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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。
* ]- b' n/ q: T, Q8 wnetlogo自带的social science--traffic grid这一例子当中,, h; y* { }5 ?! ~/ {9 X
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
5 G0 y) R# ?* G n$ Q: M" n grid-y-inc ;; the amount of patches in between two roads in the y direction1 V4 k" m9 I! E. t/ w
acceleration ;; the constant that controls how much a car speeds up or slows down by if9 N8 q" B W4 g6 }9 u
;; it is to accelerate or decelerate; N+ f* j; @" _0 ?, O+ @
phase ;; keeps track of the phase
, x1 K4 y" `7 O/ k( o, f9 W4 w num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure& c/ W1 p i0 O- a. H- M
current-light ;; the currently selected light# ]% O' n% `8 o# ]/ x' v
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;; patch agentsets
$ v( ?( Y" G9 N0 t6 g intersections ;; agentset containing the patches that are intersections
: e3 S d% s* ~- [/ M- y roads ;; agentset containing the patches that are roads- p* M3 Y5 N# f5 Z0 {; C
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( z5 f% P j/ ]) P3 s/ zturtles-own& U8 H9 S, a; v) z: k; H
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speed ;; the speed of the turtle
8 o! O9 [2 L: Z% }. \( k" [" f up-car? ;; true if the turtle moves downwards and false if it moves to the right" J0 c1 z P+ m7 @. U/ ]6 `2 [
wait-time ;; the amount of time since the last time a turtle has moved+ I# [9 A6 n% S* K" s$ W0 N
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& x0 t/ x+ m4 e+ Bpatches-own
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intersection? ;; true if the patch is at the intersection of two roads
! A' @) {5 p5 x green-light-up? ;; true if the green light is above the intersection. otherwise, false.
( p& _2 w1 m9 F9 v6 k! d+ _8 {/ C; | ;; false for a non-intersection patches.
. | s4 k) @0 P) ?2 {! ^% r+ {: e. u my-row ;; the row of the intersection counting from the upper left corner of the6 {/ V6 N& r. t7 {- i) O" F! A, y
;; world. -1 for non-intersection patches.0 b9 o; w1 J5 E! X3 N! G# L
my-column ;; the column of the intersection counting from the upper left corner of the
" z0 q8 @/ R' U8 ~7 q; v- C! G ;; world. -1 for non-intersection patches.8 z# f9 D( C4 v l( v2 H$ w
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
* y+ M/ h2 F" E0 `# M' S& l6 Y) I Y auto? ;; whether or not this intersection will switch automatically.; K2 H. y7 f" I6 M! S( G
;; false for non-intersection patches./ F# `* f) v3 ^& }3 K1 }
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* r3 J8 A5 r/ {4 n. };;;;;;;;;;;;;;;;;;;;;;7 Q5 F9 E2 J/ l) x
;; Setup Procedures ;;2 P% ?% Q$ \2 ~ _
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
4 [5 k; y# a: C% K# s( y;; Create num-cars of turtles if there are enough road patches for one turtle to
K7 K1 T4 Y( z m;; be created per road patch. Set up the plots./ I* I2 `# a& ?2 z% h$ I, B& {9 @5 _
to setup
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$ u. b5 _! x4 h9 a. [) c setup-globals% h2 _/ ?' z: @- d4 B3 n
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;; First we ask the patches to draw themselves and set up a few variables
/ k5 x1 Y' W% E# J setup-patches
6 E* J5 t' s3 [: q" T, \7 q make-current one-of intersections N" L( z. e; R3 }" o X" g
label-current& z, e, }3 v$ {
. ?( h6 |5 n6 s8 D& y% N set-default-shape turtles "car"
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if (num-cars > count roads)
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5 j4 B/ n% a2 M% T4 K' d- A user-message (word "There are too many cars for the amount of "5 |# V* x+ d! [+ E3 L
"road. Either increase the amount of roads "6 `6 ^: P9 q) M6 @' q
"by increasing the GRID-SIZE-X or "1 d: H. K1 O4 B# V2 ^# t& J# N
"GRID-SIZE-Y sliders, or decrease the "
. E7 v! q5 U+ T$ k "number of cars by lowering the NUMBER slider.\n"& y2 a- Q9 C! m9 J
"The setup has stopped.")
