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: 8109|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。
1 {7 v  J- l) tnetlogo自带的social science--traffic grid这一例子当中,- }2 N! k# z/ P' \* P7 v
globals! U1 d, N; E+ }+ a6 O! w
[1 g$ }! h# U2 W  L
  grid-x-inc               ;; the amount of patches in between two roads in the x direction1 n2 k) h( Y! s+ T/ |4 |* y
  grid-y-inc               ;; the amount of patches in between two roads in the y direction
# P' p0 y/ Z0 e  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
# [% u% g$ {. E" V, K6 I                           ;; it is to accelerate or decelerate
! N: L2 [6 c9 D$ Y4 Z  phase                    ;; keeps track of the phase
/ |0 F! c$ `9 P' }' E  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
6 m; k# W5 l$ N  current-light            ;; the currently selected light
* x8 W3 V* ]. u' U  `, G5 L1 c; A3 a8 w
  ;; patch agentsets9 `8 P# q! X  M7 }3 _& ^$ S& C
  intersections ;; agentset containing the patches that are intersections
& b: u& f, |& v1 N" f0 `  roads         ;; agentset containing the patches that are roads+ ?+ u3 C( S/ `: ~& o1 j* M
]
" O3 E% ]( P: r1 O) e% @9 I# @5 c7 @& A% q3 }1 s" i0 M
turtles-own
4 @& ^; ^. O1 V[
$ v: V/ `( ]' g- J  W  P1 P  speed     ;; the speed of the turtle& L+ j( K: ^/ Z  T; q
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
: g' k/ \& n2 l. n3 m  wait-time ;; the amount of time since the last time a turtle has moved1 i5 c4 t5 c; b/ S9 _% q. F+ Z8 ~
]
9 J2 K5 m' y  O% N& @% B# v9 C& i( x: l; S% J
patches-own  ]5 a7 v8 R4 y
[, F' G* J, r# ^: j" G; S  L6 Q
  intersection?   ;; true if the patch is at the intersection of two roads2 H$ G# ]+ ]9 [
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
' k/ [2 [4 C# m- [- U2 s/ j* n8 e                  ;; false for a non-intersection patches.+ g% v( Z, m$ A3 K* ]
  my-row          ;; the row of the intersection counting from the upper left corner of the; x4 t% R9 i8 D5 R8 ^8 `
                  ;; world.  -1 for non-intersection patches.
4 k  ?* g" [7 U. D: a- ~  my-column       ;; the column of the intersection counting from the upper left corner of the
  r# E# j! `7 u+ b6 |                  ;; world.  -1 for non-intersection patches.
' r6 a  d4 J$ B  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.( h3 Z7 W0 W7 b, g& i
  auto?           ;; whether or not this intersection will switch automatically.
$ {, }/ ~) m, N9 v! Z. f. I+ ?% G                  ;; false for non-intersection patches.% O9 C4 R9 K% ~6 u: E" N
]
" Z; z* R2 }: Z/ P7 v3 k' ]- y! l* w4 t5 U

, f0 W+ \6 C$ H* ]/ v7 y;;;;;;;;;;;;;;;;;;;;;;
, ]! ]& G1 \8 m2 V2 q;; Setup Procedures ;;  J) P& W3 c5 y, C
;;;;;;;;;;;;;;;;;;;;;;% n; t9 V8 u  d+ v, c& |2 O7 [

* u! P7 @. Q/ l7 R* G1 E4 d;; Initialize the display by giving the global and patch variables initial values.
- Q, a, I$ y$ \" g;; Create num-cars of turtles if there are enough road patches for one turtle to: W4 c# V. g* z' B) l
;; be created per road patch. Set up the plots.& K% Q& E* m' U
to setup6 \( ~) T; d& b8 M
  ca. L, D9 k; N  N4 ^! V* O& x
  setup-globals
, D  ~& |: u! H; @
& y8 J/ k$ S- Y4 n  ;; First we ask the patches to draw themselves and set up a few variables
+ d4 d; |0 L  f  setup-patches8 ?* I' N0 d) S/ {# b0 J: C
  make-current one-of intersections3 B1 v+ ?, t$ f3 ^- n  m# ^; R+ x
  label-current
6 J8 {$ }+ u# M6 R% e
# h/ P3 S5 Q1 P" ~  set-default-shape turtles "car"
& P+ d  q" Z% O4 B9 X7 p/ s1 k  S6 Y( M, J/ Z2 ]3 F
  if (num-cars > count roads)) @7 z! k1 v, a  t2 H, ]/ N& E/ q& r
  [; `' d" N* W$ V8 a8 j
    user-message (word "There are too many cars for the amount of "
1 T+ u: v8 x# ]) S/ B0 R, J                       "road.  Either increase the amount of roads "
* A. E" l0 [, A; F                       "by increasing the GRID-SIZE-X or "
% Q4 V; X) r  ~$ `  o. J                       "GRID-SIZE-Y sliders, or decrease the "
% e/ L( ?* P" i" i9 @                       "number of cars by lowering the NUMBER slider.\n". j" _% y5 \7 E! M  {+ t
                       "The setup has stopped.")) ^/ U1 O+ P( Z9 f9 ?* y/ C
    stop
5 p+ b* Y" j7 D" Z  ]1 l) [+ {7 r) m& c  \

