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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 }% z, a7 A; S( P
netlogo自带的social science--traffic grid这一例子当中,: F. m# k1 @( T2 A8 e8 k
globals( R2 n9 m4 t, M" `
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0 h/ H$ D# t+ r9 |* p$ `- o grid-x-inc ;; the amount of patches in between two roads in the x direction( ?. a- n, T* K
grid-y-inc ;; the amount of patches in between two roads in the y direction. G( I; X0 P+ e' g5 O" h
acceleration ;; the constant that controls how much a car speeds up or slows down by if
1 ?1 G/ E5 i" N; q. d ;; it is to accelerate or decelerate
5 o, x2 G! A/ `* |' R0 } phase ;; keeps track of the phase
1 B v) d' x' z% ~( j# u1 r num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 z3 V% p( B$ @2 J4 D1 V current-light ;; the currently selected light
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;; patch agentsets
' V- ]- N+ V% o. }% V6 Y1 |% V intersections ;; agentset containing the patches that are intersections7 b0 w+ \% [% G( R
roads ;; agentset containing the patches that are roads
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turtles-own4 ^% @# {* Y5 L
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0 ^# F4 l* e5 ]# J/ p speed ;; the speed of the turtle
5 p1 @. z6 k# ]) Q1 Q up-car? ;; true if the turtle moves downwards and false if it moves to the right' E4 Q) Z/ s. u1 }5 G& R
wait-time ;; the amount of time since the last time a turtle has moved
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% w- W1 w: _3 [0 R$ W7 n npatches-own
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( D$ t/ O2 [; k! B' ~ intersection? ;; true if the patch is at the intersection of two roads
& _* ^0 }* b8 K; Z green-light-up? ;; true if the green light is above the intersection. otherwise, false.
0 W. V. L" f) E ;; false for a non-intersection patches.
1 [3 d8 K3 O8 P* }! p& J: N my-row ;; the row of the intersection counting from the upper left corner of the7 E& Q. J3 b; G# d5 M) B9 B
;; world. -1 for non-intersection patches.
1 Q. S8 O7 z+ U0 D my-column ;; the column of the intersection counting from the upper left corner of the1 r" ^6 T/ J' @) g2 }* B& q9 {; g
;; world. -1 for non-intersection patches.
% I. o E8 V6 B: _ my-phase ;; the phase for the intersection. -1 for non-intersection patches.* ^7 N; a% P z+ l. D
auto? ;; whether or not this intersection will switch automatically. |+ T' A3 t: T
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
" j; ]6 h: n u4 r;; Setup Procedures ;;8 U0 g- v0 G) Y$ G" k# N
;;;;;;;;;;;;;;;;;;;;;;
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F( Y9 V% d) r0 U3 {. p;; Initialize the display by giving the global and patch variables initial values.
% X' q8 X4 I, P& V/ Y& _4 j;; Create num-cars of turtles if there are enough road patches for one turtle to/ P& W( t* y" O" L: S, k- l: D8 b3 a
;; be created per road patch. Set up the plots.; h2 U* F5 L0 e2 w1 C
to setup
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- B! ?) Y6 A) k7 Z: j setup-globals2 a, S$ [" Q/ ^2 g' `
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;; First we ask the patches to draw themselves and set up a few variables9 t1 b' n+ R2 \9 W# f* ^
setup-patches+ x6 y! L3 |! e$ q- u0 @
make-current one-of intersections7 W( F7 b& K6 H% x
label-current
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1 ~4 o5 R% O+ B% b set-default-shape turtles "car"' c, K/ _. [! G4 U
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if (num-cars > count roads)
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7 e7 p' F% T0 H" \* B2 y4 H, f user-message (word "There are too many cars for the amount of "" b5 ^+ u; O# k. n& O/ P+ N
"road. Either increase the amount of roads "
; t$ ]1 P9 k9 J+ e/ {8 D "by increasing the GRID-SIZE-X or "
! d) g. P8 _" u L# S "GRID-SIZE-Y sliders, or decrease the "' r8 o/ z# ?" E( K4 ^# I; z
"number of cars by lowering the NUMBER slider.\n"9 s5 D' \6 o# M+ `
"The setup has stopped.")
3 K" ^3 n0 z1 [" ]. Y; n4 w1 s5 D stop8 U# _& ], z5 p3 ?5 b' c- g
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color7 `' b% u1 L8 R n* ]* i* F
crt num-cars: \3 u/ m0 |( T" y M4 F
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0 r6 `/ j% Z( i* h# e setup-cars
+ Z% _4 ~+ `9 x7 [0 h set-car-color
: Q$ l* e0 t% e- y' G record-data! d9 Z5 t/ c: ]' K6 D8 Y
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. ]3 F5 H a9 d. q ;; give the turtles an initial speed
+ N7 Q9 r) o" F# Q, c) y& i* \8 i ask turtles [ set-car-speed ]: i) F* Q2 U6 ~: ?( u; T
! {4 g, G2 U0 ?" d' C reset-ticks
: X, I' L# b2 r! c2 y- ?) Y# `* f0 Dend
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;; Initialize the global variables to appropriate values
2 y$ T N. v; v; h4 ^& Y' f/ Z; \! X9 }$ lto setup-globals' H0 n* B: q3 \3 B$ {4 ?, G- ?) D: V
set current-light nobody ;; just for now, since there are no lights yet
$ N0 L# o% N! F" M% } set phase 0
& q" P, T+ B' u2 O: o set num-cars-stopped 03 E5 I% p( k4 M, N
set grid-x-inc world-width / grid-size-x
% W5 ?2 y0 ]+ Z" l- _1 j, ? set grid-y-inc world-height / grid-size-y' i1 Y. S; C. ^# A' ?4 l8 b4 i
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary, q9 G d" m8 ~$ P, t5 n/ H; w( d2 `
set acceleration 0.099
$ H. x# [0 b' g2 Aend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 x! e W. F/ y5 T6 J6 I1 L; X! n
;; and initialize the traffic lights to one setting% `( x( B, O; ]- W6 n4 H/ \
to setup-patches2 Q7 t8 C# | j2 x" ~! R h% }
;; initialize the patch-owned variables and color the patches to a base-color
$ Z- b4 d, r& f! _1 a ask patches4 i. E% V o4 d' u' P
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set intersection? false
3 c4 g# v/ a( b2 u( k5 _ set auto? false
0 O. S( [, a# K6 h- ] set green-light-up? true0 b j; |6 F: c
set my-row -1
% c. @* Y! i' S2 X1 L set my-column -1
Y8 L0 o2 M7 I+ T& a6 y: N: X set my-phase -1
" ?. p( J0 C0 Y# m6 o set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets' }4 v2 A }" z: P0 {/ v4 T
set roads patches with1 u4 }- \4 A- O) T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& y) b! G+ b* W/ c" b" J% G# x/ R (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' I) V" ^4 W' T& O7 Q; ~+ \4 [7 c
set intersections roads with
7 L! H3 b: H$ G, f( [. g$ D* S% k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and. w7 Q3 A4 d+ \ i% d J5 @
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]' s/ o5 H2 j7 r1 u, D3 [
setup-intersections
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0 M9 O4 W+ w! V8 r( ?% N8 r其中定义道路的句子,如下所示,是什么意思啊?5 K3 j( e% P: J$ r
set roads patches with
3 @* C p9 ?# w- [5 } [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 ^. I0 ^9 |7 z( n8 j
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" V5 J9 Q/ p* J7 ?& U" `; R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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