[GraphHopper] There must be bug on the subnetwork removal
Peter
graphhopper at gmx.de
Tue Jul 28 07:02:31 UTC 2015
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 <graphhopper at gmx.de
> <mailto:graphhopper at gmx.de>> 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 <graphhopper at gmx.de
>> <mailto:graphhopper at gmx.de>> 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 <graphhopper at gmx.de
>>> <mailto:graphhopper at gmx.de>> 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
>>>> <graphhopper at gmx.de <mailto:graphhopper at gmx.de>> 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
>>>>> <johnthu at gmail.com <mailto:johnthu at gmail.com>> 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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