设为首页收藏本站

最大的系统仿真与系统优化公益交流社区

 找回密码
 注册

QQ登录

只需一步,快速开始

查看: 9410|回复: 0

[求助] 在看例子时有几个问题看不懂

[复制链接]
发表于 2012-6-20 08:59:43 | 显示全部楼层 |阅读模式
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。
* o* l( H9 Q- K5 l% Cnetlogo自带的social science--traffic grid这一例子当中,
' }. e, Y9 G4 M& s5 _globals; M( R/ l" v+ ~" @2 S( S5 b
[* q# B) r" m1 q9 d' G( v! C
  grid-x-inc               ;; the amount of patches in between two roads in the x direction7 I5 s) `4 ^4 Y3 }
  grid-y-inc               ;; the amount of patches in between two roads in the y direction- Q7 U; s; K, G# ?+ c
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if. _' @$ U: F! t3 J
                           ;; it is to accelerate or decelerate
; \$ p1 T6 e9 T  phase                    ;; keeps track of the phase
1 \" r  ]0 N9 Y) i8 k7 e  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
" J4 E6 x% ~1 H7 g  current-light            ;; the currently selected light
9 e3 S# p# F* ]
- f4 m, B5 M( M; g2 w8 U' j3 s  ;; patch agentsets
, t( f$ i# w# T7 V) R1 O# `8 @  intersections ;; agentset containing the patches that are intersections% I; ]+ p4 p2 c# f
  roads         ;; agentset containing the patches that are roads  j* F8 P$ T# g! P3 m
]
, m; }# r5 u! D6 y" D7 P9 g/ E4 l( N& A  T, F4 ?0 R* s
turtles-own
8 S: x: C7 M" x[
* g7 `6 f( f! T8 C4 c# K% b9 l  speed     ;; the speed of the turtle. G: ~2 ?! ^' i$ O/ @/ V
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right+ ~- s6 x# Z* d
  wait-time ;; the amount of time since the last time a turtle has moved2 h7 f  x3 j( H: ^
]
) y$ R  N3 r+ q6 w  ]
3 u9 }7 T  [' |! r" Tpatches-own5 X7 c0 v2 B/ o7 w, c
[; C# y9 S9 S! D9 L# O2 p
  intersection?   ;; true if the patch is at the intersection of two roads6 l" x9 j+ H5 W# u
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
+ Q! ~& B7 p+ V6 M4 d7 h; q! l7 O: Q                  ;; false for a non-intersection patches.
$ j* n) Y0 w: |* V  my-row          ;; the row of the intersection counting from the upper left corner of the, D2 `: ^2 D4 T: \
                  ;; world.  -1 for non-intersection patches." K( z( m* Z  m( P
  my-column       ;; the column of the intersection counting from the upper left corner of the
2 Y" \8 W9 D- d- }3 L                  ;; world.  -1 for non-intersection patches.
9 M% h* Y" }$ H! S: Y' d. U  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
3 G( p+ [2 q+ B. D6 J2 _  auto?           ;; whether or not this intersection will switch automatically.
+ k% g  a4 P$ J$ W* J. M                  ;; false for non-intersection patches.
* q6 |, D' T5 _1 ?4 w" j. y! k]
5 k( o+ g  P& U; |# q8 d
* A+ u( ~. a  a" G/ \6 ~: @( ~! |  T4 }- \# F
;;;;;;;;;;;;;;;;;;;;;;
- ~+ S: d( O# \2 e;; Setup Procedures ;;
) }& y) p& \. W9 ?6 [/ n/ Y8 x5 v;;;;;;;;;;;;;;;;;;;;;;% x* ~& A% t, c6 ^! O& S

% s6 Z) K( ?& x, B1 n0 j4 j, Y$ e# h;; Initialize the display by giving the global and patch variables initial values.+ M& _6 u: m/ E. G# i
;; Create num-cars of turtles if there are enough road patches for one turtle to
" \, F" n* F5 u, @' W;; be created per road patch. Set up the plots.
6 y$ A7 t3 M  x7 j7 ^2 B; `( A$ t+ Yto setup; k4 L2 j  S. O1 ~+ m
  ca
5 w+ g5 z4 w# V! D( K9 Z; [  setup-globals6 H2 T! l/ w6 e" {- {' i7 v+ A) V  |