8 X/ o, k4 }! e0 x( f, b F stop9 q ~ e# P& r0 o9 i% F
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' k0 L+ a- ?$ y: m9 n8 J- @9 t ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
3 |( T8 ~# A" M crt num-cars& I% H: I, |2 b2 t. i0 U$ }1 s& s5 |
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& S, R* M3 P6 q) K( @ setup-cars; _6 i2 I* H# C3 ~3 d* [6 a
set-car-color
; g3 x4 T2 a% _ record-data: Y1 g* [. u! X8 T4 [/ {: Z7 [) ^
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# @# a! b9 D4 ^- h' [ ;; give the turtles an initial speed
" o; D# I( v4 Y; Q ask turtles [ set-car-speed ]
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reset-ticks+ j9 s- P# i- e; t6 i" k4 l% K
end7 S3 ~: i8 o$ M" T7 F# m. m
, Y3 }+ f1 B, L# u! k7 ^; d;; Initialize the global variables to appropriate values" S' B* G" t' @5 q( r- W, B7 E
to setup-globals
; f: W- G/ {# Q8 V set current-light nobody ;; just for now, since there are no lights yet
2 n2 h, P: M% u/ q: W set phase 08 g0 E ]8 G+ ~: J9 J
set num-cars-stopped 02 Q9 k; g1 {3 j2 E+ K
set grid-x-inc world-width / grid-size-x
& o. l' _) u$ ?* Q& p set grid-y-inc world-height / grid-size-y2 L( o4 u+ {8 H: K
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
- O8 f9 `9 c; n/ p5 ] set acceleration 0.099: \$ P" d3 r0 E! o( |! ?0 k$ U/ e6 D
end8 Z$ ]9 K3 D3 d1 Q5 P
4 U/ b6 A$ f. G+ v3 a. n6 n;; Make the patches have appropriate colors, set up the roads and intersections agentsets,# H+ S7 P6 x; K
;; and initialize the traffic lights to one setting* V3 b1 r+ y- R4 l, m' |- h
to setup-patches
/ X) v7 x$ b# ?. h$ C: w! n ;; initialize the patch-owned variables and color the patches to a base-color
6 _: u" y& W! l, D ask patches
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/ R3 C6 Q6 k+ ?+ p( ]) K1 N( R set intersection? false4 R6 f O$ M5 g5 A8 M/ [) g. L) p
set auto? false8 u4 u% L& ?( H1 v
set green-light-up? true6 n2 d& p- A: R+ V. I8 n0 L) I' l9 r$ I
set my-row -1* l, k0 s; M8 s) H$ p
set my-column -1
7 a. y5 G/ i$ J) z( X3 e set my-phase -1( R! _0 T9 g. Z8 d) w1 U- b
set pcolor brown + 3$ t. G" K1 p E3 L8 S& r1 W4 C3 G
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;; initialize the global variables that hold patch agentsets5 ]: I; O# J4 q
set roads patches with, M2 i( U# e7 \8 ^% a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 i+ _( G& Z1 e2 V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 w# o( H/ ~- ` set intersections roads with
X X) x% Y% W% ~- ^" L5 ~- C. q* M [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
6 R. i! ?+ ^6 I- N! P (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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8 n' L; i( o3 w ask roads [ set pcolor white ]3 I3 X0 U' L4 m1 a& q0 U
setup-intersections6 J6 x' N; W7 }3 u% B! M7 p' a
end
8 M' F/ _5 C0 j: {- _0 N其中定义道路的句子,如下所示,是什么意思啊?% X0 d$ f( K" T$ i! i
set roads patches with
6 t2 e4 `) T) I# x+ ?1 S9 i [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& g" V4 h" T! ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* A$ [- T) i' A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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