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: 10251|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。: x) Q* I( a! @: `
netlogo自带的social science--traffic grid这一例子当中,
' m' H* O7 J! ?+ @, eglobals+ a  R! E( b0 w# \  e4 J
[
  a# S% I1 {+ G5 E  grid-x-inc               ;; the amount of patches in between two roads in the x direction
: Y. \% \! I# L+ V+ y# h  grid-y-inc               ;; the amount of patches in between two roads in the y direction5 l' X; M3 u% k( _9 ]
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if. J* Y, R9 |, t* O! I* R
                           ;; it is to accelerate or decelerate& p# i; p' h4 B' \6 s0 n
  phase                    ;; keeps track of the phase) r6 y3 F  o! q3 I1 f* Q
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
$ ]! q; q# [+ z/ F1 z  current-light            ;; the currently selected light
% P6 R) ~' W2 }3 Y" b' m! |" W) Q+ O/ l
  ;; patch agentsets
( H: W% s- e- Y; g7 M5 T  intersections ;; agentset containing the patches that are intersections+ E. b- d$ v4 H5 r9 |* K1 b
  roads         ;; agentset containing the patches that are roads2 E1 Y  y: O! A: W( j) }
]& t4 {+ C; c3 ]5 Q# L' S- D4 N" Q

  T+ e" v2 B" t$ x6 Nturtles-own  X9 \) W! h; I: e: ]
[
& q1 R1 B$ B7 ~2 ?, O. E2 \  speed     ;; the speed of the turtle$ M8 M. @7 p4 S; I9 u
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right" U: B$ C, N7 `, I+ ]0 c
  wait-time ;; the amount of time since the last time a turtle has moved' S( x# p7 W. ^  n
]
: d3 \0 g% x  O! k* k( W
' K; \9 q8 F7 [; N) apatches-own
6 j; Z$ z1 t" ~0 ~[
8 h  C+ D# f  [  intersection?   ;; true if the patch is at the intersection of two roads
* ?3 K+ t: P; Z# t0 q4 u8 g2 T& p3 X  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
- |; }  x/ Z8 r3 L' G                  ;; false for a non-intersection patches.
; M9 |1 t! f' |7 F& S8 F% ]. t  my-row          ;; the row of the intersection counting from the upper left corner of the1 _1 d5 o& g2 r  o+ o$ Y
                  ;; world.  -1 for non-intersection patches.# Z- S% u5 S: K0 e2 E1 E0 P: S
  my-column       ;; the column of the intersection counting from the upper left corner of the
# p8 s! i6 n5 i; D                  ;; world.  -1 for non-intersection patches.
' j$ I' H; ?3 S3 i  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
' c9 P9 p8 }7 [, A  auto?           ;; whether or not this intersection will switch automatically.2 C; l5 W" X' A9 ]* I& m
                  ;; false for non-intersection patches.* j# `+ Y; |0 B' [& }2 j: E; S% D/ g
]7 Q  \  F, P/ M. D, Q4 I( O
% j0 Y1 p' r0 A

6 H6 H8 Z4 i9 v  Y1 {( t$ y;;;;;;;;;;;;;;;;;;;;;;
; q; ?. @# W5 G6 X0 ^) _;; Setup Procedures ;;7 L9 _( P$ c* {+ O+ \: E5 W
;;;;;;;;;;;;;;;;;;;;;;2 Q3 W; Q# z, O* K. h, G2 {

' w# i) E% y; k9 k" Z;; Initialize the display by giving the global and patch variables initial values.* U0 {3 E1 t8 L5 ~
;; Create num-cars of turtles if there are enough road patches for one turtle to
5 C9 H0 P5 \; R3 y+ k# C% m;; be created per road patch. Set up the plots.
( [  g5 @  x/ L9 q; G6 ^to setup. H& g7 I$ B, o8 i% @& [% F
  ca
  `9 i) `7 [3 F" U6 H  setup-globals, C0 V& [6 H# Y8 h2 E( N$ M; C7 _! F

0 K6 }- T! r9 f  ;; First we ask the patches to draw themselves and set up a few variables. R( g$ M, K; x' W3 ?
  setup-patches
9 Y3 o3 Y+ q) A2 x$ F8 S  make-current one-of intersections: l$ c- D! |  Q  f( t& h
  label-current# H7 G$ H/ c, U% m
4 N% C9 F/ U. B! ?" b
  set-default-shape turtles "car"( C+ A7 Z* s6 i4 x

