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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。' ^5 l, g) W7 P+ _% h1 R" v
netlogo自带的social science--traffic grid这一例子当中,$ g3 q* ~3 ~6 [
globals. o- P% T. i1 [! c! o
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grid-x-inc ;; the amount of patches in between two roads in the x direction
+ b: u+ q7 f' T* ~0 y6 r+ O1 ~ grid-y-inc ;; the amount of patches in between two roads in the y direction' d6 i' t# |/ b7 U' H* U
acceleration ;; the constant that controls how much a car speeds up or slows down by if2 |6 v5 |/ e( c2 K' J* `
;; it is to accelerate or decelerate5 _, ]( c! `; [3 L. Z& {" H
phase ;; keeps track of the phase
0 d& h7 B+ S& a$ C& U num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
3 }( j# h/ U% c0 ^9 i3 q current-light ;; the currently selected light
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3 S. M$ V8 W' z. F/ G, M ;; patch agentsets
" y- @: i0 Z) x. T3 W. k) R intersections ;; agentset containing the patches that are intersections
) k- c) t& S3 J( y roads ;; agentset containing the patches that are roads& v: m* r% T* S# O% G2 c
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2 }5 R* a3 ]1 k8 n. c+ dturtles-own
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speed ;; the speed of the turtle/ ]" N* b5 T& E% Y4 y' t
up-car? ;; true if the turtle moves downwards and false if it moves to the right) n" y! G! U: S" y9 m! O2 `
wait-time ;; the amount of time since the last time a turtle has moved8 z+ Y$ u3 D1 t6 r; R9 O' {
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% [, Q1 |) l5 D* H9 v. ~( xpatches-own
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1 @7 j3 n1 d( H& M% ?; D1 }% h intersection? ;; true if the patch is at the intersection of two roads
6 ^0 H. p- ^/ _% x+ _ green-light-up? ;; true if the green light is above the intersection. otherwise, false.
, v9 g+ k# t, ~1 U: f" F/ U ;; false for a non-intersection patches.
& w) j0 h! T+ T( M my-row ;; the row of the intersection counting from the upper left corner of the! D& @& e$ z3 b5 V
;; world. -1 for non-intersection patches.
7 [ J' V0 l v( K$ Z my-column ;; the column of the intersection counting from the upper left corner of the
6 h6 ?/ k4 o4 k1 T ;; world. -1 for non-intersection patches.
* e" q+ p, V7 ?6 v+ t( ] my-phase ;; the phase for the intersection. -1 for non-intersection patches.
^% ]; d5 w1 T9 ?; F, y auto? ;; whether or not this intersection will switch automatically.9 r. n3 b( ~4 p1 E- ?2 t1 z
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
3 L6 G% R. i& M2 w% d$ ~;; Setup Procedures ;;: g% ~$ _# U- S& q
;;;;;;;;;;;;;;;;;;;;;;
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, k7 S% U& A* F" z;; Initialize the display by giving the global and patch variables initial values.3 U9 N9 M* t \" N! S" d
;; Create num-cars of turtles if there are enough road patches for one turtle to
$ p* Q5 n4 A+ x5 m6 w;; be created per road patch. Set up the plots.6 I6 @- x+ r! i x# `4 Z
to setup
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" s& e7 M0 o+ Q8 M0 T setup-globals
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( D6 ?1 D5 j: M$ y! l/ t! i ;; First we ask the patches to draw themselves and set up a few variables
3 m" [* }) I; G, ] setup-patches; o7 \6 T) e) i2 n N8 d6 j
make-current one-of intersections' M2 I7 ]8 q: H
label-current
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) \# e2 Q% {2 Z set-default-shape turtles "car"
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. D7 J7 n5 p3 c# u+ X0 w, I3 y if (num-cars > count roads)
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4 D+ @# _9 _, u8 v% U/ P2 p user-message (word "There are too many cars for the amount of "
; E* X0 N$ [2 n "road. Either increase the amount of roads "
* p9 R Y- C8 L% U \ [ "by increasing the GRID-SIZE-X or "
1 z' O/ E M) m" I "GRID-SIZE-Y sliders, or decrease the ": h5 ]0 c% \7 `5 h3 q! b, v
"number of cars by lowering the NUMBER slider.\n": Q+ y E7 x, h7 T! T
"The setup has stopped.")
