Changes between Version 7 and Version 8 of Grass7/TemporalGISAlgebra

Timestamp:

Jul 5, 2013, 6:22:58 AM (11 years ago)

Author:

huhabla

Comment:

--

Grass7/TemporalGISAlgebra

@@ -84 +84 @@
 Temporally shift all maps of space time dataset A by two months.
 
-==== Temporally snap ===
+==== Temporally snap ====
 
 Temporally snap time instances to its temporal nearest neighbor in the future and close gaps between time intervals.
@@ -266 +266 @@
    C = A : B
    C = A {:} B
-   C = A {=:} B
    C = A {equals,:} B
-   C = A {equals,=:} B
 }}}
 
@@ -278 +276 @@
    C = A !: B
    C = A {!:} B
-   C = A {=!:} B
    C = A {equals,!:} B
-   C = A {equals,=!:} B
 }}}
 
  * Select all maps from space time dataset A that 
    are during time intervals of space time dataset B
-   and store them in space time datasets C. Use
-   the time interval/instances of A in C.
+   and store them in space time datasets C. 
   
 {{{
    C = A {during,:} B
-   C = A {during,=:} B
-}}}
-
- * Select all maps from space time dataset A that 
-   are during time intervals of space time dataset B
-   and store them in space time datasets C. The maps
-   in C will have different time intervals as A or B using the union operator.
-   Hence they are unions between time intervals of A and B.
-  
-{{{
-   C = A {during,|:} B
 }}}
 
  * Select all maps from space time dataset A
    that are during B and during C and during D.
-   Store the resulting list of maps using the timer intervals/instances
-   of A in E.
-
-{{{
-   E = A {during,=:} B {during,=:} C {during,=:} D
+
+{{{
+   E = A {during,:} B {during,:} C {during,:} D
 }}}
 
@@ -324 +306 @@
 
 
-== Combination of temporal operators ==
-
-{{{
- --------------
-|   |  : |  !: |
-|---|- --|-----|
-| & | &: | &!: |
-| | | |: | |!: |
-| + | +: | +!: |
-| = | =: | =!: |
- --------------
-}}}
-
-
 == Logical operators ==
 
-{{{
-==    equal  
-!=    not equal  
->     greater than
->=    greater than or equal
-<     less than
-<=    less than or equal
-&&    and
-||    or
-
+
+Logical operators:
+
+{{{
+Symbol  description             precedence
+
+  ==    equal                   3
+  !=    not equal               3
+  >     greater than            3
+  >=    greater than or equal   3
+  <     less than               3
+  <=    less than or equal      3
+  &&    and                     4
+  ||    or                      4
+}}}
+
+Combination of temporal and logical operators:
+
+{{{
+ -------------------------------------------------
+|   |  && |  || |  == |  != |  <= |  >= |  < |  > |
+|---|-----|-----|-----|-----|-----|-----|----|----|
+| & | &&& | &|| | &== | &!= | &<= | &>= | &< | &> |
+| | | |&& | ||| | |== | |!= | |<= | |>= | |< | |> |
+| + | +&& | +|| | +== | +!= | +<= | +>= | +< | +> |
+| = | =&& | =|| | === | =!= | =<= | =>= | =< | => |
+ -------------------------------------------- ----
 }}}
 
@@ -358 +343 @@
 {{{
 if                      decision option
-  if(x, a)              a if x not 0
-  if(x, a, b)           a if x not 0, b otherwise
+  if(if, then, else)
+  if(x, a)              a if x not 0; temporal topological relation between if and then is equal
+  if(x, a, b)           a if x not 0, b otherwise; temporal topological relation between if, then and else is equal
+  if(topo, x, a)        a if x not 0; temporal topological relation between if and then is explicit specified by topo
+  if(topo, x, a, b)     a if x not 0, b otherwise; temporal topological relation between if, then and else is explicit specified by topo
 
 buff_t(a, size)         Buffer stds a with granule ("1 month" or 5)
 tshift(a, size)         Shift stds a with granule ("1 month" or 5)
 tsnap(a)                Snap time instances and intervals of stds a
+
+td(a)                   Returns a list of time intervals of stds a
 
 start_time()            Start time as HH::MM:SS
@@ -469 +459 @@
   +     addition        2
   -     subtraction     2
-}}}
-
-Logical operators:
-
-{{{
-Symbol  description             precedence
-
-  ==    equal                   3
-  !=    not equal               3
-  >     greater than            3
-  >=    greater than or equal   3
-  <     less than               3
-  <=    less than or equal      3
-  &&    and                     4
-  ||    or                      4
 }}}
 
@@ -539 +514 @@
  ---------------------------------------
 }}}
-
-Combination of temporal and logical raster operators:
-
-{{{
- ------------------------------------------------
-|   |  : |  !: |  == |  != |  <= |  >= |  < |  > |
-|---|----|-----|-----|-----|-----|-----|----|----|
-| & | &: | &!: | &== | &!= | &<= | &>= | &< | &> |
-| | | |: | |!: | |== | |!= | |<= | |>= | |< | |> |
-| + | +: | +!: | +== | +!= | +<= | +>= | +< | +> |
-| = | =: | =!: | === | =!= | =<= | =>= | =< | => |
- ------------------------------------------- ----
-}}}
-
-Note the combination of temporal and logical operators is only
-possible in reference time mode.
-