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Posted to solr-user@lucene.apache.org by Jamie Johnson <je...@gmail.com> on 2012/06/10 19:49:29 UTC
Building a heat map from geo data in index
I had a request from a customer which to this point I have not seen
much similar so I figured I'd pose the question here. I've been asked
if it was possible to build a heat map from the results of a query. I
can imagine a process to do this through some post processing, but
that sounds very expensive for large/distributed indices so I was
wondering if with all of the new geospatial support that is being
added to lucene/solr there was a way to do geospatial faceting. What
I am imagining is bounding box being defined and that box being broken
into an N by N matrix, each of which would return counts so a heat map
could be constructed. Any other thoughts on this would be greatly
appreciated, right now I am really just fishing for some ideas.
Re: Building a heat map from geo data in index
Posted by Jamie Johnson <je...@gmail.com>.
So I've tried this a bit, but I can't get it to look quite right.
What I was doing up until now was taking the center point of the
geohash cell as location for the value I am getting from the index.
Doing this you end up with what appears to be islands (using
HeatMap.js currently). I guess what I would like to do is take this
information and generate a static image so I can quickly prototype
some things. Are there any good Java based heatmap tools? Also if
anyone has done this before any thoughts on how to do this would
really be appreciated.
On Mon, Jun 11, 2012 at 12:52 PM, Jamie Johnson <je...@gmail.com> wrote:
> Yeah I'll have to play to see how useful it is, I really don't know at
> this point.
>
> On another note we already using some binning like is described in teh
> wiki you sent, specifically http://code.google.com/p/javageomodel/ for
> other purposes. Not sure if that could be used or not, guess I'd have
> to think on it harder.
>
>
> On Mon, Jun 11, 2012 at 12:04 PM, Tanguy Moal <ta...@gmail.com> wrote:
>> Yes it looks interesting and is not too difficult to do.
>> However, the length of the geohashes gives you very little control on the
>> size of the regions to colorize. Quoting wikipedia :
>> geohash length
>>
>>
>> km error1
>>
>>
>>
>> ±25002
>>
>>
>>
>> ±6303
>>
>>
>>
>> ±784
>>
>>
>> ±205
>>
>>
>> ±2.46
>>
>>
>>
>> ±0.617
>>
>>
>>
>> ±0.0768
>>
>>
>>
>> ±0.019
>> This is interesting also : http://wiki.openstreetmap.org/wiki/QuadTiles
>> But it does what you're looking for, somehow :)
>>
>> --
>> Tanguy
>>
>>
>> 2012/6/11 Jamie Johnson <je...@gmail.com>
>>
>>> If you look at the Stack response from David he had suggested breaking
>>> the geohash up into pieces and then using a prefix for refining
>>> precision. I hadn't imagined limiting this to a particular area, just
>>> limiting it based on the prefix (which would be based on users zoom
>>> level or something) allowing the information to become more precise as
>>> the user zoomed in. That seemed a very reasonable approach to the
>>> problem.
>>>
>>> On Mon, Jun 11, 2012 at 10:55 AM, Tanguy Moal <ta...@gmail.com>
>>> wrote:
>>> > There is definitely something interesting to do around geohashes.
>>> >
>>> > I'm wondering how one could map the N by N tiles requested tiles to a
>>> range
>>> > of geohashes. (Where the gap would be a function of N).
>>> > What I try to mean is that I don't know if a bijective function exist
>>> > between tiles and geohash ranges.
>>> > I don't even know if a contiguous range of geohashes ends up in a squared
>>> > box.
>>> >
>>> > Because if you can find such a function, then you could probably solve
>>> the
>>> > issue by asking facet ranges on a geohash field to solr.
>>> >
>>> > I don't if that helps but the topic is very interesting to me...
>>> > Please share your findings, if any :-)
>>> >
>>> > --
>>> > Tanguy
>>> >
>>> > 2012/6/11 Dmitry Kan <dm...@gmail.com>
>>> >
>>> >> so it sounds to me, that the geohash is just a hash representation of
>>> lat,
>>> >> lon coordinates for an easier referencing (see e.g.
