|
Action:
|
Negates an ordered graph.
|
|
|
Filename:
|
kern/kern_scm/graph_scm.cxx
|
|
|
Syntax:
|
(graph:negate in-graph)
|
|
|
Arg Types:
|
in-graph
|
graph
|
|
|
Returns:
|
graph
|
|
|
Description:
|
For noncyclic ordered graphs, the highest numbered vertices are assigned 0 and new numbering for the vertices commences from there. For cyclic ordered graphs, the 0 vertex remains the same, but sequence or direction around the cycle changes.
|
|
|
in-graph specifies a graph.
|
|
|
Example:
|
; graph:negate
|
|
; Create a simple graph.
|
|
(define g1 (graph "a-b b-c c-e c-d c-f f-g f-h"))
|
|
;; g1
|
|
(graph:order-from g1 "a")
|
|
;; 4
|
|
(graph:show-order g1)
|
|
;; ("a 0" "b 1" "c 2" "e 3" "d 3" "f 3" "g 4" "h 4")
|
|
(define g2 (graph:negate g1))
|
|
;; g2
|
|
(graph:show-order g2)
|
|
;; ("a 4" "b 3" "c 2" "e 1" "d 1" "f 1" "g 0" "h 0")
|
|
; Create a simple cyclic example
|
|
(define g3 (graph "me-you you-us us-them
|
|
|
them-they me-they"))
|
|
;; g3
|
|
; CAREFUL: The order of the graph output may
|
|
; not be the same each time.
|
|
(graph:cycle? g3)
|
|
;; #t
|
|
(graph:order-cyclic g3 "me" "you")
|
|
;; 4
|
|
(graph:show-order g3)
|
|
;; ("me 0" "you 4" "us 3" "them 2" "they 1")
|
|
(define g4 (graph:negate g3))
|
|
;; g4
|
|
(graph:show-order g4)
|
|
;; ("me 0" "you 1" "us 2" "them 3" "they 4")
|