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: 11273|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. z6 \/ B' X' q$ I6 j9 p
netlogo自带的social science--traffic grid这一例子当中,, g2 ^- c" `) X5 K+ |) \' j
globals
) b1 O' e1 m, G, r6 A: ]' o7 m5 q[. b0 m# _1 J, A: x4 I3 f
  grid-x-inc               ;; the amount of patches in between two roads in the x direction7 Z6 ^) a: P5 V' Z& z1 X
  grid-y-inc               ;; the amount of patches in between two roads in the y direction
+ c) d/ W' J' i' H  acceleration             ;; the constant that controls how much a car speeds up or slows down by if" l. g: t4 r5 D$ a) W' Z  L
                           ;; it is to accelerate or decelerate
+ R+ R" P' b9 A0 z' _  phase                    ;; keeps track of the phase- s, L4 x: i2 ?
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
$ z. F$ G' Z# Q& P0 d8 @' a2 i  current-light            ;; the currently selected light5 O/ }$ [, H  n2 J* Z/ p( b

+ ~4 d1 G* p1 b0 h- R  ;; patch agentsets1 j' b4 R" E$ l1 ]
  intersections ;; agentset containing the patches that are intersections6 j' w, T0 X/ _% M& c2 J; q, ]+ X1 u
  roads         ;; agentset containing the patches that are roads
3 Z# E  N- a5 e: U]- l/ T+ m6 K4 Q! w# m7 ?

% j7 X( R! G; I$ z9 v% b% L! aturtles-own% i: d2 I, l$ e2 Z- _5 p* x
[" V# ]* B, P8 f$ T2 ?" ~# E
  speed     ;; the speed of the turtle
' U: W: @( H. |6 L# S* G! p/ D  up-car?   ;; true if the turtle moves downwards and false if it moves to the right- X0 b: H7 |# ]' \. o% F
  wait-time ;; the amount of time since the last time a turtle has moved, c! v4 }9 ~6 o
]1 X) u% }  H$ ]: w$ O8 o
7 r  t$ I5 r" v$ F5 b
patches-own  H, h7 f: R9 j5 @+ i% t1 a
[
" e6 |' z6 f8 G8 u  intersection?   ;; true if the patch is at the intersection of two roads
5 f: G0 x7 ?; g& Y  green-light-up? ;; true if the green light is above the intersection.  otherwise, false./ L/ w9 _) u9 B" U: G+ P
                  ;; false for a non-intersection patches., m1 T4 i1 {) Q' ]. b
  my-row          ;; the row of the intersection counting from the upper left corner of the
- G! I' a1 R, e  t  g* K; m0 h5 X                  ;; world.  -1 for non-intersection patches.
- I4 T/ V; P. b# F/ M( m1 v& Z  my-column       ;; the column of the intersection counting from the upper left corner of the. V' M( o, N0 [
                  ;; world.  -1 for non-intersection patches.- f: m; z. d+ ~! P0 f# L' f0 E( F6 ?
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
' ~3 J+ U) D% |4 w6 A  auto?           ;; whether or not this intersection will switch automatically.
8 p# I( M+ i& \& D& J                  ;; false for non-intersection patches.
& T0 V" m. U) N( O0 B! z+ q3 ^  o/ v# []' K' e" A. S* [) ^. g( c2 z
. h- `) A$ q6 w0 g/ g

% I9 p" p3 U% `;;;;;;;;;;;;;;;;;;;;;;
$ M. k$ Q" u8 j( V; Z+ n;; Setup Procedures ;;
" C, ~1 q9 y0 T' d0 b;;;;;;;;;;;;;;;;;;;;;;
5 |' z* i3 v; W9 I4 M
" M6 ]* L2 v  I* S- m3 U;; Initialize the display by giving the global and patch variables initial values.
( y  ?# j7 d2 P;; Create num-cars of turtles if there are enough road patches for one turtle to4 ]1 e, s$ C0 c4 m" X* q; \
;; be created per road patch. Set up the plots.
. b! b' G, [( Q7 I8 n! dto setup
- p" c0 Y* d6 U% E! p  ca( R5 x$ i4 _, S5 ?; W
  setup-globals
4 M2 Z. E9 ~! R9 |  G% q5 T
4 u+ L$ P2 P+ N& |, c. ?+ T  ;; First we ask the patches to draw themselves and set up a few variables6 H, a( b! h  O7 z, H5 a
  setup-patches, d' G- F7 K& Y" D7 t0 V
  make-current one-of intersections
' p; R) Z" ]6 O* i! h' r  label-current6 x* w+ C4 o1 j/ Y, k3 y" g