7 Q6 {1 M5 {; J4 |+ Q  if (num-cars > count roads)
8 w% `9 @8 K; x6 W2 O) s  [, V  G4 A7 S4 r' q5 C% |7 S
    user-message (word "There are too many cars for the amount of "
9 v5 A+ H5 B8 G: |* s: ^; P                       "road.  Either increase the amount of roads "6 b0 B0 ~1 l5 p/ R$ _
                       "by increasing the GRID-SIZE-X or ": h9 {! Q1 B* t$ S
                       "GRID-SIZE-Y sliders, or decrease the "6 O3 g; R! U* B7 }. n  }8 N; B! H
                       "number of cars by lowering the NUMBER slider.\n"
7 ]  K3 o+ B, {2 ]0 q, c0 }                       "The setup has stopped.")4 C1 h2 i9 q3 S2 B
    stop8 c: B) A3 s( [
  ]% H( M+ t8 I* p2 ]

. Z+ O' u3 J) G) N% W  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color6 V; a; z  r! m( E
  crt num-cars3 T$ L9 h( g+ \$ Y, W$ O
  [8 F5 ~  t: k* E4 `7 ~
    setup-cars
) ?: M& J6 S7 O: u/ O% r, X    set-car-color
+ N" n1 A  a2 @3 b- n  w4 r    record-data
2 W! _+ o& x- u. ^2 s  ]0 Y0 n9 z3 c( s
2 n$ Z# `- f9 E8 ], I
  ;; give the turtles an initial speed& P7 T& o) O: o# ]" ^& z
  ask turtles [ set-car-speed ]
, I; I6 E" d# P) u0 J2 Y$ L5 t7 C& T3 O$ P; R* f! z& v* Q1 O3 x. l' Q
  reset-ticks0 U3 ~7 ]+ V0 t/ ]
end, E' @3 P# I" C" x  b
+ |: R' s5 \' q- a; q
;; Initialize the global variables to appropriate values
! C6 P- }) `- h3 J& q$ e2 vto setup-globals) D2 Y3 C% E  x+ D  u7 M
  set current-light nobody ;; just for now, since there are no lights yet! x& P5 I% N9 N
  set phase 0$ D% L2 G, o- o+ w" L6 B; g; y
  set num-cars-stopped 0' f" N. b* J+ Q4 M
  set grid-x-inc world-width / grid-size-x
4 x% [- w  z( F( i: o. v  set grid-y-inc world-height / grid-size-y( ]3 A: b/ M  L  J1 }

6 i$ l. C# l; k2 R' I  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 D6 D) O" o% z- z" [* A
  set acceleration 0.099
/ H9 L9 Q6 B, C/ K( U! I2 ~1 L7 gend
) X1 ^0 Q/ W- S- ~$ s- y) M9 r9 `
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,, ^/ l+ I7 o) D% R8 c
;; and initialize the traffic lights to one setting$ O0 M/ M( Q1 X% T$ I' V
to setup-patches. t7 y7 H2 G0 Y7 ^+ J, L& T
  ;; initialize the patch-owned variables and color the patches to a base-color
0 ]& D6 X% m, b  l5 `! c/ S: c+ G  ask patches
" g$ p9 E, i; l7 m; r  [
8 e! j2 B" s! K    set intersection? false
# ~/ `$ H8 p1 Y0 \0 `* Q    set auto? false
$ T5 q2 i6 Z# D5 V" ~! q4 o9 e8 Z' F    set green-light-up? true
: @9 D, b) x7 v' K    set my-row -16 W$ ^, q3 \; E6 N5 D- x
    set my-column -1
; L% k' d0 r' \8 q    set my-phase -1
% U  {( i! Q- q/ v    set pcolor brown + 3$ A0 G7 e6 r- E( Y
  ]0 h' `4 c5 e& z. B
6 @" k9 {6 }5 `$ S, p, E
  ;; initialize the global variables that hold patch agentsets) k* w$ J! [% d
  set roads patches with% \: C% F+ O# S+ K# F  g8 z
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ C! |# x: D; q2 C9 {. c" k' Z    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. J& U7 X. C* O0 z# _
  set intersections roads with, J; p; q% z! J- E! T" D' W
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and9 D& s; n6 q0 Y% [( Q
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 w1 b& _( ]) m3 V* a9 J( {3 W# ^0 ]! U0 t
  ask roads [ set pcolor white ]
& b/ y* V* h$ i% K    setup-intersections) Z+ Y) y& D: o& ~
end
% Q/ l$ k7 B/ [/ e  N( {其中定义道路的句子,如下所示,是什么意思啊?
* c5 I0 R/ b; m& I# N( B set roads patches with5 [  y! f2 S8 T" E! r
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% t" `$ F& P  F% U* _9 Q    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 Z# a! i3 N5 g
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, 2026-5-26 08:23 , Processed in 0.023518 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