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: 11249|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。
$ L2 e/ e4 z% d0 tnetlogo自带的social science--traffic grid这一例子当中,
3 \# W2 |# X- Oglobals
5 O: P6 A' K" v2 e. _6 W[
( d/ y9 v' \; E, W, h$ C! D8 W6 e  grid-x-inc               ;; the amount of patches in between two roads in the x direction
; ^9 C7 A2 x) ?8 L# I0 h! D  grid-y-inc               ;; the amount of patches in between two roads in the y direction& B7 |4 L; }) f- ?7 {( F
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if! s, C5 C5 \2 \. }" m
                           ;; it is to accelerate or decelerate
  ?3 L3 o/ C0 {  phase                    ;; keeps track of the phase
8 w' f" A! g: v& C. C2 Y; }# t* `  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure2 t* j$ V: Z$ u: Y2 Q2 M; U. I0 o5 b  e
  current-light            ;; the currently selected light
$ J3 ^7 _- I3 U5 D  J2 j1 p0 f4 ]( C* [& e. S1 g
  ;; patch agentsets
$ g0 i4 Q; p$ {) j" U5 P3 b  intersections ;; agentset containing the patches that are intersections* L7 D, \* r/ g4 r& T1 l) H0 b
  roads         ;; agentset containing the patches that are roads- E5 i7 b6 z. Y; Y
]; ?7 J- v- G5 }1 K  M3 j
* ~* ?. w6 ?" j+ T
turtles-own
3 m( r+ F* p7 s6 n[
, N0 o% u* y) l2 y! H  speed     ;; the speed of the turtle3 L2 f/ |& v: q
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
' O" V1 Y* Z% g  wait-time ;; the amount of time since the last time a turtle has moved1 R5 z6 `( P! K! l+ r& Z) I. x
]
/ Q3 U6 g, @. L- X1 U8 E0 Q1 J1 H$ @, [7 i: R# x9 _
patches-own' H, y% H3 c! ?% B' _8 q
[: T0 R0 \& G# T# V) \6 a/ G. W
  intersection?   ;; true if the patch is at the intersection of two roads
/ e. s. f& u0 \5 u, f4 G  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
  x. Q- n! \, C4 S, k                  ;; false for a non-intersection patches.: J- ~3 o6 I5 V. a1 j+ S7 u
  my-row          ;; the row of the intersection counting from the upper left corner of the
7 a7 q) q4 ?8 q. T7 d                  ;; world.  -1 for non-intersection patches.
( {5 i- Y) b6 f' N  }  my-column       ;; the column of the intersection counting from the upper left corner of the( E0 o) D( W6 g+ M. r
                  ;; world.  -1 for non-intersection patches.
, o3 K8 J2 O) s" z! Z8 ?' q  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.% B: L3 z5 ~& e# `1 k
  auto?           ;; whether or not this intersection will switch automatically.
0 ]9 ?! k5 C! @% _; I  F                  ;; false for non-intersection patches.* B  G4 w, g" f
]. D, i% C3 Z9 a2 Y) l

: h! Q; {8 `2 M& r- @2 n1 f) f# y( D+ J
;;;;;;;;;;;;;;;;;;;;;;
; }+ K- c( Y* O& F" A& d) I" }3 e;; Setup Procedures ;;
) c0 U0 w- W7 j2 g;;;;;;;;;;;;;;;;;;;;;;
! `; d4 U: C* u) z8 S
$ v+ T  S) D3 F' o;; Initialize the display by giving the global and patch variables initial values.8 G1 {/ I* ]6 A, x: Q+ c. d7 q* x
;; Create num-cars of turtles if there are enough road patches for one turtle to# F; c; C  z0 @
;; be created per road patch. Set up the plots.( w0 Y2 }* N+ [5 T6 h) C
to setup. A# X# H- U( p- h6 d0 q/ j+ v
  ca: }8 T  v/ R. h# r3 N2 b# N: p0 G
  setup-globals+ X( R4 [- h# O  `. m  l6 m* K0 ^

5 C  I1 }0 E4 k' I( U: c. Q  ;; First we ask the patches to draw themselves and set up a few variables
. O9 J! q+ Q& W" `. }  setup-patches) d: o7 g; c* Y' m, J! A% X$ }
  make-current one-of intersections
" s8 J# l* L* _* ]' W1 Z# Q) _6 h  label-current& R! E( ^3 }4 t- \  ]' V