>>> >> http://en.wikipedia.org/wiki/Geohash).
>>> >> I would probably start with something easier, having bbox lat,lon
>>> >> coordinate pairs of top left corner (or in some coordinate systems, it
>>> is
>>> >> down left corner), break each bbox into cells of size w/N, h/N (and
>>> >> probably, that's equal numbers). Then you can loop over the cells and
>>> >> compute your facet counts with bbox of a cell. You could then evolve
>>> this
>>> >> to geohashes, if you want, but at least you would know where to start.
>>> >>
>>> >> -- Dmitry
>>> >>
>>> >> On Mon, Jun 11, 2012 at 4:48 PM, Jamie Johnson <je...@gmail.com>
>>> wrote:
>>> >>
>>> >> > That is certainly an option but the collecting of the heat map data is
>>> >> > really the question.
>>> >> >
>>> >> > I saw this
>>> >> >
>>> >> >
>>> >> >
>>> >>
>>> http://stackoverflow.com/questions/8798711/solr-using-facets-to-sum-documents-based-on-variable-precision-geohashes
>>> >> >
>>> >> > but don't have a really good understanding of how this would be
>>> >> > accomplished. I need to get a more firm understanding of geohashes as
>>> >> > my understanding is extremely lacking at this point.
>>> >> >
>>> >> > On Mon, Jun 11, 2012 at 8:55 AM, Stefan Matheis
>>> >> > <ma...@googlemail.com> wrote:
>>> >> > > I'm not entirely sure, that it has to be that complicated .. what
>>> about
>>> >> > using for example http://www.patrick-wied.at/static/heatmapjs/ ? You
>>> >> > could collect all the geo-related data and do the (heat)map stuff on
>>> the
>>> >> > client.
>>> >> > >
>>> >> > >
>>> >> > >
>>> >> > > On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
>>> >> > >
>>> >> > >> I had a request from a customer which to this point I have not seen
>>> >> > >> much similar so I figured I'd pose the question here. I've been
>>> asked
>>> >> > >> if it was possible to build a heat map from the results of a
>>> query. I
>>> >> > >> can imagine a process to do this through some post processing, but
>>> >> > >> that sounds very expensive for large/distributed indices so I was
>>> >> > >> wondering if with all of the new geospatial support that is being
>>> >> > >> added to lucene/solr there was a way to do geospatial faceting.
>>> What
>>> >> > >> I am imagining is bounding box being defined and that box being
>>> broken
>>> >> > >> into an N by N matrix, each of which would return counts so a heat
>>> map
>>> >> > >> could be constructed. Any other thoughts on this would be greatly
>>> >> > >> appreciated, right now I am really just fishing for some ideas.
>>> >> > >
>>> >> > >
>>> >> > >
>>> >> >
>>> >>
>>> >>
>>> >>
>>> >> --
>>> >> Regards,
>>> >>
>>> >> Dmitry Kan
>>> >>
>>>
Re: Building a heat map from geo data in index
Posted by Jamie Johnson <je...@gmail.com>.
Yeah I'll have to play to see how useful it is, I really don't know at
this point.
On another note we already using some binning like is described in teh
wiki you sent, specifically http://code.google.com/p/javageomodel/ for
other purposes. Not sure if that could be used or not, guess I'd have
to think on it harder.
On Mon, Jun 11, 2012 at 12:04 PM, Tanguy Moal <ta...@gmail.com> wrote:
> Yes it looks interesting and is not too difficult to do.
