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: 7660|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。
# M+ e; W* s. u* d# b& U3 Xnetlogo自带的social science--traffic grid这一例子当中,
7 N: b8 q0 J6 G% H% Jglobals
5 w# r0 z9 j( h. ^[( E" M5 y4 ^; Q, A1 R- T- X9 r
  grid-x-inc               ;; the amount of patches in between two roads in the x direction, d. j( A. y" ~; m# H
  grid-y-inc               ;; the amount of patches in between two roads in the y direction
) P( \, S7 L) S. T) W  acceleration             ;; the constant that controls how much a car speeds up or slows down by if6 h2 _8 X$ U, t
                           ;; it is to accelerate or decelerate3 L) }* X8 S+ v
  phase                    ;; keeps track of the phase+ @! t; }  P0 t3 I! b0 f
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure& d# v+ Z+ L4 O+ a; @3 M- i- P
  current-light            ;; the currently selected light, M9 E) c1 J! c$ ?+ q
7 k2 Q4 m) j1 J7 [% r$ n* G. r5 T
  ;; patch agentsets- P6 ]  E! Z+ h( Y0 J& N, \3 X
  intersections ;; agentset containing the patches that are intersections
. U! u+ r+ u  P% _  roads         ;; agentset containing the patches that are roads
' {5 b6 ?$ N: [% |]; N7 k9 L- s' t2 y$ A
; a* ?: {$ t; ?- k% }$ L
turtles-own
# p9 p# A/ C8 |( }# O[
2 e* T: u) _' I( A" l  speed     ;; the speed of the turtle) @3 F4 `. y% h( o$ k) w
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
& A9 ~9 C( j/ [/ V( J/ u5 Y  wait-time ;; the amount of time since the last time a turtle has moved. f2 N  X3 t7 W- W  n2 |# J
]* d4 ?; a" v/ [/ r0 s0 P) s; ^

  h& F! }. {9 L# B9 h$ G5 Y4 Mpatches-own
2 P" \5 z. @8 m4 P: j[
7 U8 A) Y# L9 p2 X) f! g/ i  intersection?   ;; true if the patch is at the intersection of two roads* \1 L6 @! d8 d" Z
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
! n9 ]" Z. n4 @) G) @0 f                  ;; false for a non-intersection patches., u# N8 K; f0 H! h8 K+ n
  my-row          ;; the row of the intersection counting from the upper left corner of the
1 h& s$ o/ a' \; C% \                  ;; world.  -1 for non-intersection patches.6 `+ J# W( ]+ x3 S6 p# C% s  K
  my-column       ;; the column of the intersection counting from the upper left corner of the# r5 ?) I# J8 {4 V
                  ;; world.  -1 for non-intersection patches.3 Q" s5 T1 @8 E( J
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.) W& Z# `; A& `* ^; m' E
  auto?           ;; whether or not this intersection will switch automatically.; z$ a, V& k% D' V! ~
                  ;; false for non-intersection patches.
" G8 ]3 l  q+ o" B' Q]3 m' O! U9 T, J. z3 D3 s+ N: b

3 e' K2 ?0 a/ K" M7 J$ }7 ?& U7 Q; A; B5 [* H. ^
;;;;;;;;;;;;;;;;;;;;;;
! ?+ L1 F2 S* m  Y% ~, v;; Setup Procedures ;;4 t9 g( M* f; G4 ]2 M
;;;;;;;;;;;;;;;;;;;;;;4 e8 S8 s1 {" D- D1 Q

8 d' D  S# h( O# D0 J  S  \;; Initialize the display by giving the global and patch variables initial values.
6 Q0 q7 M& v2 I; J4 I) `* F;; Create num-cars of turtles if there are enough road patches for one turtle to& j1 X0 @% L3 i" N5 I) c8 v' `
;; be created per road patch. Set up the plots.
9 [% {" x' h5 |to setup
5 e) A$ z* Z/ t/ d6 S, _9 a# m  ca
5 _. Z1 `1 [& K; G( \( T  setup-globals8 j& ], P! ~! k( g$ g$ K8 e
) ~$ t  C- v3 t2 t1 h: y
  ;; First we ask the patches to draw themselves and set up a few variables% F! n  D' V5 F3 _) S! l# i3 r& Q
  setup-patches6 X# v3 v' @5 j; x  ]
  make-current one-of intersections
" A. g. q9 A) u  A& |  label-current/ w5 q; N+ I) p2 L

