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: 7953|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。
; O1 I* D4 L2 I4 ]3 Hnetlogo自带的social science--traffic grid这一例子当中,
6 D% U: ~- S' f% [0 u2 Pglobals
5 Y% e; w: W; R8 i6 V[1 O: \/ N3 f  M( l* w
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
" q$ C' q3 _% ?* c+ R- Y+ [( k- S  ^0 Q  grid-y-inc               ;; the amount of patches in between two roads in the y direction" A  `6 h, t' W8 t8 k, |# b
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
% ~; }, S/ K5 M0 ]+ q: \                           ;; it is to accelerate or decelerate
4 a- N9 I5 F0 D  phase                    ;; keeps track of the phase
& e, o" f  K# K+ s  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure; _& d* {# g& r/ I5 D/ C9 a6 ]
  current-light            ;; the currently selected light
) ~* z( P" n+ _$ m
. a- p2 \- [+ i2 x+ l' b) b6 J" ~  ;; patch agentsets
) b7 V+ D8 n( j# ]0 A  intersections ;; agentset containing the patches that are intersections4 E) X" `( D9 s# M# O0 q' W
  roads         ;; agentset containing the patches that are roads- \) F: L! ^  s: {9 w; X. t. s
]
+ F0 j2 i) q/ c0 L* P" V9 Y5 e8 N* Z( Z- [& X
turtles-own2 ~- g, J6 A) C7 z- M
[0 ^$ O! U4 D1 p  E2 Y
  speed     ;; the speed of the turtle
5 r! O3 M% z# K: l* M! w3 `$ R6 \  up-car?   ;; true if the turtle moves downwards and false if it moves to the right+ D+ _! n  A3 O6 I( i* O
  wait-time ;; the amount of time since the last time a turtle has moved$ y. C5 d( H0 m& Z
]
! N5 L3 m" M# V6 y9 j/ b- ?
; f1 W) H6 z( ]% K  L8 H7 {patches-own
) _: H+ _- ^/ F/ ~) u2 r" E[
. U% ~! w" K7 T% W& a0 e2 s- W  intersection?   ;; true if the patch is at the intersection of two roads
. C; u  z& H/ y5 h, ]  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.: s* ~: v  m' I7 G- e
                  ;; false for a non-intersection patches.8 O  i& |" b( [. S. X4 g" J+ c* p1 r1 b
  my-row          ;; the row of the intersection counting from the upper left corner of the6 H; K4 A5 S/ f7 f, O: b5 c
                  ;; world.  -1 for non-intersection patches.' w- M( M; U$ z
  my-column       ;; the column of the intersection counting from the upper left corner of the. |7 a6 s  h6 ?
                  ;; world.  -1 for non-intersection patches.& m" P, r8 ?7 y9 x$ F# U$ g1 ?
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.. n$ x+ W% V9 }+ ~% ^, m
  auto?           ;; whether or not this intersection will switch automatically.
2 h% k4 a6 ]" G6 a$ R" F                  ;; false for non-intersection patches.% I1 B! t6 @" o1 M
]5 _2 D+ y0 z- b' z- s: ?1 o' d

! W0 o- ~% e& S1 r
% B( o! `' x. @' {;;;;;;;;;;;;;;;;;;;;;;
) g" C% @; s' u/ Q5 |0 |;; Setup Procedures ;;
; ]$ u' z0 s$ {8 r;;;;;;;;;;;;;;;;;;;;;;& ?/ k% m- G9 @& d' P
- v, n1 k: X8 L' w: `% l
;; Initialize the display by giving the global and patch variables initial values.
' q! i, }$ K1 X5 r. j2 }  h5 [;; Create num-cars of turtles if there are enough road patches for one turtle to
4 ~, x# g( o% G0 J# O/ Y;; be created per road patch. Set up the plots.
( E* D  @. y. r; [to setup8 L- X1 {" g2 H/ E
  ca
. r- L& T( \% r, G- S  setup-globals
. ^5 s! l, S1 s
! Z8 b1 P( ]6 ^& K  ;; First we ask the patches to draw themselves and set up a few variables
8 f* v/ N) w2 ~7 l$ \( O/ u& c  setup-patches( n! e3 }7 _/ ~3 v! }: p. z# o8 p
  make-current one-of intersections" [0 H( j3 i7 U5 _  \
  label-current. [% c0 e2 U1 R, {# ]
% L5 U9 x/ {" h) Y1 g& e
  set-default-shape turtles "car"
- W9 {" c, c6 I) m1 a7 n* F: M! p' Z) z" D  s- G% F
  if (num-cars > count roads)
1 b& K: J9 ^; l8 x# I: k7 X- x! t  [
; c1 i. G! n* S0 U6 f2 ?% z    user-message (word "There are too many cars for the amount of "7 B2 b3 M5 n8 I3 C* U6 n7 C# ^
                       "road.  Either increase the amount of roads "6 g8 t  u7 G" B
                       "by increasing the GRID-SIZE-X or "
/ Y1 v8 g  z" C# u- H7 ^/ W9 s6 j                       "GRID-SIZE-Y sliders, or decrease the "8 V' f/ M3 \9 c% f& o
                       "number of cars by lowering the NUMBER slider.\n". ~, k/ |0 x1 j
                       "The setup has stopped.")
" \) j3 R$ L+ }) z. P  i    stop
. T0 D- S( H) y! b: y! o  ]4 I* z! S& {! D) M! }
! x6 i1 f" c( e/ o8 z( T& w
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color' I3 n, E  G4 v* p) S/ y+ l* o
  crt num-cars+ \; D7 }5 @( H$ l! q* ^
  [
3 ~& I- n1 h4 L# _6 U0 h* T; ?    setup-cars1 r$ J5 ?8 j3 @# e* \
    set-car-color
: p/ n; `2 p" B# I: Z    record-data
) Y! G2 V6 V8 _* `8 P/ ]2 `' F  ]
$ n& g6 T4 m) P' r6 I% u5 z
; W' U9 ?$ Y+ o4 ~0 u$ z  ;; give the turtles an initial speed
! {) p  m* i- ^# l  ask turtles [ set-car-speed ]  S1 s5 ~  d1 _$ F2 C; L