> However, the length of the geohashes gives you very little control on the
> size of the regions to colorize. Quoting wikipedia :
> geohash length
>
>
> km error1
>
>
>
> ±25002
>
>
>
> ±6303
>
>
>
> ±784
>
>
> ±205
>
>
> ±2.46
>
>
>
> ±0.617
>
>
>
> ±0.0768
>
>
>
> ±0.019
> This is interesting also : http://wiki.openstreetmap.org/wiki/QuadTiles
> But it does what you're looking for, somehow :)
>
> --
> Tanguy
>
>
> 2012/6/11 Jamie Johnson <je...@gmail.com>
>
>> If you look at the Stack response from David he had suggested breaking
>> the geohash up into pieces and then using a prefix for refining
>> precision. I hadn't imagined limiting this to a particular area, just
>> limiting it based on the prefix (which would be based on users zoom
>> level or something) allowing the information to become more precise as
>> the user zoomed in. That seemed a very reasonable approach to the
>> problem.
>>
>> On Mon, Jun 11, 2012 at 10:55 AM, Tanguy Moal <ta...@gmail.com>
>> wrote:
>> > There is definitely something interesting to do around geohashes.
>> >
>> > I'm wondering how one could map the N by N tiles requested tiles to a
>> range
>> > of geohashes. (Where the gap would be a function of N).
>> > What I try to mean is that I don't know if a bijective function exist
>> > between tiles and geohash ranges.
>> > I don't even know if a contiguous range of geohashes ends up in a squared
>> > box.
>> >
>> > Because if you can find such a function, then you could probably solve
>> the
>> > issue by asking facet ranges on a geohash field to solr.
>> >
>> > I don't if that helps but the topic is very interesting to me...
>> > Please share your findings, if any :-)
>> >
>> > --
>> > Tanguy
>> >
>> > 2012/6/11 Dmitry Kan <dm...@gmail.com>
>> >
>> >> so it sounds to me, that the geohash is just a hash representation of
>> lat,
>> >> lon coordinates for an easier referencing (see e.g.
>> >> http://en.wikipedia.org/wiki/Geohash).
>> >> I would probably start with something easier, having bbox lat,lon
>> >> coordinate pairs of top left corner (or in some coordinate systems, it
>> is
>> >> down left corner), break each bbox into cells of size w/N, h/N (and
>> >> probably, that's equal numbers). Then you can loop over the cells and
>> >> compute your facet counts with bbox of a cell. You could then evolve
>> this
>> >> to geohashes, if you want, but at least you would know where to start.
>> >>
>> >> -- Dmitry
>> >>
>> >> On Mon, Jun 11, 2012 at 4:48 PM, Jamie Johnson <je...@gmail.com>
>> wrote:
>> >>
>> >> > That is certainly an option but the collecting of the heat map data is
>> >> > really the question.
>> >> >
>> >> > I saw this
>> >> >
>> >> >
>> >> >
>> >>
>> http://stackoverflow.com/questions/8798711/solr-using-facets-to-sum-documents-based-on-variable-precision-geohashes
>> >> >
>> >> > but don't have a really good understanding of how this would be
>> >> > accomplished. I need to get a more firm understanding of geohashes as
>> >> > my understanding is extremely lacking at this point.
>> >> >
>> >> > On Mon, Jun 11, 2012 at 8:55 AM, Stefan Matheis
>> >> > <ma...@googlemail.com> wrote:
>> >> > > I'm not entirely sure, that it has to be that complicated .. what
>> about
>> >> > using for example http://www.patrick-wied.at/static/heatmapjs/ ? You
>> >> > could collect all the geo-related data and do the (heat)map stuff on
>> the
>> >> > client.
>> >> > >
>> >> > >
>> >> > >
>> >> > > On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
>> >> > >
>> >> > >> I had a request from a customer which to this point I have not seen
>> >> > >> much similar so I figured I'd pose the question here. I've been
>> asked
>> >> > >> if it was possible to build a heat map from the results of a
>> query. I
>> >> > >> can imagine a process to do this through some post processing, but
>> >> > >> that sounds very expensive for large/distributed indices so I was
>> >> > >> wondering if with all of the new geospatial support that is being
>> >> > >> added to lucene/solr there was a way to do geospatial faceting.
>> What
>> >> > >> I am imagining is bounding box being defined and that box being
>> broken
>> >> > >> into an N by N matrix, each of which would return counts so a heat
>> map
>> >> > >> could be constructed. Any other thoughts on this would be greatly
>> >> > >> appreciated, right now I am really just fishing for some ideas.
