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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。
! D6 ?9 B! M# x6 U) f9 Lnetlogo自带的social science--traffic grid这一例子当中," z0 W5 W& J: [/ X+ C) B
globals
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/ A9 p. ]. r3 s3 c$ Q6 W; v! J grid-x-inc ;; the amount of patches in between two roads in the x direction
' {- y; f" k' d9 g1 X/ R grid-y-inc ;; the amount of patches in between two roads in the y direction
+ T% D& N ~ @& _! {9 W N acceleration ;; the constant that controls how much a car speeds up or slows down by if( {$ p) M! O9 \2 B7 b
;; it is to accelerate or decelerate
9 [3 \' F/ @+ ]6 L' N phase ;; keeps track of the phase1 M. }/ m: Y# V- ]
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
) j& C0 Q$ z- ?! N/ N9 ]$ q1 W: Q" H: K current-light ;; the currently selected light- d: g7 {7 @8 S2 T7 q2 r
. e' m0 T( H7 _9 i ;; patch agentsets: n: U! d7 I( ?7 t" ]; ]
intersections ;; agentset containing the patches that are intersections
( {7 n8 c& {2 W+ s! a% o/ B6 n roads ;; agentset containing the patches that are roads L# z, S% {- N1 U: G1 g; j
]
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turtles-own
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' s" A2 K+ Y& R speed ;; the speed of the turtle
) V+ S' m* i3 j0 r$ I' g+ R4 U up-car? ;; true if the turtle moves downwards and false if it moves to the right& h1 N/ Q h/ @4 l/ ~
wait-time ;; the amount of time since the last time a turtle has moved
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4 B" M4 n/ Y9 s& U0 k: m5 t$ Fpatches-own' A! A" |1 K7 ?! W; b
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intersection? ;; true if the patch is at the intersection of two roads
) g1 U% p% D; p/ c n green-light-up? ;; true if the green light is above the intersection. otherwise, false.
9 |; @/ Y/ v( b% @- F ;; false for a non-intersection patches.# _' \6 z2 I+ `; i, h
my-row ;; the row of the intersection counting from the upper left corner of the. A! j+ @% G3 d% W7 d' [+ p1 H4 d' ?, M
;; world. -1 for non-intersection patches.) M/ m9 k% F4 e$ H) z7 M; @! l
my-column ;; the column of the intersection counting from the upper left corner of the
$ t* y- }. @$ t ;; world. -1 for non-intersection patches.8 k, z" M8 W N/ v' Q
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
, b4 a6 P, A! b" }$ i {7 u auto? ;; whether or not this intersection will switch automatically.
4 n% I; Z; T" @0 Z ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;3 M6 q: |3 x) J' K
;; Setup Procedures ;;0 O3 `. q& s+ g( Y5 }) n+ V
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6 H: G5 R/ o% U! k u1 H, b$ I;; Initialize the display by giving the global and patch variables initial values.
3 x6 o, a; [+ k" {0 x8 u' g;; Create num-cars of turtles if there are enough road patches for one turtle to
* S* e" h* B! j e% X; T;; be created per road patch. Set up the plots.
7 k# W% x3 \: y3 y: u. S, Fto setup4 w7 k$ t( h! ~0 V$ t
ca
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;; First we ask the patches to draw themselves and set up a few variables$ ?& W+ e) q6 R$ X$ M2 a W
setup-patches
: B1 G7 _" e/ v3 B' g make-current one-of intersections
- d2 M1 i f# A* n7 m9 f/ V# f label-current9 h+ f7 j- {: {9 p
- W- [4 ]* ?. F% t set-default-shape turtles "car"
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if (num-cars > count roads)
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/ @, e, ]# o' s; L3 j4 O! k( W2 q user-message (word "There are too many cars for the amount of "8 c- i* ^3 o# `3 X! r1 Q
"road. Either increase the amount of roads "
# o" h }3 g N "by increasing the GRID-SIZE-X or "& c+ }: l9 \. T! g
"GRID-SIZE-Y sliders, or decrease the "; g. ]( G4 f) n' s) N
"number of cars by lowering the NUMBER slider.\n"
2 I B0 P7 M) ]+ D! y% W "The setup has stopped.")/ \9 {6 n) n5 p v- {2 ~1 v2 \9 h
stop: t* O! \3 ~( a+ L% G% V' j
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; s; M' O+ A1 |: l& T. x+ Y ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color8 l; G3 _- _$ G" }; z
crt num-cars
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setup-cars
* ?5 d6 I& ^; x: Q0 N2 [- F+ z set-car-color
3 {' b8 e* H8 H# b# t" L record-data, p4 e1 i/ _( x5 e
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;; give the turtles an initial speed
6 K( [$ ]1 J, m; o ask turtles [ set-car-speed ]7 l4 s' N3 z+ _8 s& V' h4 Q* m
" t0 e, [" ^; U reset-ticks
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9 b; w! D& e5 o& Z6 Q;; Initialize the global variables to appropriate values
# Y' K0 G$ M( M! s* p; Hto setup-globals
$ g2 u1 N6 v, z& f4 L set current-light nobody ;; just for now, since there are no lights yet
' j: w( Y; x+ V7 ~3 T set phase 0' u( D7 f9 |: @2 l
set num-cars-stopped 08 ]' t% B8 K/ A1 X. Y7 Y
set grid-x-inc world-width / grid-size-x
! i Z. N" W+ J* Z set grid-y-inc world-height / grid-size-y$ U7 s: {. z2 h# f
! C# y6 h0 m: H- a- J. Q ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 A1 I5 U, i( p+ }
set acceleration 0.099
* J" w, v7 \; v. ^5 Vend
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+ O0 u' b2 C7 w;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' K+ X8 T0 R; E! C: P;; and initialize the traffic lights to one setting
5 V. |( T6 @9 Y! v* l: ?to setup-patches l& A z8 r& `
;; initialize the patch-owned variables and color the patches to a base-color
; l# z7 Z t1 C) X+ y- y, I ask patches
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set intersection? false
6 p7 c' r! ]$ L set auto? false
. B* b8 N5 Z$ z6 ]3 A# ^$ X. t set green-light-up? true, @' n9 v% G) e! S4 B( i9 V
set my-row -1
; C6 b. D" J( u' s, x set my-column -1, C7 D s6 ~* e. G3 c3 v' N
set my-phase -1
3 N4 I- h2 W; ]$ d' ~- `( \ set pcolor brown + 3
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y! D* H6 Z* _0 n# Z ;; initialize the global variables that hold patch agentsets$ M" C6 Z) J) i5 ] _* [
set roads patches with9 H; F8 P# ]. {, i$ j* I3 z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or+ J: R7 l, `0 S7 S2 n: P
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
+ p. W$ |" ?# U q ]1 e$ k6 z) t set intersections roads with$ h& ]3 ]' E( U$ U5 u/ B' i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and/ _) h \0 S/ s: F1 B$ w; \
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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3 ~5 \5 d* o r4 v, R* k( w ask roads [ set pcolor white ]
. { m+ a0 G% E6 I: s setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
; {3 h: b) o7 P! Q) Z' L set roads patches with7 G- b) F- |1 X5 m4 [# U( E
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or6 a: d# i3 l) \' Q. i& ~7 Y+ e
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 Z3 A6 f% u7 i' h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? |
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