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: 9255|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。5 j: R4 m( E3 u& v- Q! C
netlogo自带的social science--traffic grid这一例子当中,8 _: s" N0 d8 G% I
globals
9 ?0 H: d! T; y5 E- m: |[
( S$ Z7 i1 x9 `: e" l1 |  grid-x-inc               ;; the amount of patches in between two roads in the x direction
* @/ y) d* n& f: J  grid-y-inc               ;; the amount of patches in between two roads in the y direction
# G0 `+ w# b$ K+ ?5 d) J# K' Y3 M  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
4 U0 ?/ Z; g! W( j3 A6 l& \/ f+ b                           ;; it is to accelerate or decelerate
. J' f; y% Q+ x% {4 T  phase                    ;; keeps track of the phase$ E$ l2 v6 Q+ A# T
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure: s' I6 }! L% N- R2 {
  current-light            ;; the currently selected light' ^" B3 P* e6 x7 s3 G% B$ |
+ e. i# |  u: k/ C
  ;; patch agentsets
5 d0 W9 J7 t3 R3 V9 |) t  intersections ;; agentset containing the patches that are intersections
5 H; W# y0 h! i4 p  ]+ f  roads         ;; agentset containing the patches that are roads; I8 B& N5 I1 }& l
]8 M* E/ v  G0 g7 o* f
3 V4 L+ l5 S1 W" J/ u
turtles-own
: b7 v5 w  C; A! ][5 T1 i1 o/ n6 p  f- s
  speed     ;; the speed of the turtle
+ |- j4 H( c  v# @* N( A  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
3 ^' l1 x4 Z7 a0 q& l# R( Z% q  wait-time ;; the amount of time since the last time a turtle has moved2 B4 ~# x; M  B3 `& ^
]
' K+ }1 x+ a8 K9 u+ f
/ O3 Y/ ?9 X/ W9 C$ epatches-own& J6 `7 j2 E* {! K0 o$ @
[
$ a& O" H3 m8 [: i5 N  intersection?   ;; true if the patch is at the intersection of two roads+ P# M) _, [; n* T+ ~
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
( D7 b3 [; p$ v. `                  ;; false for a non-intersection patches./ l" n) d$ S% v+ y
  my-row          ;; the row of the intersection counting from the upper left corner of the
5 F1 w+ j3 d- N9 H                  ;; world.  -1 for non-intersection patches.4 [7 b  g% f8 Z/ v. v& O; `2 D
  my-column       ;; the column of the intersection counting from the upper left corner of the
5 z) S, x- u3 Q4 y                  ;; world.  -1 for non-intersection patches., u$ t4 ~3 W+ c& A. P9 a; O
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.$ ^, \' w: `4 a9 H
  auto?           ;; whether or not this intersection will switch automatically.
, k$ i1 e5 B7 Q7 c( r) H9 f4 B. _( u                  ;; false for non-intersection patches.  G! t& ~% c, N' r, |0 ]$ S
]
3 o# ]: p3 T4 ]0 P6 d& K
# r2 q" U* `' }( J7 [5 L8 X' W+ {- ~, @
;;;;;;;;;;;;;;;;;;;;;;* H* {/ E! X6 R- i
;; Setup Procedures ;;
) g, U) {5 L, C/ s! k! s4 B;;;;;;;;;;;;;;;;;;;;;;& M7 @( F. p' V: U  R

9 w& U, s; f$ }1 o6 B& X' ~; F1 Z;; Initialize the display by giving the global and patch variables initial values.
! V) W/ t7 e& {. |) Z( i;; Create num-cars of turtles if there are enough road patches for one turtle to- U% b& W1 i; d( Z8 S9 A. {7 _
;; be created per road patch. Set up the plots.
5 J, c2 J$ x  Z- p- r, @to setup
) [4 P# j$ _, t( x5 A* f9 {2 `, K0 A  ca/ P9 `- W0 ~8 p" f* [1 J7 N6 U
  setup-globals
/ {+ H. F5 A2 f- n0 v, k( Y0 Y' f, |* \; M! g* b
  ;; First we ask the patches to draw themselves and set up a few variables# i5 [1 i, @: I- u
  setup-patches
$ a% b6 Y" ~5 T; E: f  make-current one-of intersections2 J7 d+ |" \5 W+ n
  label-current+ ~" z8 r# W: [( `* U, F