& P, ^0 ?" m8 a8 [. S2 N  set-default-shape turtles "car"
7 a" }" j# a5 ^2 `3 @, L
+ n3 R. f( U! U  if (num-cars > count roads): A6 o8 s/ N  g+ \- }
  [
: a0 I. @" D* W# w, e    user-message (word "There are too many cars for the amount of "
/ i4 a# i/ b+ s8 F) h, q% O                       "road.  Either increase the amount of roads "
5 y+ P  m5 o4 v7 p- ]+ a                       "by increasing the GRID-SIZE-X or ". o& K* d% ]6 ~2 @/ I  i
                       "GRID-SIZE-Y sliders, or decrease the "2 _& n8 R5 \! d8 a4 M3 {4 z
                       "number of cars by lowering the NUMBER slider.\n"8 M- _. I( T. ~1 ]) i, n& P
                       "The setup has stopped.")
$ Y* |2 s) p  I! m! v    stop& N: @' l% k1 r3 [; p
  ]
5 k. X/ M9 s0 f  E: S' K- ~  w, `4 ?6 _7 Z
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
3 l, X3 m* u$ X' N7 Z6 ^  crt num-cars6 s  ^  W' s  t+ n' [8 v& w0 d. J* L8 c
  [
: e1 ]/ M9 k, x* E4 Z    setup-cars+ A4 q9 T& w0 L8 q( `
    set-car-color2 r# W+ ^- k, p* a! y( Q) [+ U& I4 X) Y
    record-data
7 s" ~2 ?/ Y7 A  ]
9 L% X+ E9 O7 [1 |
2 b' u; T7 a$ [7 a( R" V  ;; give the turtles an initial speed
' h  f) P: ~& d  ]# m  ask turtles [ set-car-speed ]
6 E, P; O) D5 p: |- y! G0 p$ o% ~9 f
  reset-ticks
/ Q$ f5 U! Q6 A0 ^* [# ^# Pend/ v3 c* m3 V% i. z' ]( g; [

! u& H2 v: R" v- R/ r;; Initialize the global variables to appropriate values
( j; R9 O/ v! c* y5 ^to setup-globals
; r7 G# `1 Z! q0 j9 M, v  set current-light nobody ;; just for now, since there are no lights yet
3 r7 g1 U4 |, M; y# L( `  set phase 0
: e- B. h, l, i. r+ ~- t$ Y# |  set num-cars-stopped 0
, Q( S9 R) W. q2 O  set grid-x-inc world-width / grid-size-x
/ z7 E9 a8 @& m# u9 n0 I- R* _' s  set grid-y-inc world-height / grid-size-y6 G3 _$ z% k1 _1 M6 u4 ~# s
4 Y" N5 B# S7 D0 j% x: Q* D2 W
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary- b+ k/ {1 ]( f2 w2 g( M& y
  set acceleration 0.099+ M9 B9 L& a, Z( B( B' r( W
end
6 f) d$ f0 ~0 r% t. e0 Z# E
6 G: T  v: m/ a9 [;; Make the patches have appropriate colors, set up the roads and intersections agentsets,7 r8 |: p0 E0 d6 S5 A
;; and initialize the traffic lights to one setting% d) m' y* r; f3 W" o( |
to setup-patches/ S  B- o% ]" ?
  ;; initialize the patch-owned variables and color the patches to a base-color
9 N+ I+ Z1 f- w  ask patches! o. ]  W7 ^% P7 q7 @5 c$ {9 o
  [0 L! z; b8 M! M; O, C! o
    set intersection? false) s4 u" i2 `5 R
    set auto? false: W! S" m, n  q5 s( p: i
    set green-light-up? true; M& [& C; E4 K' W- Z8 ^# I
    set my-row -1- J) O" |- u! v) P7 Z
    set my-column -1+ l  y' m; {' y
    set my-phase -1
4 G# F4 \& K+ C9 N+ e    set pcolor brown + 37 y# D  K9 U/ @- }' ?% A+ l
  ]
* j: ]" i$ k/ E# _; ~7 T8 y  o; q6 @# K: b; K0 o
  ;; initialize the global variables that hold patch agentsets3 s; u+ L6 H2 u' A9 S* v
  set roads patches with, G0 D6 O. ?! b9 r/ e3 \
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 G# }3 |' @+ K1 Y
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)], d! K4 e* m9 A6 W. @: v9 C
  set intersections roads with$ U) J4 k. E5 ^! c4 B3 }
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and. R. {* e  A/ J5 j3 D/ X# j
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 s: x" G0 U* d2 ^) S, g2 i6 g4 T& j9 U
: E% x) G1 \* `* i, M) {
  ask roads [ set pcolor white ]5 p! Y+ \  G: c5 l
    setup-intersections* Q% {& |6 K1 p2 F; \
end
  _# D! A( P. Q$ u( G% Z) Y其中定义道路的句子,如下所示,是什么意思啊?
- P, \2 P) Y  _8 G: F& G set roads patches with
. M& S* a( F6 z3 c2 z4 q! ~    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
  ?. c3 O. P! X9 Z" t( v" c    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" T: h# ^; Y- C0 |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, 2026-7-21 17:50 , Processed in 0.018361 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