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: 9379|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。9 u2 Q. Z# ~/ c
netlogo自带的social science--traffic grid这一例子当中,  R! m  H- d' c4 H7 V+ u
globals
! u& J$ Q2 T: `! U1 y- o6 h[
) T9 `2 }. R) j& x( V  grid-x-inc               ;; the amount of patches in between two roads in the x direction3 C% d4 u, d& c
  grid-y-inc               ;; the amount of patches in between two roads in the y direction' }0 Z2 m. t* |' l( _8 O. Q
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if8 ?$ V/ w1 c+ T6 ^2 Q
                           ;; it is to accelerate or decelerate5 h* B$ V4 e1 o$ Y1 ^! w
  phase                    ;; keeps track of the phase
- b+ s/ E8 P' b  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure& a' a  l; o" h! d
  current-light            ;; the currently selected light: b3 [) z0 b! y' J1 y2 S. I

, Q1 D3 ~9 w3 ]3 c* Z, T" _: ^  ;; patch agentsets
5 ?# ]! L3 r+ z# I  intersections ;; agentset containing the patches that are intersections2 [- F+ K+ P( v! L8 b# G
  roads         ;; agentset containing the patches that are roads
+ s0 {; T6 k! s7 }, y3 I1 a4 M]
; U) m1 Y, M7 R5 U9 Q# I: Q# Z* ~+ x" B9 I, s
turtles-own, O& s6 j( q; z) ?5 V( G
[
. B( p2 O- p# q$ M  speed     ;; the speed of the turtle! T' h7 s3 o$ ]9 @. O0 ]8 L+ P. M
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
  M6 F2 T2 R' z. D  wait-time ;; the amount of time since the last time a turtle has moved- P+ |6 H: p. Z; \
]* T: @$ Y. ^  R, ?& u
) y  }/ Y' m  d% A
patches-own
+ E0 s0 |3 R1 w[( v% l, B* c/ g) R. D9 Y: O/ H- [- X
  intersection?   ;; true if the patch is at the intersection of two roads
, \, Z' l/ W. _9 ?1 W  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
0 T1 \" P) u- j" N# Y  f0 s                  ;; false for a non-intersection patches.: G, G2 i* H8 D8 C: R0 y0 l
  my-row          ;; the row of the intersection counting from the upper left corner of the( K  K) V( N! \0 }: ^; i
                  ;; world.  -1 for non-intersection patches.
+ m3 K# v- n' e  my-column       ;; the column of the intersection counting from the upper left corner of the
7 }# r5 b# ]/ L; ^! v4 _- z+ D                  ;; world.  -1 for non-intersection patches.
7 u. o" p' n+ ~; a5 X( o" s  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
3 `5 e" @' Y) T$ h" j' b  auto?           ;; whether or not this intersection will switch automatically.
0 O8 d  r4 E! n: i7 U                  ;; false for non-intersection patches., W( L+ W; I* i! K) n* j* l
]" p# `2 ?* X) l* M

5 b" A/ O* F. a, u' o: C
6 P/ ~: Z. [8 r5 V& K( ?, T;;;;;;;;;;;;;;;;;;;;;;
2 H3 ^& i* t& n. z3 a;; Setup Procedures ;;
% L1 d% U& T3 n9 l( _% j;;;;;;;;;;;;;;;;;;;;;;
$ t( V* E' d( G7 m
7 J* Q& ~! Z4 f4 b3 @$ L/ x" m;; Initialize the display by giving the global and patch variables initial values.
# H9 L( v5 |9 [5 Y) x' [% e; L;; Create num-cars of turtles if there are enough road patches for one turtle to2 q0 z5 i! g  Y/ |- X, e
;; be created per road patch. Set up the plots.1 z$ i5 x: |& ~( ?; \# k: ^
to setup
' x' O5 T# t! H( t6 x  ca& R% s2 m- L/ `% B
  setup-globals
" F# p* J: ?: V" J5 P$ z( _9 @9 r0 O3 q+ l0 _, T- q5 t
  ;; First we ask the patches to draw themselves and set up a few variables
* W& }* w7 w1 c4 Z  O( q" l  setup-patches7 N2 y: m0 F  Q$ m& c
  make-current one-of intersections% u4 z9 X7 A/ K- @( c
  label-current
+ c& V. Q) T* f3 r
' L" A$ r+ ?- R. X/ `. E$ P  set-default-shape turtles "car"
- `) h: t- o0 F: k9 B8 C+ B6 F1 X0 Y% p  {4 A( ^8 v
  if (num-cars > count roads)1 [8 {3 s5 V' Y: L
  [7 u) G' S; L$ ]) x* N7 v2 Y
    user-message (word "There are too many cars for the amount of "
0 s0 y$ {- @  ~+ [# {7 h8 t; C* z                       "road.  Either increase the amount of roads "
' n1 I' y, J8 q                       "by increasing the GRID-SIZE-X or "
8 T' U' L8 {- G& d+ ]3 Y0 S                       "GRID-SIZE-Y sliders, or decrease the "
/ ?# L9 Z  _$ x$ Y* P9 y' X9 P                       "number of cars by lowering the NUMBER slider.\n"
9 W, I: ^; M- c& d# E& x4 F                       "The setup has stopped.")* K8 d' ~- ]2 O' ~- ~& f. H
    stop; C0 j' {( F; j
  ]
6 l: E$ f+ G! j$ A3 H" Q3 s
- E; A) `' j# S: _& \7 s4 E  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
- m3 x! a7 |; ~5 i4 a- |  crt num-cars
" {% @$ Y6 p" g$ o, T: L  [
0 s6 C3 T3 L9 `$ u6 |7 y$ G: F$ z1 `    setup-cars% ?  I. T$ e% h1 G* ^9 t2 H
    set-car-color
  e# ~( v/ q1 |4 h, [$ Y    record-data! w( t: G  [9 r* ^2 J
  ]# D3 T/ s/ d$ X
% v) T$ @& t+ P* |" S
  ;; give the turtles an initial speed5 m; V; ~( O0 G/ j- |
  ask turtles [ set-car-speed ]
% h: W' I6 `: `- o& \% o  P, V% ?
4 B, j/ P( U5 A0 E: n  reset-ticks: z% ?! l4 p' D4 p6 @, B6 D
end8 t! F$ {- I3 s: \8 ]3 ]

