Changes between Version 13 and Version 14 of Grass7/TemporalGISAlgebra

Timestamp:

Jul 5, 2013, 8:38:16 AM (11 years ago)

Author:

huhabla

Comment:

--

Grass7/TemporalGISAlgebra

@@ -167 +167 @@
 
 The temporal raster algebra uses all operators and functions of the temporal 
-algebra and adds a subset of the operators and function of r.mapcalc.
+algebra and adds a subset of the arithmetic operators and function of r.mapcalc.
 
 The method is the same as for the temporal vector algebra. 
 Hence new spatio-temporal operators are defined that include temporal topology relations, 
-temporal operators and spatial operators.
-
+temporal operators and arithmetic operators.
 
 Examples:
@@ -179 +178 @@
 C = A + B
 }}}
-Same expression with explicit temporal topology and temporal interval processing operators. 
+Same expression with explicit definition of the temporal topology relation and temporal operators. 
 {{{
 C = A {equal,=+} B
 }}}
-Select all cells from STRDS B with equal relations to STRDS A if the cells of A are in the range of [100.0, 1600] of time intervals that have more then 30 days
-{{{
-C = if(equal, (A > 100 && A < 1600) {equal,&&} td(A) > 30, B)
-}}}
+Select all cells from STRDS B with equal relations to STRDS A if the cells 
+of A are in the range of [100.0, 1600] of time intervals that have more then 30 days
+{{{
+C = if(A > 100 && A < 1600 && td(A) > 30, B)
+
+same as:
+
+C = if(equal, A > 100 && A < 1600 {equal,&&} td(A) > 30, B)
+}}}
+Compute the recharge in meter per second for all maps of monthly precipitation STRDS "Prec" 
+if the monthly mean temperature specified in STRDS "Temp" is higher than 10 degrees. STRDS "Prec" and "Temp" have equal time stamps, the number of days per interval is computed using the td() function that has as argument the STRDS "Prec":
+{{{
+C = if(Temp > 10.0, Prec / 3600.0 /24.0 / td(Prec))
+
+same as:
+
+C = if(equal, Temp > 10.0, Prec / 3600.0 / 24.0 {equal,=/} td(Prec))
+}}}  
 
 All supported operators and functions are documented below.
-
 = Overview of all supported spatio-temporal operators and functions =