% X8 X& }& f+ Z0 u( b  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
) h0 p  r' d5 S' Q0 A7 p  crt num-cars' {% o" e  W. H3 A( c. o% X0 u! f! ^) s
  [( k7 H5 m. Z. q! g$ Q6 E
    setup-cars
; N0 P9 a- H* j: Z+ o- i) S# \    set-car-color% L" k, I& Y  N! V! [' Z% e
    record-data* O* n$ c9 j: T, y9 G0 E
  ]
, F% ?6 J) n2 x7 g) Y+ _) H- e# ~7 i7 g
  ;; give the turtles an initial speed- t8 x$ x7 v& Q) i* V. z
  ask turtles [ set-car-speed ]
% b7 r( b3 f, G+ j* Q1 ~7 R7 Z& O: w- ~9 p
  reset-ticks
; Y( v) }3 z4 F7 dend
' H$ T) @% Q3 p  D6 T
, H8 K$ g* c6 _7 R& p* `/ y* B;; Initialize the global variables to appropriate values
" r# u& d, ?0 x) Z) hto setup-globals
$ Q) V" h; [0 f2 d& H1 }  set current-light nobody ;; just for now, since there are no lights yet
1 M5 ?7 ^! H# E7 f: b  set phase 0
" G9 c4 y- [6 I, c0 D7 l  set num-cars-stopped 0
9 E3 ]$ q0 ^* L% f) \  set grid-x-inc world-width / grid-size-x' y& g0 A7 u9 Y$ q
  set grid-y-inc world-height / grid-size-y" B3 A5 G$ D7 a  `1 D2 v  }

% V6 Q  U" j% V& p  y6 I+ z) w6 @- o  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary2 _5 w4 ]+ S4 u
  set acceleration 0.099; P. S" k  ~7 H; b! j- M- X5 |6 d( l
end
* ~; z5 Z' s  F/ l! Z" \* F) h  a: @+ a7 f! ^0 G' {. q5 M
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
! h- G. A" g. \+ a) y;; and initialize the traffic lights to one setting7 V+ d. u. l0 a! N
to setup-patches
0 x3 e3 p3 c4 X2 K- x  ;; initialize the patch-owned variables and color the patches to a base-color+ r" v. {5 E" q% W; U; ~
  ask patches& B2 m7 [. J+ N
  [/ t  t$ D; f% I( e6 @
    set intersection? false. t3 C3 }6 [0 u% ?" L* [% U$ W1 X
    set auto? false1 G4 S$ ?$ u! k; V" i& s* L
    set green-light-up? true& T% b7 _4 v5 _# O) N" j
    set my-row -15 e$ G5 O5 y5 L5 l# T% T' a
    set my-column -1# o# E1 x5 }; g1 |% C
    set my-phase -19 T6 \" L* p" c  T, Q/ t) m( Y
    set pcolor brown + 37 K! N- m/ f/ a5 C4 F) T
  ]
5 z& Y0 R$ @- d0 z9 h
4 R' I" h. K! h. l$ \) @  ;; initialize the global variables that hold patch agentsets6 C2 I# U  u4 Y  I5 t- H% j
  set roads patches with
5 a  d4 N( h+ q1 d. U  v6 k6 |    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 p6 G1 U$ ^& k- \6 H; }/ A
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 F) C: C( Z4 c$ e, r$ A1 K* x3 K  set intersections roads with$ \# M( {, ?+ \. [$ f4 Z
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and. w3 }" f* t: m
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
( [( A' v1 `; ~' N8 U0 F7 l3 \4 Y& p; F2 K' ~) K
  ask roads [ set pcolor white ]/ }" Q7 ]8 P8 z% f; h& Z
    setup-intersections
, @5 O* N5 m# B9 S% x: Lend
4 {% Z1 F( I- o! f& ?  R& k其中定义道路的句子,如下所示,是什么意思啊?) @/ M! i: f9 @# N  c
set roads patches with! h  q5 h& p% L3 M5 x8 \; J) p
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ w: [1 ?7 p& h8 q  h) U" c    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& v) G1 Y6 N3 E  v, q. O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, 2026-1-31 23:56 , Processed in 0.015642 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