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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。
4 p! Z+ i) [$ Q6 V t( Y7 ^netlogo自带的social science--traffic grid这一例子当中," z2 L+ W" ]6 k/ B# B: o/ d
globals
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6 Z! q- m! f+ K( h$ a7 c grid-x-inc ;; the amount of patches in between two roads in the x direction
% Q \, ^6 Q1 P+ k grid-y-inc ;; the amount of patches in between two roads in the y direction
. k- N1 ]. @( E' \! | acceleration ;; the constant that controls how much a car speeds up or slows down by if2 }: Z/ j7 M$ d o: }' J* b) c
;; it is to accelerate or decelerate$ p/ L% @ Z* }: q
phase ;; keeps track of the phase! {# v; P2 h& C6 u
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure/ ]. e4 `/ r, Q0 g3 _/ C; I9 F
current-light ;; the currently selected light
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* M" v$ G& W* z2 ]. t. d ;; patch agentsets
0 X% K" S( x9 t intersections ;; agentset containing the patches that are intersections
3 Y8 H6 X ]4 u% p! B. u/ t: D roads ;; agentset containing the patches that are roads
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turtles-own. t# l; ^1 Y' I! ?- l
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' w9 S+ S. \. k% r8 ^9 Q2 A speed ;; the speed of the turtle4 p9 I" b) W) `5 `$ Y2 |
up-car? ;; true if the turtle moves downwards and false if it moves to the right8 F: w+ D3 |- i
wait-time ;; the amount of time since the last time a turtle has moved
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# q4 S+ F) t! b7 T+ @7 Z3 Cpatches-own8 y6 [" p5 W0 Z# w5 K
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intersection? ;; true if the patch is at the intersection of two roads& K3 H) h6 s6 Z0 g/ `- D
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
, x _# u9 K9 o t3 z2 | ;; false for a non-intersection patches.
) o! X0 i5 h' r1 `$ Q7 e2 S my-row ;; the row of the intersection counting from the upper left corner of the( ?! L+ F e( D0 g1 [
;; world. -1 for non-intersection patches.
- v' `- P# g* t( g: d' q: b# g3 {& m my-column ;; the column of the intersection counting from the upper left corner of the( l/ \3 K: B2 K$ L7 ~
;; world. -1 for non-intersection patches.
- W% ~. F& s0 a8 Q4 _; s my-phase ;; the phase for the intersection. -1 for non-intersection patches.' _: B } K3 ^4 R( S, i3 y r# N
auto? ;; whether or not this intersection will switch automatically.
! R7 C! S7 U0 O3 N, G' K ;; false for non-intersection patches.
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% ^# u9 c+ v! Y, m$ @) h;;;;;;;;;;;;;;;;;;;;;;. D6 H0 Z5 G$ [) C7 D
;; Setup Procedures ;; m2 u8 H" Y, R; [% _
;;;;;;;;;;;;;;;;;;;;;;
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* L& u0 e5 Z+ h3 }! v+ e. H;; Initialize the display by giving the global and patch variables initial values.) W( q' y4 }. ^ O
;; Create num-cars of turtles if there are enough road patches for one turtle to& ]; ~6 m [9 Y# X
;; be created per road patch. Set up the plots./ x1 ^; }- `& }/ e3 G
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables4 D; s- G2 X$ d) y* Z* Q
setup-patches
1 p' U3 q9 d+ K8 |" V4 o make-current one-of intersections
: [3 d7 B6 _0 f) q+ Z) n label-current& Z% U- ^1 m6 ~) b% }8 R# @
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set-default-shape turtles "car"
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, V1 z4 \& Z- j4 I0 Y+ i if (num-cars > count roads)$ u: l. C) J- B) F
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user-message (word "There are too many cars for the amount of "" w5 e5 r5 h* L6 n& y" t5 E7 {8 B
"road. Either increase the amount of roads ". m. R5 W8 s+ |2 ~% L+ N0 l
"by increasing the GRID-SIZE-X or ": B( ]( e5 X1 o% F# ^
"GRID-SIZE-Y sliders, or decrease the "0 K0 e# v1 k! e: V: \7 U" {
"number of cars by lowering the NUMBER slider.\n"5 x) C4 ]) U5 u
"The setup has stopped.")
% f" q6 ^) [& ]& U, T( ?8 |: h3 P5 Y stop( m/ o, Q, D; D
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
9 k: k4 C! ^' [& ~ crt num-cars F8 a% |$ F. |9 r
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setup-cars
6 l1 s5 b: d+ \, I- ~ t set-car-color
; E( P4 Q& U/ N3 b2 f$ T: b record-data) ]& b/ Q+ b0 C2 Z. b
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;; give the turtles an initial speed0 L9 @ F$ P* Y$ [
ask turtles [ set-car-speed ]% B4 I/ e+ N7 N! i p! p
$ m0 ?" }0 Y6 r( R reset-ticks
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# [+ F' H9 C# C7 ~/ [;; Initialize the global variables to appropriate values
7 }3 |7 a# U3 L& G6 g) Zto setup-globals: ~; w7 u. M4 t1 i+ e9 G
set current-light nobody ;; just for now, since there are no lights yet
& ~ Z) Y+ T6 l# r set phase 0: H( p6 C! m# Z
set num-cars-stopped 0
( B9 I. }! ]7 L9 t2 k3 W z& g set grid-x-inc world-width / grid-size-x
; [2 g% z/ T" j% h- K8 A set grid-y-inc world-height / grid-size-y2 ]4 n8 Q6 [, B
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary. \2 c+ T; X8 I
set acceleration 0.099
+ @& t8 I) F: Z6 P. O$ L8 d7 u$ |end
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* t: b9 b; f1 r: J& G;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
5 ~5 Q5 J1 V- M- |8 j1 y. k% s2 m8 a;; and initialize the traffic lights to one setting
3 k* X. ]% [0 H: |1 jto setup-patches' W5 w& g; ~/ E) W( h" u
;; initialize the patch-owned variables and color the patches to a base-color
7 [! b! [0 J# z4 c" U8 v7 F ask patches+ f! M9 n% w9 g$ u1 {; t5 z
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3 H1 E% ] N" e9 u% a+ O3 r" W3 ] set intersection? false
" y) f% ]7 U/ T! s% L set auto? false
) }3 U( {+ ~! Z# f set green-light-up? true
/ a% }% S! p% Z2 | set my-row -1/ @4 P1 k4 `9 X L5 [
set my-column -1
* p- ]1 k- J/ Y' s& x set my-phase -1
/ Y* x$ ^$ e Q) X& ]' J set pcolor brown + 3- W! u# D0 e. A
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: S" }- E, L6 F. u ;; initialize the global variables that hold patch agentsets
2 j. q( u& f% Y; M G" Y! G set roads patches with! e9 D, A0 y; F& ~% q, o. Y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 S. i* \) L- \& B1 q+ `* h& q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ ?5 ^, z( w" h% {1 Q set intersections roads with7 W4 `& s! l* b6 N3 ~
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and5 r- M4 e8 O' e: K \
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ m/ _( ^3 H* q" o9 J) }% d
; G6 o' C0 i1 _1 s# t ask roads [ set pcolor white ]
6 o& x( }) u9 F: Z8 Q setup-intersections
$ D% Z4 S& v3 j! ~ [end
/ r6 X+ k5 K- n其中定义道路的句子,如下所示,是什么意思啊?/ e5 W7 F, P1 U( L! ?
set roads patches with
0 B7 O W# i4 ^4 h; L* D6 w6 d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" O! t9 z$ U, G" U6 T8 C3 g" B (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
7 n" y& }. C1 [ O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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