|
|
新手,在看netlogo自带的例子时,有几行程序看不懂,希望高手能够指点。( K$ x7 N$ ^* E9 { s/ ], q. c/ q
netlogo自带的social science--traffic grid这一例子当中,1 f3 w+ A9 H' H7 X1 s3 i
globals
3 k8 f8 S$ K$ h/ T( p/ c7 u[
- f) v: |% M( Z* W; |+ m) z grid-x-inc ;; the amount of patches in between two roads in the x direction
6 E* m2 ]6 U( a5 Z/ h F" K& h grid-y-inc ;; the amount of patches in between two roads in the y direction6 i# h% Z2 m( R1 K4 w/ s( b
acceleration ;; the constant that controls how much a car speeds up or slows down by if, K0 o2 S+ k( _% g1 y( w6 r1 r
;; it is to accelerate or decelerate
3 ~' z! [. }+ w% W phase ;; keeps track of the phase
; s, [ f4 n( X7 O) W) s4 ~5 } num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure3 m. C5 Q: i; n- a0 @
current-light ;; the currently selected light" {: ]6 u+ U g/ B& S: I0 n) ]! W
$ V0 }& _- \0 F8 ?7 J1 W5 j ;; patch agentsets8 Q6 X1 W# h/ n$ b" ?
intersections ;; agentset containing the patches that are intersections- U h! R% e6 X" e3 g% ~$ f& [
roads ;; agentset containing the patches that are roads
; M! Z8 A) X! U8 d1 a3 K( |, X" []
5 s0 N; }3 R6 P! f7 G4 |* L0 ?
1 p) W( Y0 u/ k( F9 c- ?turtles-own
1 h# C) F1 O6 ]" X( B/ k* P1 g[
' j/ v9 d- w. d5 @8 r: J8 X speed ;; the speed of the turtle
. s# o- Q: V' t, |% E7 t4 D up-car? ;; true if the turtle moves downwards and false if it moves to the right
8 u: Y; ~) }- E/ J wait-time ;; the amount of time since the last time a turtle has moved
. U. o- ]# K4 _- d- v5 F8 g1 E; ~]
/ n- l3 j# i4 r6 n* Y* {
& x, m6 z5 V1 Zpatches-own. ?, U9 `6 J% o4 u: K; r
[. f* k" |/ m4 {) G) P3 p
intersection? ;; true if the patch is at the intersection of two roads
, x) J3 ^% o( [3 F9 ] green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ H9 m- {, e$ e+ v5 p ;; false for a non-intersection patches.
# H" _1 Y( i2 w; t- ]( v T my-row ;; the row of the intersection counting from the upper left corner of the
. K7 c2 `5 \! e% C g ;; world. -1 for non-intersection patches.
8 \) X8 P( N0 T% z' e& P my-column ;; the column of the intersection counting from the upper left corner of the" h# z) J) p1 Z* e3 ~ S
;; world. -1 for non-intersection patches.! n7 b4 r7 l @1 g* R" M2 H
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
/ X! k- P' w& U' ?, i" x4 @ auto? ;; whether or not this intersection will switch automatically.
. @; ], G$ ?- K' K0 k2 c5 C* z5 w ;; false for non-intersection patches.5 |" l. c- I! Z5 O- Y& |2 }8 @
]+ m% G q# R5 m2 m: c. f; Q
3 T8 {/ L, b6 Q3 D5 ]0 R$ A0 h
0 A7 V: Y8 z/ M% L3 |;;;;;;;;;;;;;;;;;;;;;;
7 f3 W5 Y9 a' T! O; o& w;; Setup Procedures ;;% ? E! R3 K4 E b7 i
;;;;;;;;;;;;;;;;;;;;;;) X' l1 L% u5 V/ K: v2 h( a
3 ~; Z0 Y/ ]" P$ n) z( r- U2 ]7 Z, Y- Y
;; Initialize the display by giving the global and patch variables initial values.
# K! u( U0 w2 R$ _ q& S;; Create num-cars of turtles if there are enough road patches for one turtle to( @+ R. J+ N+ \8 G, e
;; be created per road patch. Set up the plots.
* T* ~9 [8 w* S1 ?- [to setup; B% ~1 F+ K; d8 ?: K; _
ca# _; L% @$ J3 q. T% v
setup-globals& o+ T6 o0 c8 i! R. l# E" r
: `2 ^' W% P' x2 [ c' w4 y+ ]
;; First we ask the patches to draw themselves and set up a few variables! c; y1 S& x& w& b0 u/ H
setup-patches
, A, v& @/ R( ?- C1 @ make-current one-of intersections4 h0 b: z# D& o, T6 ]8 p) W
label-current
6 f0 k* G1 V; e4 n) K" Z3 j& j# l
' q E6 W. g* V$ J4 X" H4 R& X set-default-shape turtles "car"
0 j* N4 q; C* i/ ~2 J# J& t9 O; q* f4 m
if (num-cars > count roads)" I4 q2 B2 O* N; D8 H; U8 h
[
. y, |& z6 u2 `- e user-message (word "There are too many cars for the amount of ", R1 i# l0 C, _6 D
"road. Either increase the amount of roads "9 `3 {9 K4 Y$ V6 ]
"by increasing the GRID-SIZE-X or "0 ]0 a4 N" x4 V
"GRID-SIZE-Y sliders, or decrease the "
, Y. `! d# I: \7 L "number of cars by lowering the NUMBER slider.\n"9 J% ^. r5 B4 i5 G4 r3 z) x( i
"The setup has stopped.")
