[postgis-devel] [PostGIS] #930: [raster] ST_SummaryStats

[PostGIS]

#930: [raster] ST_SummaryStats
----------------------------+-----------------------------------------------
 Reporter:  dustymugs       |       Owner:  dustymugs            
     Type:  task            |      Status:  assigned             
 Priority:  medium          |   Milestone:  PostGIS Raster Future
Component:  postgis raster  |     Version:  trunk                
 Keywords:                  |  
----------------------------+-----------------------------------------------
Changes (by dustymugs):

  * status:  new => assigned


Comment:

 A set of ST_SummaryStats and ST_ApproxSummaryStats variations for
 processing coverages:

 1. ST_SummaryStats(rastertable text, rastercolumn text, nband int,
 hasnodata boolean) -> double precision

 {{{
 ST_SummaryStats('tmax_2010', 'rast', 1, FALSE)

 ST_SummaryStats('precip_2011', 'rast', 1, TRUE)
 }}}

 2. ST_SummaryStats(rastertable text, rastercolumn text, nband int) ->
 double precision

   hasnodata is set to FALSE

 {{{
 ST_SummaryStats('tmax_2010', 'rast', 1)
 }}}

 3. ST_SummaryStats(rastertable text, rastercolumn text, hasnodata boolean)
 -> double precision

   nband is set to 1

 {{{
 ST_SummaryStats('precip_2011', 'rast', TRUE)
 }}}

 4. ST_SummaryStats(rastertable text, rastercolumn text) -> double
 precision

   nband is set to 1 and hasnodata is set to FALSE

 {{{
 ST_SummaryStats('tmin_2009', 'rast')
 }}}

 Variations for ST_ApproxSummaryStats are:

 1. ST_ApproxSummaryStats(rastertable text, rastercolumn text, nband int,
 hasnodata boolean, sample_percent double precision) -> double precision

 {{{
 ST_ApproxSummaryStats('tmax_2010', 'rast', 1, FALSE, 0.5)

 ST_ApproxSummaryStats('precip_2011', 'rast', 1, TRUE, 0.2)
 }}}

 2. ST_ApproxSummaryStats(rastertable text, rastercolumn text, nband int,
 sample_percent double precision) -> double precision

   hasnodata is set to FALSE

 {{{
 ST_ApproxSummaryStats('tmax_2010', 'rast', 1, 0.5)

 ST_ApproxSummaryStats('precip_2011', 'rast', 1, 0.2)
 }}}

 3. ST_ApproxSummaryStats(rastertable text, rastercolumn text, hasnodata
 boolean, sample_percent double precision) -> double precision

   nband is set to 1

 {{{
 ST_ApproxSummaryStats('tmax_2010', 'rast', FALSE, 0.5)

 ST_ApproxSummaryStats('precip_2011', 'rast', TRUE, 0.2)
 }}}

 4. ST_ApproxSummaryStats(rastertable text, rastercolumn text,
 sample_percent double precision) -> double precision

   nband is set to 1 and hasnodata is set to FALSE

 {{{
 ST_ApproxSummaryStats('tmax_2010', 'rast', 0.5)

 ST_ApproxSummaryStats('precip_2011', 'rast', 0.2)
 }}}

 5. ST_ApproxSummaryStats(rastertable text, rastercolumn text) -> double
 precision

   nband is set to 1, hasnodata is set to FALSE and sample_percent is set
 to 0.1

 {{{
 ST_ApproxSummaryStats('tmax_2010', 'rast')

 ST_ApproxSummaryStats('precip_2011', 'rast')
 }}}

 The mean returned in these functions is a weighted mean of the means of
 each raster tile.  The standard deviation returned is the cumulative
 standard deviation of all raster tiles.

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/930#comment:3>
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