7 T5 n* M! a* w+ \7 q- A  reset-ticks% @7 Z' o9 q3 ~
end
/ X  t% T5 V. {6 S( b9 ^
; Z% U- u2 `  Z5 h1 ~! d# e;; Initialize the global variables to appropriate values
  g4 }5 J& _/ J9 e9 uto setup-globals; \5 Z$ {  g6 H+ R2 o6 n$ [' R
  set current-light nobody ;; just for now, since there are no lights yet' q5 ^+ M' _' m# G% V: d
  set phase 0
% h1 n  f" n) T4 ]- z9 s2 e& m  set num-cars-stopped 02 h; I. b& I/ T) B& B* P! N  q
  set grid-x-inc world-width / grid-size-x! a. T2 \* g& i" M/ J. g
  set grid-y-inc world-height / grid-size-y
& u; V, D3 Y3 n; V# t* t9 X# G0 W( l& @# S; {% j9 f3 e* L
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary* N) e4 i3 c) e. |
  set acceleration 0.0992 |) l' R& W: u
end9 A6 b. e# p( R- }; O

% b$ k% t6 ^3 N% T7 ]4 X$ b;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
# A6 u" {' K! W. }9 e* G  T- n' q, r;; and initialize the traffic lights to one setting1 [+ X0 G: j) ~# F# U; G) i6 ?
to setup-patches
/ J% B' a: E4 u% m  ;; initialize the patch-owned variables and color the patches to a base-color1 v' L& `8 \* H5 c
  ask patches
& s8 y+ E4 f" b3 ^. x/ P: f  [, h+ ~$ k% |! q* h; A6 F- F7 G
    set intersection? false
" D' {. x; C$ {3 k$ ?8 v( m    set auto? false1 h9 \, N( w6 y+ S; Y! g
    set green-light-up? true. [. i) @. C+ y' S8 q4 O
    set my-row -1
. F- d3 j$ }0 b3 o8 z+ @    set my-column -1
0 T( u+ f9 R1 a    set my-phase -1; y. {2 g8 y: Z4 O
    set pcolor brown + 3
: x5 `& b7 m8 M  q4 H  ]
- ^9 _9 p# P+ \3 I' V3 ?* L- D' o, R+ D% H7 r
  ;; initialize the global variables that hold patch agentsets! c5 W; C# T9 H8 L8 t7 `' G
  set roads patches with. b% F/ Z3 E% @+ C
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% p4 y' Y5 C+ _  j    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* p) n# ^& K* k+ w) y2 W' Y4 S
  set intersections roads with9 Y7 `( B( Q( U  A. q$ N$ g6 Y) I8 E
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
1 l& L3 O. [" d5 n    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( _; j+ G5 D) j* m4 Z9 S

7 Z! G. z4 y- N- J/ I! W. E+ Y  ask roads [ set pcolor white ]7 g1 ~/ S* i! d3 n/ ~
    setup-intersections. a6 j' R: `9 h; r3 s+ L
end0 ], M; A. O* R& W5 z5 C9 j
其中定义道路的句子,如下所示,是什么意思啊?
( X$ ]$ j$ P2 }  K, u% d set roads patches with2 W2 i: _) ]+ L2 t2 X/ I! ?
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ X1 A$ I1 f5 p# s1 Z1 t    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! c- w1 p) t8 ?) u3 Q8 t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, 2026-1-24 16:30 , Processed in 0.013750 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