3 I9 g( s; H5 y) [5 l! m stop
# l; M+ R y- e8 u* O2 b; L0 c ]
! _- W8 f* Q3 k$ K6 \0 [
; X4 Z9 @0 a$ Q8 p ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color% a9 b" {) h* a8 A% \; c' X; {
crt num-cars
, B& y# D, b) Z: V% m [
}( W5 \, \2 S- o! P; j setup-cars
. K7 w+ y# [( G& Z4 h: P: r set-car-color0 V2 t' p; ]$ C! E6 {
record-data
# Y0 s. F1 @. d ]
6 [8 y4 L0 y' V" C7 ?4 T% y) n+ P" D8 @/ R; s9 U
;; give the turtles an initial speed- d( Y+ i/ I ~9 k Z X
ask turtles [ set-car-speed ]
7 Z# ~/ \2 u" L" U8 c9 Y+ {; L1 l! A
reset-ticks3 N( T; L/ U, J2 J; o+ N( G
end% l& Z+ v# `% t+ s
/ N3 w3 j, X y: E* v;; Initialize the global variables to appropriate values
; A% w3 j$ X5 N+ w2 Jto setup-globals6 j( O- q/ W+ u4 {' ~. \0 Q1 O/ f
set current-light nobody ;; just for now, since there are no lights yet
) J% }+ @$ n& F/ R6 S set phase 0
. X6 a2 j/ I2 H& k8 I. u( ~- q set num-cars-stopped 0
, q2 a& e' H* m0 ~, {9 [1 c$ s* v set grid-x-inc world-width / grid-size-x
$ u1 C& c/ p: Y8 G set grid-y-inc world-height / grid-size-y; C4 I9 L- I$ j
! ~! o: _4 |% U) B0 f2 b ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary) o; i. {2 M- V3 Y t; D$ v
set acceleration 0.099
& U: e- l# x7 t& K. D& z; |end* [7 |. Z9 A+ h4 v4 A
6 \/ M& J( a" }2 q! M;; Make the patches have appropriate colors, set up the roads and intersections agentsets,7 }" l5 ?0 r& X* h/ K4 v5 n8 R
;; and initialize the traffic lights to one setting8 {9 U3 C! ^( a' g
to setup-patches! [' ?2 N8 f j5 u. }. P
;; initialize the patch-owned variables and color the patches to a base-color
" j, D! Y3 n. y! w1 o! v/ U, v9 u# ^ ask patches% ?/ D g0 X0 ~' y) K; d
[8 q4 T5 V6 @. P3 O4 T/ K& T8 }
set intersection? false0 W$ R; s9 l5 E, p; V- }
set auto? false
( B& \) F4 I1 j# o! r set green-light-up? true
+ L0 D$ U/ [: C9 w, }) N5 O7 F set my-row -1" Z' F5 _! x* a* P) b; T
set my-column -1
; e: B4 K# }) a set my-phase -18 w' c& q3 V |! l3 G
set pcolor brown + 3$ _- `6 d- b, D
]) s; L0 e8 u& b
6 J" G5 e! G5 i+ R( F) m& a' X ;; initialize the global variables that hold patch agentsets# [9 H0 A5 g- ]) `/ X& f
set roads patches with( Y- x, z& N& B; s' q$ _
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. c' l$ i3 T! s3 k
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 R6 s4 l. p9 @0 l i" z8 B set intersections roads with
) I: i! Z6 K/ o4 d: ~# e [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
- g! @8 @0 ]* q4 U; R" f! j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]) ~* Q9 A/ g6 O# L6 M. F1 c% ~( U
& y) x2 ?" ?+ k* X% J' Q
ask roads [ set pcolor white ]. n( [/ a4 l4 k# _7 _9 M! B) E
setup-intersections7 C# f) s: @% m) z
end
% [2 X G$ ]5 U3 i其中定义道路的句子,如下所示,是什么意思啊?
l2 l* \% P) { set roads patches with
) }2 I0 O' S4 U3 r/ G) C; | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, A# x. G' d9 V9 Q L) G$ S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 h7 ~- C) r, g$ u7 M4 u谁能帮我解释一下[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0)是什么意思吗? |
|