' a7 u4 r, I% @5 T) G3 B. `% ?  g' h" f;; Initialize the global variables to appropriate values
2 {3 m1 t7 h* Y- n$ d# uto setup-globals0 G& v4 H8 \* m+ d( B; B
  set current-light nobody ;; just for now, since there are no lights yet
$ k6 ?8 `6 @+ g  C+ z  set phase 0
5 H! ^3 Z2 t+ v  R- I- d# |! [' r  set num-cars-stopped 0
' [/ M. U4 ~7 y2 g/ g  set grid-x-inc world-width / grid-size-x4 g" K+ j5 L5 d& x7 k4 h6 ~
  set grid-y-inc world-height / grid-size-y. u% }5 I* P+ p( F! m

* A6 p+ i* {# l4 K  `  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
/ z1 ~) e4 J4 G" k  J  set acceleration 0.099( t) ^( N4 D- Z
end4 z5 I# I1 {) Z+ D5 G) v2 n) T$ F
- m5 ], `- w# v- l7 t- B) D
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,, ~1 G0 k! k* k# T
;; and initialize the traffic lights to one setting& o; |& w. C1 n7 c
to setup-patches
) b* m$ |7 a3 ]0 M! C9 D# y  ;; initialize the patch-owned variables and color the patches to a base-color
/ K% B  ?4 ^0 \" U  r4 l6 A  ask patches
: D  B3 E8 y2 G- N% k- @  [
% V* r6 u; H; X3 j$ P9 l    set intersection? false
+ V) J, o: X) y. w& U    set auto? false  H; F& P4 K3 x2 o. X& T6 D
    set green-light-up? true
; t$ P. C4 }: T8 Y( k4 T- A) U    set my-row -1! U/ t1 l4 ^( n* [2 v
    set my-column -1
! W1 W% w9 I9 r1 N2 x    set my-phase -1% q0 V! E/ x5 y; C0 ?; p2 j
    set pcolor brown + 3
( e, S! w) x* X: a: a  ], B& m3 {9 B8 U0 H% J4 G% E' Y6 ?; ]

; X! X1 ]5 I5 k  ;; initialize the global variables that hold patch agentsets
% ]4 I% Z5 k% @/ u) L2 p  set roads patches with
/ c& e, G4 c; }7 |/ d, ]) R    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ R* i' O% `" [1 P2 S+ y    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
( q1 p6 E4 o, X5 Q  set intersections roads with# M+ \3 c8 r- G* v
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and% \  O& Z/ H0 P% L$ \
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 I- B1 L5 \- R5 T+ A

; q9 \# r  L0 Z  E9 R  ask roads [ set pcolor white ]2 F0 Y' I# O4 w/ @7 M
    setup-intersections
- ]" R4 K0 b& Qend
, r7 K5 s+ Y% S其中定义道路的句子,如下所示,是什么意思啊?- M5 ]' c6 \; K! `0 p: |$ i
set roads patches with# v; ?; V7 W6 O1 w6 i" z
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 K' f7 r; C) S4 h$ X" S    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 _* x5 |1 h- {5 @6 \# K4 y& D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, 2026-4-12 17:16 , Processed in 0.027733 second(s), 15 queries .

Powered by Discuz! X3.4 Licensed

© 2001-2017 Comsenz Inc.

快速回复 返回顶部 返回列表