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: 11518|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。( P) ^0 Z; @1 C) f; c
netlogo自带的social science--traffic grid这一例子当中,6 b2 i2 z' @# f7 ^
globals. [5 ]7 q$ T9 Z8 Z) U' C+ N
[
7 e% H- B# `! @7 ^- X  grid-x-inc               ;; the amount of patches in between two roads in the x direction
5 ^4 v1 i7 [# s% l  grid-y-inc               ;; the amount of patches in between two roads in the y direction
& y2 c6 o9 a  Z( t' ]  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
2 ~( s$ g. A: L4 Q2 V% P0 ^                           ;; it is to accelerate or decelerate
0 \5 W& G" x; N4 R. _' `  phase                    ;; keeps track of the phase
7 U, P! n* J5 ^/ @( V  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
7 {1 B( {; i9 V3 n  current-light            ;; the currently selected light
; Y6 ?4 R; s& ^: J1 U* o: [- Y" s1 ^$ l) c8 m
  ;; patch agentsets, k/ _3 f$ C5 L& |9 o
  intersections ;; agentset containing the patches that are intersections. \; c9 o, w4 h& {
  roads         ;; agentset containing the patches that are roads
; Y% j" f7 ?) |8 k: n]# h* E4 U+ Y& Y8 C+ _2 n

3 `+ J1 O( H0 X+ ^turtles-own
7 v" u2 ?7 {+ v( ]8 v[
4 H, ~7 l: g+ h7 k  speed     ;; the speed of the turtle
- P7 Z: ^0 V  T0 y: |' Z  up-car?   ;; true if the turtle moves downwards and false if it moves to the right+ f) x* r5 p- u* ~) u2 D: t
  wait-time ;; the amount of time since the last time a turtle has moved/ o7 }6 E3 N' W* E, R; V4 M
]
, i# U$ B4 _7 ?
; {7 c6 u0 S6 ~" U  b& dpatches-own: d$ b: Q/ }  ]4 i: n
[$ S' T" D( u/ @
  intersection?   ;; true if the patch is at the intersection of two roads
& @1 {+ R0 W; R. Z8 M5 }6 H$ {  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.2 h, D) i4 _) X% G& k) T
                  ;; false for a non-intersection patches.( u6 _3 W7 h% P
  my-row          ;; the row of the intersection counting from the upper left corner of the/ y; t" J2 h" G! m3 Y8 }3 d. s9 Q
                  ;; world.  -1 for non-intersection patches.. f$ a1 R5 c0 S: }$ M/ n  u) `
  my-column       ;; the column of the intersection counting from the upper left corner of the
/ m& Q) g  H' o8 P                  ;; world.  -1 for non-intersection patches.
( R' _" [2 j! x; m6 v" s  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
  u  X6 X4 Y' U9 d/ m4 w% L( z  auto?           ;; whether or not this intersection will switch automatically.4 B, ?$ P! u! h
                  ;; false for non-intersection patches.! T6 O: y7 X, |. j4 f
]4 l0 `% z" H& a, [

8 J9 }. o9 X3 }* T  K) A) k; s( K8 w, _! S& o  l' ]! c
;;;;;;;;;;;;;;;;;;;;;;6 P1 o1 @. Y6 Z
;; Setup Procedures ;;& M# c( I1 k; R- C! m
;;;;;;;;;;;;;;;;;;;;;;% V( F$ J' b8 x9 H( l, u" ?
4 c  c) k! ]5 A% ]0 B# }
;; Initialize the display by giving the global and patch variables initial values.
8 Y/ y* T# Z5 f5 S;; Create num-cars of turtles if there are enough road patches for one turtle to- c+ S( P9 S6 w/ ]/ B' c. N& j
;; be created per road patch. Set up the plots.  W; {4 j" B  d5 e+ @! }* Z( _
to setup
0 a1 G4 ^: p0 }  q  ca
8 g' D, o3 n0 E& ?. ~  c  setup-globals  Q4 M9 O- [$ z: R8 W# {" l
8 G2 y0 C, b, n0 `0 ?
  ;; First we ask the patches to draw themselves and set up a few variables2 ^( d! q% r3 Q* [9 J
  setup-patches8 @9 Q7 Q4 E' K  f
  make-current one-of intersections
6 @0 t& k7 M& H6 \1 Z! M  label-current
9 n- T2 X0 }$ c+ b1 W7 o9 i0 c) v" f/ k9 n  W( L, O$ _
  set-default-shape turtles "car"
7 K* [% f# B- e2 N
$ r1 I9 r, o# u9 q$ `- `, G. l  if (num-cars > count roads)
3 Q9 f) x. {( `( e7 u! S6 R( g  [. J' U) n- q2 a
    user-message (word "There are too many cars for the amount of "+ ^" W! J- q1 G, v8 ]  J5 a/ ]
                       "road.  Either increase the amount of roads "
/ [& ^( N; s" {' W% h% @) E                       "by increasing the GRID-SIZE-X or "4 ~- Y" L, Q3 k3 V
                       "GRID-SIZE-Y sliders, or decrease the "! |) Z  F- b9 {
                       "number of cars by lowering the NUMBER slider.\n"
6 C  K. Z4 f" {: S) m                       "The setup has stopped.")
) P, O0 A* B# `, B7 |5 F    stop# S8 Y6 ~+ l$ V1 U' ^
  ]
( V" e  r: w1 O% W# T3 Z6 D2 U" l' P1 t4 w6 r6 i* p- f
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, }2 L. m/ v/ v# E& n/ f
  crt num-cars
! C4 b* c5 `; x+ x  [6 d2 [& r& G" c
    setup-cars
2 ?# V9 F/ v: \' N6 @. I2 M) K    set-car-color9 A1 f6 P: \  P6 N2 s! r
    record-data
9 C$ C5 B! I, j4 e" g  ]
2 e! v( s8 o# z. {+ v) t
) h: x) y: f4 Y  ;; give the turtles an initial speed+ }$ n# h' _7 n. l+ }
  ask turtles [ set-car-speed ]8 \/ R/ c/ }' a& T/ ]# B+ d8 J2 L/ J; w

