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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。
7 a5 F b) x4 P' e* I& k- [netlogo自带的social science--traffic grid这一例子当中,0 ~. A+ t) k( M: _5 ^
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: g% @/ K1 ]- k2 g& N2 @! E grid-x-inc ;; the amount of patches in between two roads in the x direction
1 L, D9 m+ a0 \8 v grid-y-inc ;; the amount of patches in between two roads in the y direction
& p3 Y# R4 V/ h- u* o0 m* T acceleration ;; the constant that controls how much a car speeds up or slows down by if t1 }6 Q/ o* H- D ^; \$ K; V
;; it is to accelerate or decelerate" F# y% V+ n8 q8 L( G. P
phase ;; keeps track of the phase
) r+ T+ {# p1 s+ j2 H: f num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure2 o" a9 e9 b. t4 P6 V
current-light ;; the currently selected light
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;; patch agentsets
" W/ C) h5 {6 I; F& b: g: r intersections ;; agentset containing the patches that are intersections
9 t8 @- X' |) C5 r3 L roads ;; agentset containing the patches that are roads
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1 s6 J9 Z4 q% s9 u rturtles-own* x/ |; j, I2 Q: h
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speed ;; the speed of the turtle9 U" C. @. W$ E- } Q9 Z
up-car? ;; true if the turtle moves downwards and false if it moves to the right$ l- i' x' ], z+ E5 W, U+ U1 L2 N
wait-time ;; the amount of time since the last time a turtle has moved
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% x, t: S% h2 S' X/ p# X( P @+ Bpatches-own
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" I$ G1 g E j2 A intersection? ;; true if the patch is at the intersection of two roads1 j. f, C) c0 S# k5 i$ `- u
green-light-up? ;; true if the green light is above the intersection. otherwise, false.& n+ ~0 X/ i7 f0 h0 s. j
;; false for a non-intersection patches.* N( k1 Q; b% ` r
my-row ;; the row of the intersection counting from the upper left corner of the
% r. D2 c3 F5 T3 ` ;; world. -1 for non-intersection patches.
K( E, ]4 l' Z% m my-column ;; the column of the intersection counting from the upper left corner of the
/ [9 R% @% n) ~8 J ;; world. -1 for non-intersection patches.0 m: q% P# [ p
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
/ v; P, B6 ` Y$ P. s: t2 U auto? ;; whether or not this intersection will switch automatically.% P! ~' s) b; \0 X4 e& y& ]6 n L
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;* {$ t' Z) q8 j5 }' h
;; Setup Procedures ;;) z: x9 F5 p; E& T
;;;;;;;;;;;;;;;;;;;;;;/ h( K6 Q B3 c9 q+ C7 Z) x
5 j3 b3 M* [5 C K6 V+ D* Y;; Initialize the display by giving the global and patch variables initial values.
1 @8 D4 k- k- \% \% c+ E1 t;; Create num-cars of turtles if there are enough road patches for one turtle to
7 p* s2 K) S) t% h% x! f;; be created per road patch. Set up the plots.
# s0 n$ Q$ r# X$ }to setup
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5 [; u5 K. u7 v, S setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
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e: n0 `. X- k' f2 i: f make-current one-of intersections4 F5 G0 O7 q2 M% H; }
label-current
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set-default-shape turtles "car"
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. K* c5 j% x$ P- z. e+ K& A8 `: W if (num-cars > count roads)
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5 L: u0 [7 \' R P7 { user-message (word "There are too many cars for the amount of "2 q9 a- y' V* F$ M# `& k" S
"road. Either increase the amount of roads "
) ~2 n5 B3 @5 Q( T: m I- P- J "by increasing the GRID-SIZE-X or ") e- }; N, K% I) I$ y7 v# }" H
"GRID-SIZE-Y sliders, or decrease the "+ q; ?+ v- x7 _; k1 r0 W
"number of cars by lowering the NUMBER slider.\n"- s' h4 K% x; e
"The setup has stopped.")% t5 ~- q, c) |; N
stop% y& U, }; A3 V! v# |# F
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8 I5 Y! I3 z1 X0 b ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 h2 D9 s4 Z% C6 [ crt num-cars5 _1 @7 d* _% e8 j3 n+ Z1 w
[( {2 ]) S% n8 @
setup-cars/ y8 K( J6 @6 l
set-car-color
! b- b- ~6 {3 E5 {" r record-data
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& A1 ]( o. d9 q8 s ;; give the turtles an initial speed
. \! i, k* L. O2 y. D' G1 V8 \8 Z ask turtles [ set-car-speed ]
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reset-ticks
& I4 n' S1 V1 ~) _end
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3 F& B9 F' E( M;; Initialize the global variables to appropriate values& }( m3 k$ y. e( R* I
to setup-globals6 m% [8 j2 @) G2 z8 m
set current-light nobody ;; just for now, since there are no lights yet
- A* l0 D7 d, D1 o% Y3 Y+ M9 k; v+ G set phase 05 j% F$ n$ E5 r9 D# s' Y
set num-cars-stopped 0
) [0 Q+ w0 j& N* @( v- p i, }% S set grid-x-inc world-width / grid-size-x
7 m+ o2 q. T+ X J set grid-y-inc world-height / grid-size-y
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2 A G4 @, H7 w, _$ T& I5 Y ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary* A' A- s( E% h, `: b1 T* S
set acceleration 0.0993 z' _4 M1 W5 ?, R, a3 ~$ V
end1 X! o4 ~+ D; V+ ]. j1 f
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
1 R) |; L2 R6 W3 {3 H: K;; and initialize the traffic lights to one setting
/ B8 c" {3 y& d" F/ w! [to setup-patches
$ h- R* ]+ y; t* h. }" X% V( g ;; initialize the patch-owned variables and color the patches to a base-color: K# V: \/ p8 z7 T2 Y
ask patches6 O0 O g- M5 S; s' j7 I
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set intersection? false4 h# f2 M- N( @* g# K7 X3 D
set auto? false
0 x' O& u+ k8 `1 m+ J set green-light-up? true
; a- b9 Q3 c: t, b: Q- y set my-row -1
9 Y: x. y! T) E- t9 b set my-column -18 Z! z1 h9 \' Z2 s1 T* d0 m
set my-phase -1
, v1 i5 u+ m: X1 {- }4 ^8 Y; L2 ^, q set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets# t/ S, p# R/ m6 d4 ?/ \7 i0 O9 w
set roads patches with. Z# m6 d! f: b" h) Q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 M- p: t+ k! _) G% t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 \/ I, A J0 j set intersections roads with
- r6 y# t- V/ x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and1 D/ ?2 \: r1 m0 a$ t8 J
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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4 o0 a, e }" @& T ask roads [ set pcolor white ]
# {! m+ o9 S7 j& k" c- C1 d 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?" `/ c& S, {. c
set roads patches with0 n* I6 A+ H. T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: _5 d" B/ k" ]! a; R5 K/ Z! E' W
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
{& M5 e2 I9 Q( P) `" [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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