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: 9838|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。
; F$ P  E% [+ [# o$ m6 {netlogo自带的social science--traffic grid这一例子当中,9 K7 W/ N9 u3 y$ ?# p% g) v/ }
globals
9 Q! r4 @, }* ?, r4 H[& K% G: c$ S# G& Q) I
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
1 K& `# Z* l. i  grid-y-inc               ;; the amount of patches in between two roads in the y direction
3 Z4 f4 }( w4 l/ n, @" r" g  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
$ n3 g% ^, p4 `) B6 U2 `                           ;; it is to accelerate or decelerate3 }( a1 {" }6 ?/ P) j* g
  phase                    ;; keeps track of the phase
/ G0 _. n$ Y) r  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
, B; e3 `4 N9 ~& {5 f0 q# i  current-light            ;; the currently selected light2 Q8 Y0 D! C9 z4 s7 |
4 O* G# ~( M5 L, A: b0 C
  ;; patch agentsets
% J2 i+ F5 ?; X% w3 k1 }/ w  intersections ;; agentset containing the patches that are intersections4 N; @& ~/ K# @: w  v. z
  roads         ;; agentset containing the patches that are roads
2 o6 C. ~( _6 \! S]' d: E+ M, C: o( l0 \$ M
# m  e' ^! |1 T1 E
turtles-own( |" t) o# `' l  j+ D
[
1 z8 x3 o+ o9 j( c* h' e3 k8 ?) F  speed     ;; the speed of the turtle
5 \1 J2 k& k5 c& s  up-car?   ;; true if the turtle moves downwards and false if it moves to the right: H; k8 @* D8 @, _- A% e2 V
  wait-time ;; the amount of time since the last time a turtle has moved! {. R! l; {, y, H" A8 o
]4 p# \6 w- {0 `& {
3 {* _/ r# i+ s
patches-own6 d5 T; y* `: z: ~! o
[* T9 Q" I) ^/ _
  intersection?   ;; true if the patch is at the intersection of two roads8 D$ z! H$ R  P) C  k1 E
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
1 Y+ J# H7 a8 Z# G6 P# b                  ;; false for a non-intersection patches.
% I. Y- V0 K; {9 m0 R3 C! i  my-row          ;; the row of the intersection counting from the upper left corner of the
5 s5 w$ R: R+ R2 T                  ;; world.  -1 for non-intersection patches.% C. L9 M' e2 v( ]4 B
  my-column       ;; the column of the intersection counting from the upper left corner of the
. _1 V" _6 m) [3 O  S                  ;; world.  -1 for non-intersection patches.
% @- ?# [% C3 A. t6 T5 Q  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches./ a9 n# J. A9 k9 F& o
  auto?           ;; whether or not this intersection will switch automatically.
- Y, c  W7 B, d* R5 y" t                  ;; false for non-intersection patches.
8 m( n1 c0 Q7 ^; y5 M]1 V9 T9 ?2 \- v
' g! _6 |  f) ^' C  \  S% m, V$ Y% r

7 b( T2 H+ m& @6 L0 O;;;;;;;;;;;;;;;;;;;;;;
# M4 O" B3 Q. `! ?;; Setup Procedures ;;8 X8 t& R7 W% {( C
;;;;;;;;;;;;;;;;;;;;;;
) d: a. ~' o  H7 c& |# m8 n1 ]* U2 ]/ ~7 C8 B  j2 d' F. H
;; Initialize the display by giving the global and patch variables initial values.
! H: u+ D! h6 Q3 _, o. u# R2 v;; Create num-cars of turtles if there are enough road patches for one turtle to# L; v' m+ ~( Q
;; be created per road patch. Set up the plots.
6 g% I' ?0 d- W6 Q$ c) B9 c8 ~( _7 Hto setup
" ^; w. a5 W5 |" H5 h  ca
3 J" q. q3 T  X5 N  setup-globals/ k3 B# o' }) c7 b0 x

