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: 10648|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。; N2 H  y7 q9 K  Z
netlogo自带的social science--traffic grid这一例子当中,
0 B* A5 Q  K$ P& J, pglobals
/ E6 z5 I, \; L) t( t[. [/ i( T& N/ D% X. j2 e: c* O
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
$ z. |6 n! s6 u0 _6 ?, o! L  grid-y-inc               ;; the amount of patches in between two roads in the y direction' |) S+ [6 M! l" `" x5 e4 J
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
3 G0 O3 K7 |+ X8 i* I                           ;; it is to accelerate or decelerate
, h. W: U8 S0 }  phase                    ;; keeps track of the phase6 [2 n8 R3 _$ ?4 S6 T
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
. y3 W4 t9 h0 e% E  current-light            ;; the currently selected light  w- s- y# b3 {5 O. ^& t
$ c4 Q$ _) Z8 M+ x8 m
  ;; patch agentsets
# G6 [) x( w/ K" H! _7 X- `  intersections ;; agentset containing the patches that are intersections
; u3 z+ d8 P! o* ]- V# @, J! G5 i  roads         ;; agentset containing the patches that are roads9 E$ a" @+ I& T* U7 B2 ]# H
]
! s* P0 K* F: P# X! |. [+ T' [. p/ {1 ?
turtles-own
( o% z' Q) b1 H( \" Y* ^[8 [0 h# V5 r1 _8 E  G
  speed     ;; the speed of the turtle
2 W7 V; ^  s! P3 z* y% \2 r9 @  up-car?   ;; true if the turtle moves downwards and false if it moves to the right4 F  W0 w/ G3 s5 I5 M$ V8 B
  wait-time ;; the amount of time since the last time a turtle has moved, l$ f5 b  U% ?% B4 A: y) Y# I
]
; c% H& z2 t+ w* p/ x  }$ _. V  I3 Z$ ]" i" [( S
patches-own
" H0 G& A4 W  {, e2 u[
2 Z% a/ ^, y0 ~3 S. i2 F8 G  intersection?   ;; true if the patch is at the intersection of two roads. S* e' S1 f  X+ ]% V
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.$ n2 s) E) v3 d+ L9 M: m8 g
                  ;; false for a non-intersection patches." _  }# x5 u; h2 X( n, a
  my-row          ;; the row of the intersection counting from the upper left corner of the
3 r- e" E# C) t6 ?# O                  ;; world.  -1 for non-intersection patches.
+ }7 m3 o/ s4 p" L, S  my-column       ;; the column of the intersection counting from the upper left corner of the: o" w1 z! X$ y: R2 E% z
                  ;; world.  -1 for non-intersection patches.
8 r* c5 P5 L- u; T* u! t  ^( i  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
# g7 {3 x( v3 ?. B8 X/ K. G0 H  auto?           ;; whether or not this intersection will switch automatically.
5 b* j1 X& D+ n                  ;; false for non-intersection patches.
, P3 Q% W/ i6 c/ J7 ^$ b# K]1 \- J3 i7 Q' M* r) b* `0 a) y& y
* V: [$ ~3 E# k/ u; n3 b& m

