Good find Bborie! I would add that we should fill a ticket like "ST_Summary should report the x and y raster coordinates of the max and the min". So four new columns...
Pierre > -----Original Message----- > From: postgis-users-boun...@postgis.refractions.net [mailto:postgis-users- > boun...@postgis.refractions.net] On Behalf Of Bborie Park > Sent: Monday, June 25, 2012 4:32 PM > To: postgis-users@postgis.refractions.net > Subject: Re: [postgis-users] Finding highest cell value in raster using > ST_Value > > Egge-Jan, > > That is an intriguing question with no clean/simple solution. The > fastest approach may be to call ST_Reclass() to create a 1BB mask based > upon that value and the pass the resulting raster to > ST_PixelAsPolygons() which will give you what you want. > > Yes, the above is a round-about way to do this. This is something I'll > (ST_PixelofValue?) see about adding for PostGIS 2.1. > > -bborie > > On 06/25/2012 01:16 PM, e.j.h.polle wrote: > > Hi, > > > > OK - with ST_SummaryStats it is easy to retrieve the highest value in the > > raster, but then I only have this value. Now I want to retrieve > > (information about) the cell/pixel having this value, to be able to > > visualize the highest point on the map. My original query (see first post) > > does give me this information (after 45 seconds...). > > > > How would I go about to get hold of the pixel with the highest value, > > knowing this value? > > > > Cheers, > > > > Egge-Jan > > > > On Sunday, June 24, 2012 8:47:58 PM UTC+1, DavidRA wrote: > >> > >> Why don't you use ST_SummaryStats instead ST_Value? That way you can get > >> easily any basic stat, included the maximum value of the raster. It would > >> be > >> something like: > >> > >> SELECT (ST_SummaryStats(rast)).max FROM raster_table; > >> > >> -- > >> View this message in context: > >> http://postgis.17.n6.nabble.com/Finding-highest-cell-value-in-raster-using- > ST-Value-tp4998545p4998554.html > >> Sent from the PostGIS - User mailing list archive at Nabble.com. > >> _______________________________________________ > >> postgis-users mailing list > >> postgis-users@postgis.refractions.net > >> http://postgis.refractions.net/mailman/listinfo/postgis-users > >> > > > > On Sunday, June 24, 2012 8:47:58 PM UTC+1, DavidRA wrote: > >> > >> Why don't you use ST_SummaryStats instead ST_Value? That way you can get > >> easily any basic stat, included the maximum value of the raster. It would > >> be > >> something like: > >> > >> SELECT (ST_SummaryStats(rast)).max FROM raster_table; > >> > >> -- > >> View this message in context: > >> http://postgis.17.n6.nabble.com/Finding-highest-cell-value-in-raster-using- > ST-Value-tp4998545p4998554.html > >> Sent from the PostGIS - User mailing list archive at Nabble.com. > >> _______________________________________________ > >> postgis-users mailing list > >> postgis-users@postgis.refractions.net > >> http://postgis.refractions.net/mailman/listinfo/postgis-users > >> > > > > On Sunday, June 24, 2012 8:47:58 PM UTC+1, DavidRA wrote: > >> > >> Why don't you use ST_SummaryStats instead ST_Value? That way you can get > >> easily any basic stat, included the maximum value of the raster. It would > >> be > >> something like: > >> > >> SELECT (ST_SummaryStats(rast)).max FROM raster_table; > >> > >> -- > >> View this message in context: > >> http://postgis.17.n6.nabble.com/Finding-highest-cell-value-in-raster-using- > ST-Value-tp4998545p4998554.html > >> Sent from the PostGIS - User mailing list archive at Nabble.com. > >> _______________________________________________ > >> postgis-users mailing list > >> postgis-users@postgis.refractions.net > >> http://postgis.refractions.net/mailman/listinfo/postgis-users > >> > > > > > > > > _______________________________________________ > > postgis-users mailing list > > postgis-users@postgis.refractions.net > > http://postgis.refractions.net/mailman/listinfo/postgis-users > > -- > Bborie Park > Programmer > Center for Vectorborne Diseases > UC Davis > 530-752-8380 > bkp...@ucdavis.edu > _______________________________________________ > postgis-users mailing list > postgis-users@postgis.refractions.net > http://postgis.refractions.net/mailman/listinfo/postgis-users _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users