9 ~7 }3 C3 {" @' Q  ;; First we ask the patches to draw themselves and set up a few variables
# b) P. z2 f6 Z% c, a' S" s) ?  setup-patches5 G  }& H0 F( n5 l! n! Z
  make-current one-of intersections
: C6 R% }" s* H# U" U. \' ~; @  label-current
3 t4 t5 Z! E- z4 T& [9 o( _* q  D; `( t
  set-default-shape turtles "car"2 y6 _6 P( i7 T$ {9 K! V+ `6 K
* G% T5 \2 P* a: S9 R
  if (num-cars > count roads)2 W) A) N- z# n# N  V* f: ^. \. S3 k
  [2 C% a2 X* @4 H. \+ h+ T
    user-message (word "There are too many cars for the amount of "0 v) w: T- Q) {, ~% F
                       "road.  Either increase the amount of roads "
6 D& h; I2 n# o  I" D                       "by increasing the GRID-SIZE-X or "
: ^3 m" b1 f" O1 O! b8 ~2 M; L( R6 w                       "GRID-SIZE-Y sliders, or decrease the "
- }# U) x/ d. {1 m$ Q                       "number of cars by lowering the NUMBER slider.\n"/ P. a! O; D0 t: X8 \
                       "The setup has stopped.")
6 p) L2 T% C' W    stop& f2 H7 C) P9 s, A
  ]
! G+ Q& x/ e! m. B( B  E3 J; I
% p  Z6 T8 {1 V: O0 x  }  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color) w) P# Q5 q, \8 M
  crt num-cars
- X, S* i$ a+ P( N  [) ?2 ~8 p) Y( R0 \) x
    setup-cars% b; v* H2 y4 t, i0 n
    set-car-color' u6 q7 _- Y* T1 Z6 r& x) V
    record-data; C* f' m, b# F7 c7 z# M
  ]& E' g; {- S7 X- a

5 H& f4 F2 T. i* i+ Q! H: L4 Z  ;; give the turtles an initial speed
( k, t9 k0 X3 W0 a4 Y7 Y6 l  ask turtles [ set-car-speed ]
; z8 p; g; @( \% r
2 l; \7 s. V: m! b( X9 z/ @  reset-ticks% a% R2 i. q/ }7 y% J" r
end
8 u' K9 `! d# B+ M
4 \4 X4 ]; _/ X;; Initialize the global variables to appropriate values$ W; {) i# O4 q4 [& d
to setup-globals
9 ?+ M1 c# z$ `( l& Y  i+ j) V  set current-light nobody ;; just for now, since there are no lights yet
; C" x7 ]1 R) d; n! Y& |2 l# o  set phase 0
& W1 N" j( D+ A* u1 a  set num-cars-stopped 04 n$ y* B/ S4 k  }& ^
  set grid-x-inc world-width / grid-size-x: d1 |; \+ t+ T" d. s
  set grid-y-inc world-height / grid-size-y
: X- ~7 f0 l- x2 E- [% @" r" I: C4 j) t4 Z& g2 h
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
1 a+ L. r& C, ^2 W  set acceleration 0.099
8 o9 y$ [  d1 ]# [  B( B4 K7 q4 Eend
3 S7 n3 x3 `; x6 X1 R0 R/ N
0 _$ U9 A8 ?; }9 A+ Q' q! ]% O;; Make the patches have appropriate colors, set up the roads and intersections agentsets,  X1 ], X& W" }# D" X1 e# P
;; and initialize the traffic lights to one setting
% k! j% z) H# Kto setup-patches
$ u! ~+ }4 D: S8 N$ L; n  ;; initialize the patch-owned variables and color the patches to a base-color- x( B- C5 L% f. R  x, y
  ask patches
; a5 r! V. U* n! L  [8 H* ?4 z5 u0 L) j: a, e
    set intersection? false) g* I% `" ?8 Z9 ?- A9 b7 D
    set auto? false: ^* |8 k' t" O9 T
    set green-light-up? true1 u: K- H! j8 A3 o
    set my-row -1
3 k4 [: M0 M& M- K0 _: l: N    set my-column -1* u( k- R; l# r7 h
    set my-phase -13 T) h4 J9 s& D0 V* i
    set pcolor brown + 31 f- o$ z& J& t$ S( s$ \
  ]
8 a+ `2 r) }& o9 S# N
8 b0 u! u8 S+ }. G, f+ d  ;; initialize the global variables that hold patch agentsets! Y7 Q" a4 p( Z$ f' L3 y* E0 g
  set roads patches with; g; [' P6 F3 c' Q& v% I
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 ~4 H) K+ ]% S9 E/ L; H
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 [; s. c. u2 W0 K# Q/ O4 @* }3 K% C  set intersections roads with0 p7 b( a6 ~3 Z! v
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, u9 l5 ?* W) {* e7 O5 @( |# n    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# p4 B( F3 E; V; |# t8 U2 w

# N( v0 c( R2 ?8 v7 Y5 j: O  ask roads [ set pcolor white ]. ]2 z! Q$ N5 z' V: G& H
    setup-intersections3 ~3 D+ @% Y1 S# i
end! V( O: T3 l4 Y( Q% S# K
其中定义道路的句子,如下所示,是什么意思啊?+ s* p$ ]& b: o% ~$ r
set roads patches with2 x' m$ f& w( K+ Y+ J5 B/ f; d  n
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 n' k& u& z- c! U
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 F# q  e" \/ |$ ^7 @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, 2026-5-3 02:50 , Processed in 0.018895 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