>> >> > >
>> >> > >
>> >> > >
>> >> >
>> >>
>> >>
>> >>
>> >> --
>> >> Regards,
>> >>
>> >> Dmitry Kan
>> >>
>>
Re: Building a heat map from geo data in index
Posted by Tanguy Moal <ta...@gmail.com>.
Yes it looks interesting and is not too difficult to do.
However, the length of the geohashes gives you very little control on the
size of the regions to colorize. Quoting wikipedia :
geohash length
km error1
±25002
±6303
±784
±205
±2.46
±0.617
±0.0768
±0.019
This is interesting also : http://wiki.openstreetmap.org/wiki/QuadTiles
But it does what you're looking for, somehow :)
--
Tanguy
2012/6/11 Jamie Johnson <je...@gmail.com>
> If you look at the Stack response from David he had suggested breaking
> the geohash up into pieces and then using a prefix for refining
> precision. I hadn't imagined limiting this to a particular area, just
> limiting it based on the prefix (which would be based on users zoom
> level or something) allowing the information to become more precise as
> the user zoomed in. That seemed a very reasonable approach to the
> problem.
>
> On Mon, Jun 11, 2012 at 10:55 AM, Tanguy Moal <ta...@gmail.com>
> wrote:
> > There is definitely something interesting to do around geohashes.
> >
> > I'm wondering how one could map the N by N tiles requested tiles to a
> range
> > of geohashes. (Where the gap would be a function of N).
> > What I try to mean is that I don't know if a bijective function exist
> > between tiles and geohash ranges.
> > I don't even know if a contiguous range of geohashes ends up in a squared
> > box.
> >
> > Because if you can find such a function, then you could probably solve
> the
> > issue by asking facet ranges on a geohash field to solr.
> >
> > I don't if that helps but the topic is very interesting to me...
> > Please share your findings, if any :-)
> >
> > --
> > Tanguy
> >
> > 2012/6/11 Dmitry Kan <dm...@gmail.com>
> >
> >> so it sounds to me, that the geohash is just a hash representation of
> lat,
> >> lon coordinates for an easier referencing (see e.g.
> >> http://en.wikipedia.org/wiki/Geohash).
> >> I would probably start with something easier, having bbox lat,lon
> >> coordinate pairs of top left corner (or in some coordinate systems, it
> is
> >> down left corner), break each bbox into cells of size w/N, h/N (and
> >> probably, that's equal numbers). Then you can loop over the cells and
> >> compute your facet counts with bbox of a cell. You could then evolve
> this
> >> to geohashes, if you want, but at least you would know where to start.
> >>
> >> -- Dmitry
> >>
> >> On Mon, Jun 11, 2012 at 4:48 PM, Jamie Johnson <je...@gmail.com>
> wrote:
> >>
> >> > That is certainly an option but the collecting of the heat map data is
> >> > really the question.
> >> >
> >> > I saw this
> >> >
> >> >
> >> >
> >>
> http://stackoverflow.com/questions/8798711/solr-using-facets-to-sum-documents-based-on-variable-precision-geohashes
> >> >
> >> > but don't have a really good understanding of how this would be
> >> > accomplished. I need to get a more firm understanding of geohashes as
> >> > my understanding is extremely lacking at this point.
> >> >
> >> > On Mon, Jun 11, 2012 at 8:55 AM, Stefan Matheis
> >> > <ma...@googlemail.com> wrote:
> >> > > I'm not entirely sure, that it has to be that complicated .. what
> about
> >> > using for example http://www.patrick-wied.at/static/heatmapjs/ ? You
> >> > could collect all the geo-related data and do the (heat)map stuff on
> the
> >> > client.
> >> > >
> >> > >
> >> > >
> >> > > On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
> >> > >
> >> > >> I had a request from a customer which to this point I have not seen
> >> > >> much similar so I figured I'd pose the question here. I've been
> asked
> >> > >> if it was possible to build a heat map from the results of a
> query. I
> >> > >> can imagine a process to do this through some post processing, but
> >> > >> that sounds very expensive for large/distributed indices so I was
> >> > >> wondering if with all of the new geospatial support that is being
> >> > >> added to lucene/solr there was a way to do geospatial faceting.