0 v% [: v% _* o7 m" B  set-default-shape turtles "car"
- h; ~7 M5 S) o
3 J3 Y+ i" x) L) \8 k( }  if (num-cars > count roads)
2 L  j' s  m8 u/ Z  [" G9 _5 P) p  @5 b
    user-message (word "There are too many cars for the amount of "3 y# F( x1 z/ F; i  k
                       "road.  Either increase the amount of roads "
7 I0 P. ~# x$ V& s                       "by increasing the GRID-SIZE-X or "2 u. `" B7 c9 Q4 d7 [; a
                       "GRID-SIZE-Y sliders, or decrease the "
7 R+ _8 Z1 B0 F( h2 l$ Z1 P                       "number of cars by lowering the NUMBER slider.\n"4 \, y7 n( _, v3 k' `1 P( ]; G8 u
                       "The setup has stopped.")
! U1 B7 `4 M% D" \( y    stop
& U+ m4 R  q( K3 x& Z  ]
. C$ w+ N4 r& ^- f# L- |
4 f- n. m  ?1 Q6 G$ K7 h. `  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
5 N; ?9 X) @/ n3 G' e- J  crt num-cars
) S$ ]2 Q0 Q4 [" S  [
/ i$ X7 X9 [6 G% O    setup-cars
. b0 X3 J9 _0 I% [    set-car-color
- c8 b. B  _" c# k/ P    record-data# x7 A# G+ v8 c% H3 t. T
  ]: {6 t9 L) [7 T* y* X

( p# E& ~7 j* p  ;; give the turtles an initial speed" X0 Y1 s. ~5 ^* n" t
  ask turtles [ set-car-speed ]
- ~/ S) X4 m0 k& J. M
- ~4 b' c! \# E2 I: M! y& z  reset-ticks/ y. Z  y; h4 C5 ?( ?) y* a
end
2 [8 k! Y# D0 C$ Q- ^
% v6 r. Y. r6 \; t% m9 R;; Initialize the global variables to appropriate values
7 G8 F6 r" G' G- fto setup-globals
3 |, R0 \1 H. [3 q  set current-light nobody ;; just for now, since there are no lights yet' o0 M& o( Y' s1 Z  Q3 v
  set phase 0
( @1 f' N: g2 }3 B  set num-cars-stopped 0
" n7 N- M" }! y* \5 Z4 b% N  set grid-x-inc world-width / grid-size-x
2 i5 m7 N& C5 U( [  set grid-y-inc world-height / grid-size-y
$ o# \) ?6 K8 X. w5 E' a% X, C1 f3 ?( i' L7 m
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary+ v$ d& V* I: d# ?: }5 M
  set acceleration 0.099; |1 ^0 Q1 a: K" o1 L- o; k, }
end
9 U5 m8 v1 R! P4 p4 i- k  @' u! A) v# n
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
( h( X# @/ H+ K# V5 q1 S) ]) b;; and initialize the traffic lights to one setting
! |1 v) z% R! R, `  O' y& Bto setup-patches; L( M# e* E9 d7 V1 \' E
  ;; initialize the patch-owned variables and color the patches to a base-color8 f6 X. f2 ~: ]6 [- T* n7 n
  ask patches
- e7 B# ?& B8 j9 i1 b2 {  [5 L2 q+ p  n, y% _8 P
    set intersection? false
; R4 G2 z4 Y* `7 E    set auto? false6 q3 T( b0 s2 a- Z
    set green-light-up? true
9 r# k" K" k" w    set my-row -1
6 b1 G; e+ X1 s- |4 ]  o    set my-column -1
8 ]' @4 a, |* ?  d5 ^$ L    set my-phase -13 p% W+ |" m. s5 ^3 L' d9 V
    set pcolor brown + 3* }1 t0 b7 L8 Y, o  l& G2 j
  ]
4 X2 h, p; x; T
) W' g: g% Y0 C; n  ;; initialize the global variables that hold patch agentsets
" z8 x# J3 A3 [9 }: y, C  set roads patches with3 t4 V+ d3 z& N, m& q2 K0 E, q# e
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ ?7 ^$ b2 ~; B6 F6 c8 Q3 @9 r8 {    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 |9 q5 u& l2 B& M  set intersections roads with
" C) A8 u: h' l3 @) q    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and7 Q, y: r$ @+ M7 m" }
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 v$ B! ?. \" s% r5 y, d; a

; U* ^: e& D; N  Q; H, [$ n  ask roads [ set pcolor white ]4 C0 t: R* |' m1 B7 b; a
    setup-intersections: z- x1 B: `0 o) S* v
end5 W. o: S6 k  h
其中定义道路的句子,如下所示,是什么意思啊?  `3 f8 h, ?" d$ {/ `! Y% v- J' r
set roads patches with
( {3 X) j% c4 o( p    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, D" m0 i. i4 y0 T' d
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# n" ^% o7 c. b' _4 I' Z2 ]0 V
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, 2026-7-22 23:36 , Processed in 0.019387 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