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: 8734|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。# ]' `6 I) k: C: a  m; k, F; M
netlogo自带的social science--traffic grid这一例子当中,2 P/ A/ f$ B( k' M( a/ e
globals
) z) H: b7 n# }, C; N, |[! C/ [' L+ I) M9 f) [9 w
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
! W0 @3 c, _$ f: {$ ^( C3 L  grid-y-inc               ;; the amount of patches in between two roads in the y direction
6 T9 N  V6 e' f. E; ]" g( `6 Z  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
; u' {  |9 E5 B& A. k0 Y                           ;; it is to accelerate or decelerate
/ A- ]3 P6 O: I6 V  phase                    ;; keeps track of the phase
# D2 x4 X. `; {3 q# v7 }/ C  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure0 T# d/ Z1 h8 s% g- I1 z
  current-light            ;; the currently selected light& [& Y' K7 a$ X  }

9 s! [6 q6 k% q! M  ;; patch agentsets
2 h( G5 @& e% W7 R) k  E3 t: L  intersections ;; agentset containing the patches that are intersections$ W! a. |6 \( \) e/ Y5 s2 O- S
  roads         ;; agentset containing the patches that are roads; s: K- V" i! |6 w6 ^! n6 c
]( @1 J$ N& W- {2 N
8 i  F$ P0 ^3 d- ?# J3 X: @
turtles-own0 `+ s2 t2 {/ H4 Z& M% E4 _3 m. _
[
* T7 M8 P+ s6 w3 f' w0 r  speed     ;; the speed of the turtle
# U6 N3 k; p1 ^: S; r  up-car?   ;; true if the turtle moves downwards and false if it moves to the right) ?3 r1 D* W& C0 G7 L* u/ @# C8 j
  wait-time ;; the amount of time since the last time a turtle has moved
+ m/ l) v5 \1 a' Z1 t]/ d6 u: [5 V- T9 t6 C! G
4 [# j. V: w8 a- P
patches-own
. n5 O& ^  O7 r2 X; S' U: d[( ?( \) W% g2 x$ S0 F+ ^. y$ C6 a0 e' ^
  intersection?   ;; true if the patch is at the intersection of two roads
/ A, @& f. ~9 a9 [* x) Q& q& ]  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
3 h! V9 q" N( z% `                  ;; false for a non-intersection patches.1 \% ?, a3 _$ ^" W9 T* z) h  [
  my-row          ;; the row of the intersection counting from the upper left corner of the( `8 O* e4 H2 T7 k! c6 g
                  ;; world.  -1 for non-intersection patches.. K! ^- s0 N( e- u
  my-column       ;; the column of the intersection counting from the upper left corner of the
* s7 X2 s% k( u1 z$ q% D2 s                  ;; world.  -1 for non-intersection patches.6 p- e5 u  Y; e' h9 z: a: e9 k
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.& ^& E, G% S( M" s6 Z7 t
  auto?           ;; whether or not this intersection will switch automatically.% Q) Z) f' J7 i
                  ;; false for non-intersection patches.0 |! C# Y3 k. u8 E
]  Y$ k, \1 }) W. f; e5 I

7 ^. F( ~; O6 x: V# K1 a; x. X: V" |- f
;;;;;;;;;;;;;;;;;;;;;;- T3 _; k! i( y, @- G
;; Setup Procedures ;;- C8 _9 U/ R+ V. s5 r
;;;;;;;;;;;;;;;;;;;;;;# j' t0 ]8 w, K' p

, t: K6 o; P& S4 m' J;; Initialize the display by giving the global and patch variables initial values.$ W3 O6 |$ M* h. ^* j$ l
;; Create num-cars of turtles if there are enough road patches for one turtle to
6 a9 o9 M2 _& p- i7 ], c1 B1 x7 q1 K' Y;; be created per road patch. Set up the plots.4 V+ x0 `2 s& N) m" r% e8 _2 U
to setup5 R' F# K, U) \: A5 K
  ca
4 d4 V, D! J- e& ^+ S# `  setup-globals& k, L4 c! @2 w9 G$ n
' t- R( L- z7 G' s1 l( i* e
  ;; First we ask the patches to draw themselves and set up a few variables$ v/ l/ a. d8 t
  setup-patches- K' A9 S( K! \, N& t
  make-current one-of intersections& w$ f9 j& x/ }' W0 N
  label-current
3 c0 ~) Z" H, G1 X  J  a7 M( D" L
  set-default-shape turtles "car"8 n) u$ e7 q# Q" L, h; W
( s* I! P- ^* X8 r! ^  @7 j( p
  if (num-cars > count roads)
, U9 w# k! r. l6 [  [% p9 Q; q" B, u( e" j5 Y
    user-message (word "There are too many cars for the amount of "
' A2 C2 S3 ~' {8 ]7 T. r# N                       "road.  Either increase the amount of roads "
& Z2 G8 E, c3 M                       "by increasing the GRID-SIZE-X or "+ x* }; \! ?$ V" C4 {  \& c6 S
                       "GRID-SIZE-Y sliders, or decrease the "
. j4 V; v: c# u( |                       "number of cars by lowering the NUMBER slider.\n"3 K3 u# J: b& F& Y2 J. ~9 w# n
                       "The setup has stopped.")
% Z% i( o5 S3 O2 L3 M7 o    stop
# _% E5 d4 Q& Q: s& |; c3 m  ]7 o% G* G% l* Z, V$ i- z* o
8 m4 i: L/ n  F; |, g* T
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
; |! m) v3 v0 X. w  crt num-cars
1 F2 y$ n9 t1 B! {* q" \  [
9 N( m( P1 p+ d7 N7 B    setup-cars
$ D/ s! u% i/ Z; T9 t; `    set-car-color
. h% m/ G/ Y( k/ I6 y- o    record-data5 L, b2 P  q: U
  ], W$ l, h/ ^6 B( ^0 i