> What
> >> > >> I am imagining is bounding box being defined and that box being
> broken
> >> > >> into an N by N matrix, each of which would return counts so a heat
> map
> >> > >> could be constructed. Any other thoughts on this would be greatly
> >> > >> appreciated, right now I am really just fishing for some ideas.
> >> > >
> >> > >
> >> > >
> >> >
> >>
> >>
> >>
> >> --
> >> Regards,
> >>
> >> Dmitry Kan
> >>
>
Re: Building a heat map from geo data in index
Posted by Jamie Johnson <je...@gmail.com>.
If you look at the Stack response from David he had suggested breaking
the geohash up into pieces and then using a prefix for refining
precision. I hadn't imagined limiting this to a particular area, just
limiting it based on the prefix (which would be based on users zoom
level or something) allowing the information to become more precise as
the user zoomed in. That seemed a very reasonable approach to the
problem.
On Mon, Jun 11, 2012 at 10:55 AM, Tanguy Moal <ta...@gmail.com> wrote:
> There is definitely something interesting to do around geohashes.
>
> I'm wondering how one could map the N by N tiles requested tiles to a range
> of geohashes. (Where the gap would be a function of N).
> What I try to mean is that I don't know if a bijective function exist
> between tiles and geohash ranges.
> I don't even know if a contiguous range of geohashes ends up in a squared
> box.
>
> Because if you can find such a function, then you could probably solve the
> issue by asking facet ranges on a geohash field to solr.
>
> I don't if that helps but the topic is very interesting to me...
> Please share your findings, if any :-)
>
> --
> Tanguy
>
> 2012/6/11 Dmitry Kan <dm...@gmail.com>
>
>> so it sounds to me, that the geohash is just a hash representation of lat,
>> lon coordinates for an easier referencing (see e.g.
>> http://en.wikipedia.org/wiki/Geohash).
>> I would probably start with something easier, having bbox lat,lon
>> coordinate pairs of top left corner (or in some coordinate systems, it is
>> down left corner), break each bbox into cells of size w/N, h/N (and
>> probably, that's equal numbers). Then you can loop over the cells and
>> compute your facet counts with bbox of a cell. You could then evolve this
>> to geohashes, if you want, but at least you would know where to start.
>>
>> -- Dmitry
>>
>> On Mon, Jun 11, 2012 at 4:48 PM, Jamie Johnson <je...@gmail.com> wrote:
>>
>> > That is certainly an option but the collecting of the heat map data is
>> > really the question.
>> >
>> > I saw this
>> >
>> >
>> >
>> http://stackoverflow.com/questions/8798711/solr-using-facets-to-sum-documents-based-on-variable-precision-geohashes
>> >
>> > but don't have a really good understanding of how this would be
>> > accomplished. I need to get a more firm understanding of geohashes as
>> > my understanding is extremely lacking at this point.
>> >
>> > On Mon, Jun 11, 2012 at 8:55 AM, Stefan Matheis
>> > <ma...@googlemail.com> wrote:
>> > > I'm not entirely sure, that it has to be that complicated .. what about
>> > using for example http://www.patrick-wied.at/static/heatmapjs/ ? You
>> > could collect all the geo-related data and do the (heat)map stuff on the
>> > client.
>> > >
>> > >
>> > >
>> > > On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
>> > >
>> > >> I had a request from a customer which to this point I have not seen
>> > >> much similar so I figured I'd pose the question here. I've been asked
>> > >> if it was possible to build a heat map from the results of a query. I
>> > >> can imagine a process to do this through some post processing, but
>> > >> that sounds very expensive for large/distributed indices so I was
>> > >> wondering if with all of the new geospatial support that is being
>> > >> added to lucene/solr there was a way to do geospatial faceting. What
>> > >> I am imagining is bounding box being defined and that box being broken
>> > >> into an N by N matrix, each of which would return counts so a heat map
>> > >> could be constructed. Any other thoughts on this would be greatly
>> > >> appreciated, right now I am really just fishing for some ideas.
