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: 9480|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。
+ ^# ^; n  {! P4 J" m. lnetlogo自带的social science--traffic grid这一例子当中,0 d1 J2 @3 v6 T# o
globals
$ l. h5 b5 j# q; ]* _0 g[/ S' W# ]. e$ ^
  grid-x-inc               ;; the amount of patches in between two roads in the x direction3 q$ @; r% `  D. r' Z  O
  grid-y-inc               ;; the amount of patches in between two roads in the y direction% g1 H6 O, U# C8 j8 S6 q. E% |
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if3 t% I5 i3 \5 l( E" j8 d4 n- ~5 w5 H
                           ;; it is to accelerate or decelerate
3 m. ^0 C! `& o6 p  phase                    ;; keeps track of the phase
, u6 q: }2 ^* F' X' i  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
. v9 ^* m0 C( P0 m  current-light            ;; the currently selected light3 t: n, f, Q) z8 h: v' R
" I4 D0 D! O! N& v0 l
  ;; patch agentsets
& Q) T# a  @7 P  N  intersections ;; agentset containing the patches that are intersections
: ]0 G2 W) q- W# ]  roads         ;; agentset containing the patches that are roads
2 i" B! a. @  H7 n% B]
9 O2 T6 e$ s( h. M! B2 J6 U; x- u2 C7 K  Q8 ^
turtles-own1 L  C; n5 \5 C2 S; _0 w
[
4 l% N9 ~9 l% }9 l1 Q% D) R; @! ^  speed     ;; the speed of the turtle- {1 P  U0 }+ O. S
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right4 u9 W  \0 f9 P
  wait-time ;; the amount of time since the last time a turtle has moved0 w0 z7 V' r5 D: t+ S# `) B
]
% {) |, W2 [5 E$ A0 h! N* k* j# ?6 O$ P6 t2 P
patches-own
/ V1 O/ U2 `5 F5 i' f  Y: u[
+ [( `9 ^2 J" M  intersection?   ;; true if the patch is at the intersection of two roads
  ?! ]: c) p8 h  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
( X2 W9 ~  Z$ P0 n                  ;; false for a non-intersection patches.
6 q. M* I( E1 K. I$ ~1 ?# p  my-row          ;; the row of the intersection counting from the upper left corner of the
2 k$ w% e' E! R3 u# ?* p. F7 {                  ;; world.  -1 for non-intersection patches.
) C' @; U2 l/ z% U! d( n& U1 {- U( G  my-column       ;; the column of the intersection counting from the upper left corner of the/ Z) n/ w+ r( G: p
                  ;; world.  -1 for non-intersection patches." ?: V" r7 N) E5 Y$ Z' S+ \
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
, R: T3 v* Z& v1 S  ~) H  auto?           ;; whether or not this intersection will switch automatically.
* w# ?9 b. c' I1 i  V5 b                  ;; false for non-intersection patches.0 m# M9 W' P; s* A! t/ m
]3 x) ~# Q. R3 G* }" g" d

6 L* j0 Y8 D3 O- M$ M( ]% l" i
;;;;;;;;;;;;;;;;;;;;;;+ f3 }9 r9 }0 x! ]  n5 F# y
;; Setup Procedures ;;
' N, W& W' d2 Y;;;;;;;;;;;;;;;;;;;;;;
7 I% C* d! ?- {* f, z5 z& F
9 D# X# ^0 J, G( O& l7 E4 s;; Initialize the display by giving the global and patch variables initial values.- p* k7 j+ F! y
;; Create num-cars of turtles if there are enough road patches for one turtle to! W* ]9 ]5 f# V
;; be created per road patch. Set up the plots.3 t" [* o- e$ w
to setup, A! R# _* C6 Q1 q% d
  ca. [7 {9 j; {# n8 ?4 m( j2 M: Z
  setup-globals
( g8 }% s7 U1 K" E0 {% r
4 P: O  n: s7 R& A, S; Z  ;; First we ask the patches to draw themselves and set up a few variables
3 N4 A6 @6 g( L- d- w) n  setup-patches
. P% s$ {3 Z3 `& u4 O  make-current one-of intersections
; y8 J" ~8 t4 u( z" X7 ^0 _  K: t% C  label-current
- Q( o: r7 D% A8 v
- t. b" f' R' a0 ^  set-default-shape turtles "car"3 i! x# O% p8 Z. u) h. e
* d/ R9 T& I: Q
  if (num-cars > count roads)
1 b% w4 a# b& l5 f; Y* @  [
* ?2 h4 G( H: y+ p+ W9 r- I; p    user-message (word "There are too many cars for the amount of "/ ^4 _8 o. F1 P( B; |9 q9 N% \
                       "road.  Either increase the amount of roads "( ]" H4 F3 p9 V; C) g9 D& j
                       "by increasing the GRID-SIZE-X or "5 p5 S* d* _, h4 N" X
                       "GRID-SIZE-Y sliders, or decrease the "
, Y  A: U* G# R% Y, c                       "number of cars by lowering the NUMBER slider.\n"0 n: t( J! z! E6 L" @. I" Z; c/ U, x- C
                       "The setup has stopped.")
1 V& a" Y6 }' j" a4 F1 `( r+ o    stop) {" M1 ]! l, Y6 M, @* t# T
  ]
# p1 p/ `+ Y: q% Q% Q+ N3 f4 y) R$ f5 a2 h+ x, w" I4 ?
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color+ {' f& @3 a  ]; c
  crt num-cars
& X" ~1 U& {& w  [: |) I/ k6 a! T1 a0 s
    setup-cars+ {+ r  X1 u, B9 E! ^; C, I
    set-car-color
: }& {+ q2 v' j+ l    record-data4 D+ O( a" h6 z4 M1 b7 R  o
  ]
, x1 h$ f4 L- r" }$ y& o+ A2 ]
8 B- s* W' g+ K; q; a9 r  ;; give the turtles an initial speed
$ A; R% A% {. c; I  ask turtles [ set-car-speed ]
" p. [0 w3 A. x$ q2 s4 B$ [1 v
) I' t+ O0 U1 z4 }' Q  reset-ticks
% y3 t2 V; a8 ~* t' {! Kend  C$ ~% y. V% I  F6 z* C) i( t