+ p0 n# I* I% R, B) z2 O  ;; First we ask the patches to draw themselves and set up a few variables
+ {: _* k' U+ Q+ C" Y2 f0 W  setup-patches
% h! F5 O$ t0 b  B1 d  make-current one-of intersections
; P) e  W; U. g# v2 K' M* m/ }4 t  label-current- W  f& [. z1 ?
3 J" |! J: _8 I- ?3 M/ d$ M' k; t) i
  set-default-shape turtles "car"# i- }4 S3 b. `  U! W
3 ]7 D* I# L3 C  o
  if (num-cars > count roads)
  j* b- b" A7 V  [5 \  M! ?/ W* o$ s
    user-message (word "There are too many cars for the amount of "
! ?, B! j$ j1 \                       "road.  Either increase the amount of roads "! l4 `" _9 l1 \4 V% R! F0 i
                       "by increasing the GRID-SIZE-X or "! _3 h/ ?. {1 r4 z
                       "GRID-SIZE-Y sliders, or decrease the "6 M3 j8 I  I& C2 k$ i5 M: V
                       "number of cars by lowering the NUMBER slider.\n"
8 y/ C( Q" [0 l7 Z6 q                       "The setup has stopped.")% C1 q; q# O+ k- a
    stop
* S4 _* E( m/ N% v  f1 |  ]1 |- P' y& D4 `, j8 C9 @2 [2 C* q
0 a: v! y# d) q7 p7 p' s0 k  \7 j# [
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color& R' C) c+ @2 k
  crt num-cars
! e7 ~3 w8 p) d5 u$ C  [. e9 @2 W) A1 t" F4 ~; b1 M1 t5 Q4 Q
    setup-cars4 i: r" n! U  I' q+ l9 j
    set-car-color3 T7 M7 [4 c8 ~% P+ g9 D3 k
    record-data" F/ t  S* P& a4 z3 }9 B$ c* C
  ]
8 g% `8 T! J+ b4 D. n  P0 u% P6 b% v* v, @7 i
  ;; give the turtles an initial speed
  X" U, q7 I# T: m" r  ask turtles [ set-car-speed ]
  X- e9 F2 A( v: Y! i  E. V* t1 @0 m* y+ W1 P* V- n6 d8 ~' s7 j7 K
  reset-ticks0 p, ^) v- m- X1 V
end, X9 @( m6 W  l% g3 q6 R
; I* v3 V3 x8 w! ?) g* M2 X$ @# w. y( g
;; Initialize the global variables to appropriate values
+ b$ {5 c4 N8 |+ S9 Mto setup-globals
: E' M: \. j8 d8 u) Z2 \# O0 p9 p  set current-light nobody ;; just for now, since there are no lights yet& }6 N5 v1 M+ b+ u$ X
  set phase 0. ]/ R6 i# s: B$ L. ]
  set num-cars-stopped 0
3 d8 p5 G2 g' M+ D" U7 ^* S  set grid-x-inc world-width / grid-size-x5 |- [, ^: m* \7 r* j* m
  set grid-y-inc world-height / grid-size-y6 W% z/ ?3 |( q2 ?, p
3 m& ~% I% Y# \- A
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
! e* N; h$ r/ y" ^9 @* J- v: K  set acceleration 0.099
; x( b! w( K1 D( y+ N2 Iend( u/ R3 y  C7 x% O9 I: q

* S$ }& j# [9 t7 z8 |! O;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
. r3 g, `6 m3 \& k;; and initialize the traffic lights to one setting6 Q$ {% @8 i8 r1 ^
to setup-patches
% V- N  X5 b! S, k' g  ;; initialize the patch-owned variables and color the patches to a base-color
* Q# X% u9 t5 d$ T1 G* _, G  ask patches" K' Q+ n3 M5 s8 p
  [  B: e& N+ Y  h( a* i: M
    set intersection? false# ^+ N# |3 A+ c3 ^# @! }! L; ~6 ^
    set auto? false5 L; ~$ p! B9 Y8 z- R8 n
    set green-light-up? true
/ l7 e6 |0 f: f% ~    set my-row -1( r9 n0 [7 z; a) I4 D* N$ H( A
    set my-column -1
7 `, V+ M+ q! n8 [# K    set my-phase -11 x$ h3 F* S  k) \  ]
    set pcolor brown + 31 L" {  p; `# c  ?4 G1 P
  ]
' B4 t5 U, }0 x* s) X0 J
. Q* Q9 S* T0 x5 t  ;; initialize the global variables that hold patch agentsets; q5 u* s+ l  {+ X0 g
  set roads patches with
8 Y1 Z0 \5 w( t6 `( U$ X, [    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 G  @3 P- c( r! G# k
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ `6 ]7 q3 d1 o3 Z
  set intersections roads with
% K% ?5 r; b: P$ K4 e, _    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! s9 d# M( p) H. J- Q$ X& D
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 a4 {/ [( F- l2 V" t' [+ J
# j" e& j6 s! K$ M0 I. o% t
  ask roads [ set pcolor white ]
$ M: j8 S" Y" C" }) |* q. v5 X( U    setup-intersections7 l, U6 h# @9 T, V+ R% }5 e
end- d$ K* [+ `( ?6 M) k
其中定义道路的句子,如下所示,是什么意思啊?1 W# b- E) O) L3 i! n4 s' U/ z% x
set roads patches with( W& t7 `# ?1 O1 q
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: P, P% o5 U+ g* a( E4 V    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 A: o+ ?' L. `- i% Q/ i
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?
您需要登录后才可以回帖 登录 | 注册

本版积分规则

QQ|Archiver|手机版|SimulWay 道于仿真   

GMT+8, 2026-4-14 12:38 , Processed in 0.018844 second(s), 14 queries .

Powered by Discuz! X3.4 Licensed

© 2001-2017 Comsenz Inc.

快速回复 返回顶部 返回列表