) E9 M9 m% B% c) u8 n& J stop
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! P9 p& Z0 l7 A$ d4 g) r ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 m! P! G+ _5 l! \: U" J' ?$ c, |3 F crt num-cars
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[" q' B7 Z1 Z5 R setup-cars
7 n5 M/ o7 h8 V/ [6 L1 m3 }& x0 u8 Z1 w5 [ set-car-color
8 i7 C A4 P/ l# T6 T record-data( f: U _3 s; t6 }* S7 ?
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3 a- v- I+ ]+ U5 j% s8 e ;; give the turtles an initial speed
; s( u. U" M6 i$ x+ }: l ask turtles [ set-car-speed ]
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reset-ticks
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( L6 S4 A |! S( U7 B, D;; Initialize the global variables to appropriate values+ E- \+ b' |7 ?7 o+ ~$ ^
to setup-globals. I# n" g( W& w% F8 Y: a. p
set current-light nobody ;; just for now, since there are no lights yet. N. }2 H7 n# y- w
set phase 05 Y# e% b9 u) E6 w& E
set num-cars-stopped 08 b* W* U& ~" T+ [$ {0 R. a* X+ w
set grid-x-inc world-width / grid-size-x
7 x6 A, L8 [+ W9 s) c3 z; N& t set grid-y-inc world-height / grid-size-y7 ^6 M9 V$ U/ U! b% S) a$ f' X
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
, A7 [. h+ I& o7 C* q' O set acceleration 0.0996 f0 B( ?: Y% F$ k- Y* k" j
end0 n$ `, Z d% M5 H! L
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 ]5 ^; k: C" r M& ^" R;; and initialize the traffic lights to one setting
: }# m$ I' s% v9 c1 O* S2 c1 K) Sto setup-patches6 c, ~! T. S6 R n: h+ c! {3 |
;; initialize the patch-owned variables and color the patches to a base-color0 x3 s+ j9 D' v( f
ask patches+ t$ n: v% h, W
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- i$ G2 t) L# _' j1 s% O2 ~* V' X set intersection? false
0 F# { i' u7 x9 y4 \+ j+ K% @% D [ set auto? false; k" d1 M6 i( x6 Q. E- C
set green-light-up? true
Y @5 Z# _! y0 I1 e O( J* G set my-row -1; {. Z' j" ^$ w8 S
set my-column -10 N: [" r( S- s0 e2 b& T
set my-phase -1# G2 R# ? ]! X6 d: j q5 J% b9 E
set pcolor brown + 35 M7 n( d6 d! F
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;; initialize the global variables that hold patch agentsets/ C0 j5 v) O& G6 I' x& u
set roads patches with
1 X% I. S5 ^/ w8 g [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ I: d* Z* @8 D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 w6 G X+ `9 ?+ f- D3 G$ r set intersections roads with! B1 H% K. @, u$ i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and2 U4 k& r" p( @+ Y6 `
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]; N4 t) b, P5 `& q% \; G
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ask roads [ set pcolor white ]( D5 q s3 @# k0 C' F. f6 z
setup-intersections
5 _8 a u: _' l7 i2 ^$ X6 ?end
' T: V; y% J p; R其中定义道路的句子,如下所示,是什么意思啊?
0 }6 K) j: s4 O$ d1 I set roads patches with
3 W& r# Z; _; U1 D! C0 ]" A [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ Z3 W& b6 X6 B (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 T; u' T K) C
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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