6 K8 \7 I. @3 P! m4 X  A;; Initialize the global variables to appropriate values
8 E4 _6 f9 B% ]to setup-globals8 q" V( C5 h) u3 n
  set current-light nobody ;; just for now, since there are no lights yet
# A' X2 ?- g; G# K  set phase 0. U; P  {' ^" Q& A# @
  set num-cars-stopped 0$ ?5 z# V' Q8 B% d9 I6 X
  set grid-x-inc world-width / grid-size-x0 A- E8 W0 O4 l
  set grid-y-inc world-height / grid-size-y9 A" h/ ]5 d3 O5 e7 L. p2 B9 ?  }0 m
* e0 F7 s3 J2 v" M
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( u3 U" Z; A* P! S  set acceleration 0.099: x8 e7 L4 m: ]2 s2 M* f: h0 X
end5 M+ X8 k# w! l6 M( G3 n, x1 t

& }' u9 \6 l# _+ _;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& j4 S+ h8 m: A7 G  e;; and initialize the traffic lights to one setting
; I" u; ?) n  M9 ~to setup-patches
! p+ N0 n! H7 M& N' _) F" |5 N  ;; initialize the patch-owned variables and color the patches to a base-color/ _4 X$ O8 a( ?2 u
  ask patches
5 T3 X+ A+ ]* V2 W" M  [+ M( ~7 P; t; b
    set intersection? false( |4 P6 _3 k% |- J' T! ~
    set auto? false
5 o2 j1 u0 v, e( K* E+ w    set green-light-up? true
& ~" U' F% U3 |; z    set my-row -1! `8 S) W2 A7 T; `+ e  |" ?" U
    set my-column -1& y% ]( D  X5 }9 B
    set my-phase -1, A) q1 C9 I5 E. v6 {4 |! h
    set pcolor brown + 3: F/ i( p1 e2 l( I* b+ b
  ]
2 s2 V2 l% l+ C# W
' E# W/ E9 F7 X6 {7 {3 j' ]6 }3 b  ;; initialize the global variables that hold patch agentsets' N. I8 Y, T. N7 r; e: O
  set roads patches with% ?! X& Q. `* O3 \
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ E6 i( u- \) J0 K* R8 B9 `' F    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ g0 M; H" X: H: H( y  set intersections roads with
* [, c4 w5 [% x    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" J, X; N$ C6 D  u* H6 d    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]  i+ m5 X% r+ W1 M4 F0 u, Y

' D1 H# m9 Y2 [  ask roads [ set pcolor white ]
8 w5 P+ ~) N- k! h1 ?% R    setup-intersections# c0 Q2 T  ?! S. P; [) f6 {
end
8 J, ~+ k( I4 O: w8 c其中定义道路的句子,如下所示,是什么意思啊?
- G5 T* Q3 R; Z2 R8 } set roads patches with
7 X4 ~( J) H0 Z" J& ]4 N; X) K    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 O/ X1 P2 F8 i: ]* b
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" e' ?. \  [' H
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, 2026-4-17 05:24 , Processed in 0.014291 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