >> >> Then on step 4, the island is recognized as a subnetwork, which >> has size less than 200. >> >> *Best Regards,* >> *ZhiQiang ZHAO* >> >> On Wed, Jul 29, 2015 at 1:04 AM, Peter <[email protected] >> <mailto:[email protected]>> wrote: >> >> Hi ZhiQiang, >> >> you mean the oneway procedure (step 3) removes nodes+edges >> leading to further normal subnetwork removal in step 4? This >> should not happen. The subnetwork should be removed already >> in step 3. >> >> > On step 2, although there is a gate >> http://www.openstreetmap.org/node/703042503 >> > on http://www.openstreetmap.org/way/6374339 >> > And gate block that edge. >> >> Because of this gate the island is a oneway subnetwork (!) >> and should get entirely removed in step 2 IMO. >> >> > On step 3, a very important point are removed due to oneway >> >> If just one edge/node is removed there is something wrong. >> The whole island should be removed. >> >> Kind Regards, >> Peter >> >> >> On 29.07.2015 09:50, John Zhao wrote: >>> Hi Peter, >>> >>> I know the difference between subnetworks and >>> oneway-subnetworks. >>> I am talking about the step 2 and step 4, not step 3. >>> >>> step 2 and step 4 are both findSubnetwork() with the same >>> parameter. >>> minOnewayNetworkSize = 20, minNetworkSize = 200 >>> >>> I think I figure out why this discrepancy occurs. >>> One case is a island in SF bay area. The island has 2 oneway >>> roads connected to the main network. >>> http://www.openstreetmap.org/way/53726398 >>> http://www.openstreetmap.org/way/6374339 >>> >>> On step 2, although there is a >>> gate http://www.openstreetmap.org/node/703042503 >>> on http://www.openstreetmap.org/way/6374339 >>> And gate block that edge. >>> The other oneway is connected >>> http://www.openstreetmap.org/way/53726398. >>> So, this island is connected to the whole network. >>> >>> On step 3, a very important point are removed due to >>> oneway: http://www.openstreetmap.org/node/678314919 >>> >>> Then on step 4, the island are not connected to the main >>> network. >>> >>> *Best Regards,* >>> *ZhiQiang ZHAO* >>> >>> On Tue, Jul 28, 2015 at 11:12 PM, Peter <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> Hi ZhiQiang, >>> >>> hmmh, not sure if I understand what is unknown at your side. >>> >>> Subnetworks are different things than >>> oneway-subnetworks. For example 4-5 is a oneway >>> subnetwork if connect with a oneway to the main graph only: >>> mainGraph->4-5 >>> >>> And this cannot be detected in step 2. >>> >>> Please have a look at the unit tests to see more >>> examples for the different scenes >>> >>> Regards, >>> Peter >>> >>> >>> On 28.07.2015 20:05, John Zhao wrote: >>>> Hi Peter, >>>> >>>> the result I posted is not the result of >>>> oneway-subnetwork procedure. >>>> >>>> The total procedures include: >>>> 1. remove zero-degree node >>>> 2. findSubnetwork >>>> 3. oneway-subnetwork procedure >>>> 4. findSubnetwork again on graphhopper.cleanup() >>>> >>>> My question is, why those islands are recognized on >>>> step 4, but not on step 2? >>>> >>>> >>>> >>>> *Best Regards,* >>>> *ZhiQiang ZHAO* >>>> >>>> On Tue, Jul 28, 2015 at 12:02 AM, Peter >>>> <[email protected] <mailto:[email protected]>> wrote: >>>> >>>> Hi ZhiQiang, >>>> >>>> I think it is because both networks are oneway >>>> subnetworks not found by the normal subnetwork >>>> procedure (but by the oneway-subnetwork procedure) >>>> and you defined the oneway minimum size to 20 >>>> >>>> Regards, >>>> Peter >>>> >>>> >>>> On 28.07.2015 03:13, John Zhao wrote: >>>>> Hi Peter, >>>>> >>>>> What I do is: >>>>> 1. minOnewayNetworkSize = 20, minNetworkSize = 200 >>>>> 2. build san francisco bay area osm data >>>>> 3. I print out the subnetworks result of the >>>>> second call. >>>>> int remainingSubnetworks = >>>>> preparation.findSubnetworks().size(); >>>>> 4. I found the subnetwork has some smaller than 200, like: >>>>> subnetwork start from: >>>>> 37.32611992939085,-121.9961998312816 size: 24 >>>>> subnetwork start from: >>>>> 37.78373608999855,-122.25065187925067 size: 34 >>>>> >>>>> 5. I can't understand why the subnetworks with 24 nodes >>>>> and 34 nodes are not removed by preparation.doWork(); >>>>> It call the same method: >>>>> Map map = this.findSubnetworks(); >>>>> >>>>> >>>>> *Best Regards,* >>>>> *ZhiQiang ZHAO* >>>>> >>>>> On Mon, Jul 27, 2015 at 12:54 PM, Peter >>>>> <[email protected] <mailto:[email protected]>> >>>>> wrote: >>>>> >>>>> Hi John, >>>>> >>>>> sorry, I do not understand your problem or >>>>> question here. Would you describe it again >>>>> step by step for me :) ? >>>>> >>>>> Kind Regards, >>>>> Peter >>>>> >>>>> >>>>> On 27.07.2015 21:45, John Zhao wrote: >>>>>> Hi Peter, >>>>>> >>>>>> Thanks. >>>>>> Actually I only have 1 flagEncoder in >>>>>> the EncodingManager. >>>>>> The call is exact >>>>>> same, preparation.findSubnetworks() >>>>>> preparation.findSubnetworks() using edgeFilter which >>>>>> is also from singleEncoder. >>>>>> >>>>>> *Best Regards,* >>>>>> *ZhiQiang ZHAO* >>>>>> >>>>>> On Sun, Jul 26, 2015 at 7:56 AM, Peter >>>>>> <[email protected] >>>>>> <mailto:[email protected]>> wrote: >>>>>> >>>>>> Hi John, >>>>>> >>>>>> it should not be related to calling these >>>>>> method twice. It is just one time where >>>>>> you calculate the subnetworks independent >>>>>> of any FlagEncoder or direction via >>>>>> findSubnetworks and the second pass is >>>>>> FlagEncoder- and access-dependent via >>>>>> removeDeadEndUnvisitedNetworks. >>>>>> >>>>>> Regards, >>>>>> Peter >>>>>> >>>>>> >>>>>> On 24.07.2015 21:16, John Zhao wrote: >>>>>>> Hi Peter, >>>>>>> >>>>>>> I am still confused. >>>>>>> at first we call >>>>>>> map = findSubnetworks(); >>>>>>> >>>>>>> after the cleanup, we call the same >>>>>>> method in Graphhopper. >>>>>>> int remainingSubnetworks = >>>>>>> preparation.findSubnetworks().size(); >>>>>>> Why the subnetwork was recognized the latter >>>>>>> time, but not the first time? >>>>>>> we remove some edges make it not connected? >>>>>>> >>>>>>> *Best Regards,* >>>>>>> *ZhiQiang ZHAO* >>>>>>> >>>>>>> On Thu, Jul 23, 2015 at 2:22 PM, Peter >>>>>>> <[email protected] >>>>>>> <mailto:[email protected]>> wrote: >>>>>>> >>>>>>> >>>>>>> Hi ZhiQiang, >>>>>>> >>>>>>> yes, according to the wiki this is >>>>>>> wrongly mapped: >>>>>>> /Avoid tagging highway intersections >>>>>>> as that does not make clear which >>>>>>> way has the impediment. / >>>>>>> >>>>>>> >>>>>>> http://wiki.openstreetmap.org/wiki/Tag:barrier%3Dgate >>>>>>> >>>>>>> Peter >>>>>>> >>>>>>> >>>>>>> On 23.07.2015 23:16, John Zhao wrote: >>>>>>>> Hi