8 M, Y) V# {4 k" A) |  set-default-shape turtles "car"
, {3 H$ F3 q& ]' J8 A) R; }
. o0 k  @2 w$ R" J* b( F' i! z# e$ u$ a  if (num-cars > count roads)' b: y/ S) E' h) e
  [
' i0 h+ Y' \1 G, Z% O    user-message (word "There are too many cars for the amount of "
/ {( W8 t% h% Q* P- B                       "road.  Either increase the amount of roads "
1 D* u2 t) q5 z& N9 j( |. l3 g                       "by increasing the GRID-SIZE-X or "
0 e4 Y' C. I7 e0 T/ A                       "GRID-SIZE-Y sliders, or decrease the "
& T3 D0 `6 M) Z9 K/ I( z2 a, U                       "number of cars by lowering the NUMBER slider.\n"0 x) x1 y# j) U6 p3 X8 c
                       "The setup has stopped.")
& [, C% `3 h+ y3 J' t* z    stop
9 b9 A$ N/ F4 U3 }$ ?  ]
2 o3 V6 x+ P) S' k, N
0 F( q; n: Z$ z  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
9 o3 M& n+ r6 k/ m% o& J  crt num-cars( {3 j2 e( H9 k- G2 i2 T5 C
  [% z" O" D" B. C3 X  Z8 A! r! X
    setup-cars7 g' ]1 P( c' F. d
    set-car-color+ ~6 Q; l" s4 ^' s" l) F  v9 S: u9 F. b
    record-data
/ A$ v' L( ?" N9 M( T  ]4 k/ k/ j, m! \3 ~
2 _' I6 x: c6 F$ q: v$ c
  ;; give the turtles an initial speed
" p) O5 y4 G) P" q( ~5 V  ask turtles [ set-car-speed ]5 X1 _: W+ \5 V0 S! Z

( C' S0 \! _, P- J  reset-ticks
3 k/ Y5 d$ r5 c# N' yend$ B; P; ^5 _+ D4 o$ |

7 T$ Z% k2 O! X3 L;; Initialize the global variables to appropriate values2 R+ {9 O# a3 f: B, P% q2 V
to setup-globals% Z# P6 B* H6 [- X& l
  set current-light nobody ;; just for now, since there are no lights yet5 V# e8 H' U: l% @* q, J3 u
  set phase 08 {: W$ f4 i( n- v0 w5 q& ?
  set num-cars-stopped 0
( p- |+ `# k* `  set grid-x-inc world-width / grid-size-x" R, S" M3 h2 ^5 h7 f# p$ i
  set grid-y-inc world-height / grid-size-y
/ N4 y  I4 t6 G7 {8 m4 f$ D1 u* L) _
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary( Z$ J7 B9 L! ~5 m3 R% X2 p; {8 w& G
  set acceleration 0.0991 ^. F  A6 l- [, _9 P* x
end, _- l$ K2 O% K5 F/ L9 d& S, r

2 a5 ], Y7 f9 q: P/ k: e+ ~;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
* j5 v2 D8 @6 P/ c8 O;; and initialize the traffic lights to one setting' k! T9 q/ j+ b  S
to setup-patches3 H# _+ F* X7 e
  ;; initialize the patch-owned variables and color the patches to a base-color
- s4 E* |) I4 J+ h0 ~6 v/ K  ask patches8 |# s0 n  ]! [8 x4 F5 G# a
  [3 R! I) r. K! f- @) o5 t
    set intersection? false  z% A- \) T) m- e
    set auto? false
4 u: w/ M( n% Q. m( \    set green-light-up? true
$ P' l9 Z: F$ t' F" b" q9 q& e8 l    set my-row -1( f; C* h1 u. h
    set my-column -13 n8 i3 N# L8 C5 j. g  `) }! ~" B
    set my-phase -1' A1 K1 A# F% M' I
    set pcolor brown + 3/ {0 x6 U4 x$ O$ k
  ]
  d) d6 x" J( b5 m: r* @: m, ^7 }$ B- K2 x
  ;; initialize the global variables that hold patch agentsets
: }( F5 |  }6 v2 F  set roads patches with6 f6 }/ c# `. M" a# N* q
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or9 o3 x! S. v* P- w
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ n3 W  U) ^7 B+ M* ?5 C
  set intersections roads with
# V8 H. Z  O6 Z& |7 R3 W( a& S& V5 d& b# a. Z    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and0 B6 u) h/ p! v1 v  s; V/ L4 @
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- v' R) C- [6 g7 p& h

; |- K8 ~" B( [- N+ T  Z  ask roads [ set pcolor white ], N* y; F% e6 s8 s$ b
    setup-intersections$ ~$ [* \0 H+ A$ {0 _0 ^& y  s' D! h
end! }. w) [6 d$ B9 C3 N: ^0 x
其中定义道路的句子,如下所示,是什么意思啊?1 T/ V/ D9 l' a* _3 f) e; P
set roads patches with
2 s5 q  s* ~6 S, X8 a8 E/ ^    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' V- P9 c! E' p4 ^; r* x3 P
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 Y' o1 m5 q: U7 p) s# L8 Z1 z
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, 2026-1-3 00:56 , Processed in 0.016213 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