Changes between Version 87 and Version 88 of WKTRaster/SpecificationWorking03

Timestamp:

05/26/11 10:42:37 (2 years ago)

Author:

dustymugs

Comment:

ST_Sum

WKTRaster/SpecificationWorking03

@@ -1389 +1389 @@
 ----
 
+'''ST_Sum(raster, nband) -> double precision'''[[BR]]
+
+This function calls ST_SummaryStats and only returns the sum from that function.
+
+1. ST_Sum(rast raster, nband int, hasnodata boolean) -> double precision
+
+    returns the sum as an integer
+
+    nband: index of band
+
+    hasnodata: if FALSE, any pixel who's value is nodata is ignored
+
+{{{
+ST_Sum(rast, 1, FALSE)
+}}}
+
+2. ST_Sum(rast raster, nband int) -> double precision
+
+    assumes hasnodata = TRUE
+
+{{{
+ST_Sum(rast, 2)
+}}}
+
+3. ST_Sum(rast raster, hasnodata boolean) -> double precision
+
+    assumes nband = 1
+
+{{{
+ST_Sum(rast, TRUE)
+}}}
+
+4. ST_Sum(rast raster) -> double precision
+
+    assumes nband = 1 and hasnodata = TRUE
+
+{{{
+ST_Sum(rast)
+}}}
+
+The set of ST_ApproxSum functions are:
+
+1. ST_ApproxSum(rast raster, nband int, hasnodata boolean, sample_percent double precision) -> double precision
+
+    sample_percent: a value between 0 and 1 indicating the percentage of the raster band's pixels to consider
+
+{{{
+ST_ApproxSum(rast, 3, FALSE, 0.1)
+
+ST_ApproxSum(rast, 1, TRUE, 0.5)
+}}}
+
+2. ST_ApproxSum(rast raster, nband int, sample_percent double precision) -> double precision
+
+    assumes that nband = 1
+
+{{{
+ST_ApproxSum(rast, 2 0.01)
+
+ST_ApproxSum(rast, 4, 0.025)
+}}}
+
+3. ST_ApproxSum(rast raster, hasnodata boolean, sample_percent double precision) -> double precision
+
+    assumes that nband = 1
+
+{{{
+ST_ApproxSum(rast, FALSE, 0.01)
+
+ST_ApproxSum(rast, TRUE, 0.025)
+}}}
+
+4. ST_ApproxSum(rast raster, sample_percent double precision) -> double precision
+
+    assumes that nband = 1 and hasnodata = TRUE
+
+{{{
+ST_ApproxSum(rast, 0.25)
+}}}
+
+5. ST_ApproxSum(rast raster) -> double precision
+
+    assumes that nband = 1, hasnodata = TRUE and sample_percent = 0.1
+
+{{{
+ST_ApproxSum(rast)
+}}}
+
+The following functions are provided for coverage tables.
+
+1. ST_Sum(rastertable text, rastercolumn text, nband int, hasnodata boolean) -> double precision
+
+    rastertable: name of table with raster column
+
+    rastercolumn: name of column of data type raster
+
+{{{
+ST_Sum('tmax_2010', 'rast', 1, FALSE)
+
+ST_Sum('precip_2011', 'rast', 1, TRUE)
+}}}
+
+2. ST_Sum(rastertable text, rastercolumn text, nband int) -> double precision
+
+    hasnodata = TRUE
+
+{{{
+ST_Sum('tmax_2010', 'rast', 1)
+}}}
+
+3. ST_Sum(rastertable text, rastercolumn text, hasnodata boolean) -> double precision
+
+    nband = 1
+
+{{{
+ST_Sum('precip_2011', 'rast', TRUE)
+}}}
+
+4. ST_Sum(rastertable text, rastercolumn text) -> double precision
+
+    nband = 1 and hasnodata = TRUE
+
+{{{
+ST_Sum('tmin_2009', 'rast')
+}}}
+
+Variations for ST_ApproxSum are:
+
+1. ST_ApproxSum(rastertable text, rastercolumn text, nband int, hasnodata boolean, sample_percent double precision) -> double precision
+
+{{{
+ST_ApproxSum('tmax_2010', 'rast', 1, FALSE, 0.5)
+
+ST_ApproxSum('precip_2011', 'rast', 1, TRUE, 0.2)
+}}}
+
+2. ST_ApproxSum(rastertable text, rastercolumn text, nband int, sample_percent double precision) -> double precision
+
+    hasnodata = TRUE
+
+{{{
+ST_ApproxSum('tmax_2010', 'rast', 1, 0.5)
+
+ST_ApproxSum('precip_2011', 'rast', 1, 0.2)
+}}}
+
+3. ST_ApproxSum(rastertable text, rastercolumn text, hasnodata boolean, sample_percent double precision) -> double precision
+
+    nband = 1
+
+{{{
+ST_ApproxSum('tmax_2010', 'rast', FALSE, 0.5)
+
+ST_ApproxSum('precip_2011', 'rast', TRUE, 0.2)
+}}}
+
+4. ST_ApproxSum(rastertable text, rastercolumn text, sample_percent double precision) -> double precision
+
+    nband = 1 and hasnodata = TRUE
+
+{{{
+ST_ApproxSum('tmax_2010', 'rast', 0.5)
+
+ST_ApproxSum('precip_2011', 'rast', 0.2)
+}}}
+
+5. ST_ApproxSum(rastertable text, rastercolumn text) -> double precision
+
+    nband = 1, hasnodata = TRUE and sample_percent = 0.1
+
+{{{
+ST_ApproxSum('tmax_2010', 'rast')
+
+ST_ApproxSum('precip_2011', 'rast')
+}}}
+
+----
+
 '''ST_Mean(raster, nband) -> double precision'''[[BR]]
 This function calls ST_SummaryStats and only returns the mean from that function.