Peter, >>>>>>>> >>>>>>>> Maybe the following one related >>>>>>>> with >>>>>>>> https://github.com/graphhopper/graphhopper/issues/388#issuecomment-88066385 >>>>>>>> >>>>>>>> >>>>>>>> I have a look >>>>>>>> at 37.32611992939085,-121.9961998312816. >>>>>>>> It seesm related with barrier=gate >>>>>>>> at intersection. >>>>>>>> >>>>>>>> http://www.openstreetmap.org/node/1126492194 >>>>>>>> >>>>>>>> *Best Regards,* >>>>>>>> *ZhiQiang ZHAO* >>>>>>>> >>>>>>>> On Thu, Jul 23, 2015 at 2:11 PM, >>>>>>>> Peter <[email protected] >>>>>>>> <mailto:[email protected]>> wrote: >>>>>>>> >>>>>>>> >>>>>>>> There are two types of >>>>>>>> subnetworks and the smaller >>>>>>>> ones seems to be 'one-way >>>>>>>> subnetworks' which means they >>>>>>>> are eg. only reachable as >>>>>>>> destination or start. But if >>>>>>>> you would start from a >>>>>>>> destination-only subnetwork >>>>>>>> you'll get 'not found' for all >>>>>>>> points outside of this network. >>>>>>>> >>>>>>>> Regards, >>>>>>>> Peter >>>>>>>> >>>>>>>> >>>>>>>> On 23.07.2015 23:03, John Zhao >>>>>>>> wrote: >>>>>>>>> Interesting, >>>>>>>>> when I >>>>>>>>> increase minOnewayNetworkSize >>>>>>>>> from 20 to 50, the following >>>>>>>>> two disappeared. >>>>>>>>> subnetwork start from: >>>>>>>>> 37.32611992939085,-121.9961998312816 >>>>>>>>> size: 24 >>>>>>>>> subnetwork start from: >>>>>>>>> 37.78373608999855,-122.25065187925067 >>>>>>>>> size: 34 >>>>>>>>> >>>>>>>>> *Best Regards,* >>>>>>>>> *ZhiQiang ZHAO* >>>>>>>>> >>>>>>>>> On Thu, Jul 23, 2015 at 1:55 >>>>>>>>> PM, John Zhao >>>>>>>>> <[email protected] >>>>>>>>> <mailto:[email protected]>> wrote: >>>>>>>>> >>>>>>>>> Hi, >>>>>>>>> >>>>>>>>> I tried car flag encoder >>>>>>>>> with following parameter >>>>>>>>> on San Francisco bay area >>>>>>>>> data from mapzen. >>>>>>>>> >>>>>>>>> https://s3.amazonaws.com/metro-extracts.mapzen.com/san-francisco-bay_california.osm.pbf >>>>>>>>> >>>>>>>>> minNetworkSize=200 >>>>>>>>> minOnewayNetworkSize=20 >>>>>>>>> >>>>>>>>> I printed all the >>>>>>>>> remaining subnetworks. >>>>>>>>> edges: 591932, nodes >>>>>>>>> 437420, there were 3496 >>>>>>>>> subnetworks. removed them >>>>>>>>> => 13121 less nodes. >>>>>>>>> Remaining subnetworks:5 >>>>>>>>> The remaining subnetworks are: >>>>>>>>> subnetwork start from: >>>>>>>>> >>>>>>>>> 37.32611992939085,-121.9961998312816 >>>>>>>>> size: 24 >>>>>>>>> subnetwork start from: >>>>>>>>> >>>>>>>>> 37.56018439442332,-122.30257814308803 >>>>>>>>> size: 436637 >>>>>>>>> subnetwork start from: >>>>>>>>> >>>>>>>>> 37.78373608999855,-122.25065187925067 >>>>>>>>> size: 34 >>>>>>>>> subnetwork start from: >>>>>>>>> >>>>>>>>> 38.180185962770565,-121.70631393878864 >>>>>>>>> size: 301 >>>>>>>>> subnetwork start from: >>>>>>>>> >>>>>>>>> 37.85717050411933,-122.07633641532816 >>>>>>>>> size: 424 >>>>>>>>> >>>>>>>>> I don't understand why >>>>>>>>> there is still subnetwork >>>>>>>>> less than 200 nodes. >>>>>>>>> >>>>>>>>> I have a look >>>>>>>>> at >>>>>>>>> 37.32611992939085,-121.9961998312816. >>>>>>>>> It seesm related with >>>>>>>>> barrier=gate at intersection. >>>>>>>>> >>>>>>>>> http://www.openstreetmap.org/node/1126492194 >>>>>>>>> >>>>>>>>> *Best Regards,* >>>>>>>>> *ZhiQiang ZHAO* >>>>>>>>> >>>>>>>>> >>>>>> >>>>>> >
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