[pgrouting-users] Direction for path

[Stephen Woodbridge]

Here is the thread where I described it before:
http://www.google.com/#hl=en&num=100&newwindow=1&q=site%3Ahttp%3A%2F%2Flists.postlbs.org%2Fpipermail%2Fpgrouting-users%2F+swoodbridge+%22directions+problem%22&aq=f&aqi=&oq=&fp=2755c6b3e9b2e9

Also look at the GSoC project at:
http://sourceforge.net/apps/trac/opengraphrouter/wiki
http://imaptools.com:8080/maps/gsoc2009/?zoom=4&lat=53.56076&lon=-122.60619&layers=BTTT&start=-131.686064%2058.79915&stop=-114.055306%2049.024077&method=GetDD&lang=eng

This has an initial implementation is C++ but it is not well documented 
yet and needs a lot of additional work.

-Steve

poonam jalwan wrote:
> 
> Hi,
> 
> Can u explain me how u implement  direction of shortest path in 
> application.What is minimum requirement of data.
> 
> like my data structure is  :-
> 
> CREATE TABLE india_roads
> (
>  gid serial NOT NULL,
>  med_descri character varying(254),
>  rtt_descri character varying(254),
>  f_code_des character varying(10),
>  iso character varying(7),
>  isocountry character varying(54),
>  the_geom geometry,
>  source integer,
>  target integer,
>  length double precision,
>  "cost" double precision,
>  id integer NOT NULL DEFAULT nextval('india_roads_gid_seq'::regclass),
>  CONSTRAINT india_roads_pkey PRIMARY KEY (gid),
>  CONSTRAINT enforce_dims_the_geom CHECK (ndims(the_geom) = 2),
>  CONSTRAINT enforce_geotype_the_geom CHECK (geometrytype(the_geom) = 
> 'MULTILINESTRING'::text OR    the_geom IS NULL),
>  CONSTRAINT enforce_srid_the_geom CHECK (srid(the_geom) = 4326)
> )
> WITH (OIDS=FALSE);
> ALTER TABLE india_roads OWNER TO postgres;
> GRANT ALL ON TABLE india_roads TO postgres;
> GRANT SELECT ON TABLE india_roads TO public;
> 
> Finding direction of shortest path is possible on my dataset..
> 
> 
> 
> Thanks
> Poonam
> 
> Stephen Woodbridge wrote:
>> poonam jalwan wrote:
>>> Hi All,
>>>
>>> I am using pgrouting functions for finding  shortest path from point 
>>> A to point B,Now i want to find the direction of shortest path and 
>>> multiple path from point A to point B.Please anyone help which 
>>> function of pgrouting i have to use.
>>
>> When you say "direction of shortest path" are you referring to human 
>> readable text driving directions?
>>
>> If so there currently is no function in pgRouting that does that. I 
>> have discussed this in some detail on the list (check the archives), 
>> and how it can be implemented. I have implemented this:
>> http://imaptools.com:8080/maps/dd2.html?lat=34.53886&lon=69.15786&zoom=13&layers=B00TFTTTF&start=69.144741%2034.547085&stop=69.172264%2034.531735&method=STS&lang=eng 
>>
>> but is dependent on the structure of the data tables you load and use. 
>> There is a lot more information in the archives explain how this was 
>> done.
>>
>> -Steve
>>
> 
> 
> 
>