/ `5 Z: R9 J" {  w+ M  set-default-shape turtles "car"
  s& F0 q% q% L  t" o7 u8 m' m2 }8 B
9 D* u- E6 R% Q! W" |! n  if (num-cars > count roads): T5 a! s$ a# n( v3 V' R% O
  [: Z2 z+ L4 j: _, x9 z: P! J. v+ o
    user-message (word "There are too many cars for the amount of "- p  v; o6 `& I* B) \2 ]* m
                       "road.  Either increase the amount of roads "
6 S, W4 [  N! I: o/ W. W                       "by increasing the GRID-SIZE-X or "4 B- H) s+ k" M! P0 t3 _
                       "GRID-SIZE-Y sliders, or decrease the "9 E+ v! ]2 C. X7 ~1 U8 E
                       "number of cars by lowering the NUMBER slider.\n"7 I$ x5 z0 [4 C: S/ K! ]2 U
                       "The setup has stopped.")
5 g4 p, }7 r% V    stop
& \4 u3 l4 G% n" r  ]( p/ `, ?2 l& S  _
! o3 \1 l; ~% {8 s
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
& @. }9 [6 K% k: [  crt num-cars! q. v5 Z2 j; u
  [! _8 f" s& c9 r* `
    setup-cars
! f4 o" q) r8 V    set-car-color5 d: X6 Y. W6 Z; n- s2 Q) n
    record-data
# B/ |9 Z/ W; c+ |9 t' d  ]
7 L" S8 h! Q" m1 e( v: U! j- T- h$ X: P0 w5 x  u9 n/ }  P
  ;; give the turtles an initial speed
4 p; u; Y& A4 A3 z) _" @  ask turtles [ set-car-speed ]% U  J& H. }+ K9 x+ a9 Q0 E6 P* Y

- i4 s% u  R) O9 V2 x/ Q  reset-ticks
6 z! l' i- ~/ q- F( }& v% Hend
8 j! h8 ]6 ?! [; I) ]/ V  J0 n" b5 V0 z6 C& l
;; Initialize the global variables to appropriate values
0 u6 w- x8 M' v1 T0 fto setup-globals
8 g) r3 a" `$ ~. J# p$ x  set current-light nobody ;; just for now, since there are no lights yet
1 l( @/ ^, t1 W. ~9 D; {, w# [  set phase 0+ b) P% z3 j8 e
  set num-cars-stopped 0
4 p5 E+ p5 f: x- p6 J) t  set grid-x-inc world-width / grid-size-x
* v7 |. }5 Q1 p. Z: p  set grid-y-inc world-height / grid-size-y
5 }/ G7 a( c! A6 v( X& i+ |) }* P9 ?% t3 @: w
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary' |6 D% l, p1 g+ t: a" W& q0 r
  set acceleration 0.099
$ Q' z$ {" M0 lend
) |" y3 i# l/ T& i6 U! f8 F- s$ l% L( o) p: s
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
  i! z7 i9 j# x- F' A1 c3 U+ m! ?, M;; and initialize the traffic lights to one setting
; m3 I/ n) W# G3 q; b! q7 c0 d( mto setup-patches
4 O0 {+ c5 ?: X9 g  ;; initialize the patch-owned variables and color the patches to a base-color
& o1 N! m- R3 U8 [5 r  ask patches( H7 B0 r) l6 @) f1 A* t) Q: {
  [
5 V; e$ H1 _) G9 e! A  q    set intersection? false
5 E% }) d$ i* W* Q7 P    set auto? false) u# `! H1 ~7 D* U& p( O
    set green-light-up? true
" q, h3 j$ j( V* ^8 C3 R* P    set my-row -16 T/ q+ p2 U) k
    set my-column -1
: ~' D& A0 v. Y$ Q' J+ I6 H5 w    set my-phase -1! A3 x. H2 b3 a1 P
    set pcolor brown + 3- m$ M3 C' R7 G; `' g: G. ^7 Q% D
  ]. s  _( l9 K7 p9 r
  n6 G: y( X9 V; y( |% u
  ;; initialize the global variables that hold patch agentsets( J; W4 H5 n' F4 r2 m1 a6 f7 m( i  r
  set roads patches with. M5 S9 |. k$ G4 n
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 g6 p, _6 Y7 ]# |* L( C) L1 c: v    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]) T3 S* r5 P! c, k$ Y
  set intersections roads with) g; L- P" E. s! K# `0 Y
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and+ n3 ~$ W$ ]6 ^, t, R4 G1 K# {
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 B; v4 M8 l' x; L0 s  Z- x% p2 k+ G4 y" o
  ask roads [ set pcolor white ]0 P' h5 [3 q9 y0 K0 P$ M+ [
    setup-intersections+ s) H' w7 g. A/ \
end+ P- m0 u8 j5 Q, K
其中定义道路的句子,如下所示,是什么意思啊?
9 W% c1 Z# O) G, { set roads patches with
. ~$ Z9 u/ J1 m" ]" h7 Q; E    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ }- J! l; d: \& P( A: L
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. u! P( u7 h9 Y2 s' m/ c
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, 2026-4-6 13:37 , Processed in 0.018405 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