4 w) Y- R; A* I$ }3 |+ {( V+ \  ;; give the turtles an initial speed5 D0 S% d+ _& [- ]$ d" _, W7 q
  ask turtles [ set-car-speed ]
& R# l* u  J$ m# M% g6 {8 e, N7 j! d) z5 B
  reset-ticks
5 T$ \3 q& L( x( tend
9 b/ Y8 O) L' o- q+ }4 d% `  w
3 v8 |- i6 f9 z& G$ [# R;; Initialize the global variables to appropriate values
! X8 r2 S& r* X) M4 Vto setup-globals3 s, g% n- h2 ?3 ]* t
  set current-light nobody ;; just for now, since there are no lights yet) i' u9 E" p/ l' M( c9 x& B
  set phase 06 s& o9 ], W" ^. w3 P1 [
  set num-cars-stopped 08 T! [. v! c: c
  set grid-x-inc world-width / grid-size-x
4 D  ^: R( K5 U5 H& U" G  set grid-y-inc world-height / grid-size-y6 _/ |! F7 e! c, L8 ?% z, Q. C

8 y+ d! x7 t$ d9 }- j% u. f2 p" P  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
, {3 K0 n) j9 R. E6 h- J, O  set acceleration 0.099
9 `- @* C( N+ j" V/ kend
, t: r# o8 ]( I4 ~& ^3 l7 d' V0 U6 Z( U9 r
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
" |6 s! h! D( h9 ~2 O2 z0 \" T;; and initialize the traffic lights to one setting, S, b2 I( @: x, l- c' Q, ^# ?) a
to setup-patches
: ~4 F6 ^2 i7 h! k$ `* g  Y" u4 {9 L  ;; initialize the patch-owned variables and color the patches to a base-color! f5 O. E) I6 p( ~
  ask patches5 W: S3 G/ r! u) l3 V0 v
  [# x! U4 a, n- t3 d" A" n4 p
    set intersection? false
; S6 S/ b- Q7 b8 j3 I5 l4 n* m; s    set auto? false1 Z2 b, q% f% ~
    set green-light-up? true! t8 e# b, P/ q
    set my-row -19 G. O* \& Q# m
    set my-column -1* H+ R5 ]. N. r% P6 d
    set my-phase -1  Q- d% W6 V0 O" v5 S7 ?( ]+ o
    set pcolor brown + 3& k, O# g9 w* y# N! V/ [2 P
  ]7 V# q' G6 T& k: p3 l
& S) b5 f$ w, Q$ m( X
  ;; initialize the global variables that hold patch agentsets
% m3 Y# R, l: i$ ?$ D1 x( v  set roads patches with
7 ]; J+ R- w& L8 X/ c    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 I, a! H4 ?+ o" m+ a. w
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- t: n3 K. W9 B, {. M2 K3 j5 d  set intersections roads with8 I3 c$ E1 G- w
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
/ v/ q: `0 t0 B7 h! r3 I    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 l3 ^( R6 g6 ?6 X- q/ A% q4 o/ `8 Q: q9 b1 S2 R
  ask roads [ set pcolor white ]
/ _8 ~$ D/ b# Y: M2 x    setup-intersections0 Q4 ]+ {; v" C
end
9 n8 R3 J! Q, A; z( s其中定义道路的句子,如下所示,是什么意思啊?, o3 ?( Q1 U# _
set roads patches with
, ^/ u. F9 r5 f1 v    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& N8 W1 N: k) j' ]6 ]
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 Y% k3 f# W7 k7 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, 2026-3-7 05:36 , Processed in 0.020205 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