>> > >
>> > >
>> > >
>> >
>>
>>
>>
>> --
>> Regards,
>>
>> Dmitry Kan
>>
Re: Building a heat map from geo data in index
Posted by Tanguy Moal <ta...@gmail.com>.
There is definitely something interesting to do around geohashes.
I'm wondering how one could map the N by N tiles requested tiles to a range
of geohashes. (Where the gap would be a function of N).
What I try to mean is that I don't know if a bijective function exist
between tiles and geohash ranges.
I don't even know if a contiguous range of geohashes ends up in a squared
box.
Because if you can find such a function, then you could probably solve the
issue by asking facet ranges on a geohash field to solr.
I don't if that helps but the topic is very interesting to me...
Please share your findings, if any :-)
--
Tanguy
2012/6/11 Dmitry Kan <dm...@gmail.com>
> so it sounds to me, that the geohash is just a hash representation of lat,
> lon coordinates for an easier referencing (see e.g.
> http://en.wikipedia.org/wiki/Geohash).
> I would probably start with something easier, having bbox lat,lon
> coordinate pairs of top left corner (or in some coordinate systems, it is
> down left corner), break each bbox into cells of size w/N, h/N (and
> probably, that's equal numbers). Then you can loop over the cells and
> compute your facet counts with bbox of a cell. You could then evolve this
> to geohashes, if you want, but at least you would know where to start.
>
> -- Dmitry
>
> On Mon, Jun 11, 2012 at 4:48 PM, Jamie Johnson <je...@gmail.com> wrote:
>
> > That is certainly an option but the collecting of the heat map data is
> > really the question.
> >
> > I saw this
> >
> >
> >
> http://stackoverflow.com/questions/8798711/solr-using-facets-to-sum-documents-based-on-variable-precision-geohashes
> >
> > but don't have a really good understanding of how this would be
> > accomplished. I need to get a more firm understanding of geohashes as
> > my understanding is extremely lacking at this point.
> >
> > On Mon, Jun 11, 2012 at 8:55 AM, Stefan Matheis
> > <ma...@googlemail.com> wrote:
> > > I'm not entirely sure, that it has to be that complicated .. what about
> > using for example http://www.patrick-wied.at/static/heatmapjs/ ? You
> > could collect all the geo-related data and do the (heat)map stuff on the
> > client.
> > >
> > >
> > >
> > > On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
> > >
> > >> I had a request from a customer which to this point I have not seen
> > >> much similar so I figured I'd pose the question here. I've been asked
> > >> if it was possible to build a heat map from the results of a query. I
> > >> can imagine a process to do this through some post processing, but
> > >> that sounds very expensive for large/distributed indices so I was
> > >> wondering if with all of the new geospatial support that is being
> > >> added to lucene/solr there was a way to do geospatial faceting. What
> > >> I am imagining is bounding box being defined and that box being broken
> > >> into an N by N matrix, each of which would return counts so a heat map
> > >> could be constructed. Any other thoughts on this would be greatly
> > >> appreciated, right now I am really just fishing for some ideas.
> > >
> > >
> > >
> >
>
>
>
> --
> Regards,
>
> Dmitry Kan
>
Re: Building a heat map from geo data in index
Posted by Dmitry Kan <dm...@gmail.com>.
so it sounds to me, that the geohash is just a hash representation of lat,
lon coordinates for an easier referencing (see e.g.
http://en.wikipedia.org/wiki/Geohash).
I would probably start with something easier, having bbox lat,lon
coordinate pairs of top left corner (or in some coordinate systems, it is
down left corner), break each bbox into cells of size w/N, h/N (and
probably, that's equal numbers). Then you can loop over the cells and
compute your facet counts with bbox of a cell. You could then evolve this
to geohashes, if you want, but at least you would know where to start.