/ w9 a- v; A$ |9 J2 m- W  reset-ticks. H! X$ b/ Q" N# p! I' d
end
6 B) q/ A) V4 l- V2 O8 ^/ p* U; N- Q3 _. M( K9 u
;; Initialize the global variables to appropriate values
3 I/ x  V5 B; w+ B4 u! ~to setup-globals, @9 P( |7 O1 H! H( i8 _5 a8 f+ s) k
  set current-light nobody ;; just for now, since there are no lights yet
, P; x# q2 K  q" |+ }% Y  set phase 0
  N; i: H, c( f0 p  set num-cars-stopped 05 V4 f$ B9 D) A7 J2 l+ u
  set grid-x-inc world-width / grid-size-x$ I2 E5 H' k& t9 a% [; s* E
  set grid-y-inc world-height / grid-size-y
/ c% j- Q- S* `2 N9 W3 b
% N# Z5 t4 D' d1 p+ L4 L  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary! I6 F( k2 j$ D/ p% G. s% D
  set acceleration 0.099; H- k( b, D0 f- W  q
end! u: W4 A3 f( p5 v' y4 R
+ W5 A5 ?+ }( |" Z2 y
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,! s: C0 S/ j. ~3 ]% }7 @5 s  t! J% n
;; and initialize the traffic lights to one setting  J1 u! }. R7 |5 s: C. B
to setup-patches  z- p3 @* _& ]' _/ O6 \
  ;; initialize the patch-owned variables and color the patches to a base-color
# Q, g2 X# C8 V  ask patches
2 {0 U# P: [" V7 x! D% \4 r: W! P( ?  [
! R$ I% s. k1 x/ t% y6 b2 e    set intersection? false
2 s: H0 j5 \& S) c; c    set auto? false
+ J, a# n6 p9 x. i6 |    set green-light-up? true
* u- N; d9 u& ^9 `: f3 B0 z    set my-row -19 h  a9 @" c/ _
    set my-column -1, r0 n% A6 u! L5 V( \4 |- g( C
    set my-phase -1: V3 a# L! v0 \0 Z3 K
    set pcolor brown + 3
) `2 K" Y- `6 w2 Y  A" \" S' ?0 b  ]
# w0 _2 ?- N7 W
: J% W' K; z, B: I9 _9 q  ;; initialize the global variables that hold patch agentsets
5 b  }& ^0 `# U  set roads patches with
3 I- T; M' C, {0 [5 Z9 s& F9 |, _    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, t4 ]( Y# _# v* E4 y0 t    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# \7 N; L* o8 \$ `  set intersections roads with
5 I4 m' m% k- |# E* U# k6 U    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and; d/ [! z- ~* y
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% E) o" \5 C; p$ \6 N8 j5 O3 D, M# R! ?) o- Z
  ask roads [ set pcolor white ]
2 \9 G5 j( i. Q* N' g% z, d4 _    setup-intersections
# l. c) C& v) m( s5 hend
1 }% ?2 ~8 T: i9 a; i) T0 N其中定义道路的句子,如下所示,是什么意思啊?! z) z, f4 d$ a; H  I
set roads patches with: I( }) H4 H+ P6 _" N. O
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 N  ^3 R$ ?$ Q6 `; N) X
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* P/ \- ~. @4 m8 m$ O/ R# {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, 2026-8-2 01:51 , Processed in 0.022521 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