-- Dmitry
On Mon, Jun 11, 2012 at 4:48 PM, Jamie Johnson <je...@gmail.com> wrote:
> That is certainly an option but the collecting of the heat map data is
> really the question.
>
> I saw this
>
>
> http://stackoverflow.com/questions/8798711/solr-using-facets-to-sum-documents-based-on-variable-precision-geohashes
>
> but don't have a really good understanding of how this would be
> accomplished. I need to get a more firm understanding of geohashes as
> my understanding is extremely lacking at this point.
>
> On Mon, Jun 11, 2012 at 8:55 AM, Stefan Matheis
> <ma...@googlemail.com> wrote:
> > I'm not entirely sure, that it has to be that complicated .. what about
> using for example http://www.patrick-wied.at/static/heatmapjs/ ? You
> could collect all the geo-related data and do the (heat)map stuff on the
> client.
> >
> >
> >
> > On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
> >
> >> I had a request from a customer which to this point I have not seen
> >> much similar so I figured I'd pose the question here. I've been asked
> >> if it was possible to build a heat map from the results of a query. I
> >> can imagine a process to do this through some post processing, but
> >> that sounds very expensive for large/distributed indices so I was
> >> wondering if with all of the new geospatial support that is being
> >> added to lucene/solr there was a way to do geospatial faceting. What
> >> I am imagining is bounding box being defined and that box being broken
> >> into an N by N matrix, each of which would return counts so a heat map
> >> could be constructed. Any other thoughts on this would be greatly
> >> appreciated, right now I am really just fishing for some ideas.
> >
> >
> >
>
--
Regards,
Dmitry Kan
Re: Building a heat map from geo data in index
Posted by Jamie Johnson <je...@gmail.com>.
That is certainly an option but the collecting of the heat map data is
really the question.
I saw this
http://stackoverflow.com/questions/8798711/solr-using-facets-to-sum-documents-based-on-variable-precision-geohashes
but don't have a really good understanding of how this would be
accomplished. I need to get a more firm understanding of geohashes as
my understanding is extremely lacking at this point.
On Mon, Jun 11, 2012 at 8:55 AM, Stefan Matheis
<ma...@googlemail.com> wrote:
> I'm not entirely sure, that it has to be that complicated .. what about using for example http://www.patrick-wied.at/static/heatmapjs/ ? You could collect all the geo-related data and do the (heat)map stuff on the client.
>
>
>
> On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
>
>> I had a request from a customer which to this point I have not seen
>> much similar so I figured I'd pose the question here. I've been asked
>> if it was possible to build a heat map from the results of a query. I
>> can imagine a process to do this through some post processing, but
>> that sounds very expensive for large/distributed indices so I was
>> wondering if with all of the new geospatial support that is being
>> added to lucene/solr there was a way to do geospatial faceting. What
>> I am imagining is bounding box being defined and that box being broken
>> into an N by N matrix, each of which would return counts so a heat map
>> could be constructed. Any other thoughts on this would be greatly
>> appreciated, right now I am really just fishing for some ideas.
>
>
>
Re: Building a heat map from geo data in index
Posted by Stefan Matheis <ma...@googlemail.com>.
I'm not entirely sure, that it has to be that complicated .. what about using for example http://www.patrick-wied.at/static/heatmapjs/ ? You could collect all the geo-related data and do the (heat)map stuff on the client.
On Sunday, June 10, 2012 at 7:49 PM, Jamie Johnson wrote:
> I had a request from a customer which to this point I have not seen
> much similar so I figured I'd pose the question here. I've been asked
> if it was possible to build a heat map from the results of a query. I
> can imagine a process to do this through some post processing, but
> that sounds very expensive for large/distributed indices so I was
> wondering if with all of the new geospatial support that is being
> added to lucene/solr there was a way to do geospatial faceting. What
> I am imagining is bounding box being defined and that box being broken
> into an N by N matrix, each of which would return counts so a heat map
> could be constructed. Any other thoughts on this would be greatly
> appreciated, right now I am really just fishing for some ideas.