: }; o" s7 d/ C* K$ F;;;;;;;;;;;;;;;;;;;;;;
& R  p- F$ B/ x% g: ]# k, |;; Setup Procedures ;;
( Q5 h3 t2 |8 x: d  F3 Y3 \1 Y;;;;;;;;;;;;;;;;;;;;;;
" k3 m6 Y. [* p, c0 s; |% b  Z! b* {. N. o1 Z6 D  |
;; Initialize the display by giving the global and patch variables initial values.
& O: a* Z- k4 m* J7 K* y;; Create num-cars of turtles if there are enough road patches for one turtle to6 ^% C2 J" Q1 i! T0 H& o3 n: H
;; be created per road patch. Set up the plots.
, C6 B& n" ?9 A) fto setup
0 W0 _2 s4 r* n5 O% }9 x  s  ca0 F* H$ F6 |; \
  setup-globals
- g2 d7 \5 P# h* B5 d! C! L7 Y" r3 p5 |% Z, L
  ;; First we ask the patches to draw themselves and set up a few variables" \# Z( |' D* P0 @" Q
  setup-patches; K5 I, _7 Y* O* m
  make-current one-of intersections
1 Z  }8 I1 o8 v( m6 P  label-current
5 s" {3 c, y3 Q& U" Z& H, @5 N7 I
  set-default-shape turtles "car"' `/ p+ R* b, w; y! T
; o: s1 ^" `' h! k4 ~
  if (num-cars > count roads)
1 g; \* p. G. f0 Z1 @" W9 y  [( {* B+ A0 w/ ^7 |9 J5 u) R
    user-message (word "There are too many cars for the amount of "
) H/ G8 j, Y. x# Y6 O: M                       "road.  Either increase the amount of roads "' g5 ~! X! L2 S* I8 j
                       "by increasing the GRID-SIZE-X or "
+ z  E1 Q. C9 ^3 g0 E                       "GRID-SIZE-Y sliders, or decrease the "# W; G* y7 D5 o$ G  U
                       "number of cars by lowering the NUMBER slider.\n"
; O# @( }- P& E/ |8 t                       "The setup has stopped.")7 m3 L: \* z( D0 [7 \
    stop
1 J7 `: Q) k) v+ f1 f. H' f7 F8 H4 i  ]
- ?: N5 {3 w0 r
1 J8 q% n$ ~: \1 {* c) Q" D  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
9 Z% F2 l0 m: Q$ A3 q  crt num-cars
4 x& w# t9 i' m  z; E  [
- G+ b6 |' z! c+ X    setup-cars
+ r" z  s. S, G0 H9 }    set-car-color9 n+ e# s0 U# Y: S) Y( M+ g% K
    record-data1 g4 H% t8 [, W7 X
  ]: `3 z* x8 S) ~( _
  Q2 v. x  T4 x8 J# x( e* t
  ;; give the turtles an initial speed
- L3 N4 d4 j' v$ x2 `' b  ask turtles [ set-car-speed ]2 S9 p8 V  b: Q

+ e0 [  x  H' @3 T  reset-ticks$ {5 @/ G& u/ E9 \5 S
end; d0 t5 V! t& f6 I3 f. p* l

: s( d! q* N* A;; Initialize the global variables to appropriate values3 J2 p/ S' h) q
to setup-globals
6 ?! N5 r, O( U( l- c  set current-light nobody ;; just for now, since there are no lights yet
- f& Q( \0 W$ B9 t  r  set phase 0
7 i1 x9 A3 O6 n$ X$ ^" }; Q; l  set num-cars-stopped 0, X2 B% ?" L4 D# r! p
  set grid-x-inc world-width / grid-size-x" W/ V" a. M$ U) _
  set grid-y-inc world-height / grid-size-y
' {; V1 F2 K+ |# o7 j+ T: V2 l
* v5 x5 v# @9 Q, D, G  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary/ U5 X9 n. f( H$ G
  set acceleration 0.099
, ]2 {( t5 G. h0 L& e! Qend
7 b, q! r/ r& U2 ~3 ~# S3 V# _' s) e+ [
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,! j' l# V  c7 C; X
;; and initialize the traffic lights to one setting2 L( g! [8 d- N; \
to setup-patches
7 s) U1 p3 s/ z1 s+ G* i  ;; initialize the patch-owned variables and color the patches to a base-color
3 I" V" Y5 v& P4 w3 L. W  ask patches0 i1 z) K8 J+ }0 L6 n3 X9 [
  [- R3 x) z5 b, f6 v6 f
    set intersection? false
8 W9 v; j2 ]% `2 I! O3 T    set auto? false* B1 X+ x0 a$ n7 \. b0 W5 h
    set green-light-up? true$ @5 \( |: ~/ a5 `
    set my-row -15 Z4 G' j) T/ a& o0 e
    set my-column -1
, b$ j+ C( d* y0 Z7 h2 r    set my-phase -1& s6 e' ]  l$ u+ D' a5 b2 W% {
    set pcolor brown + 3" x" f9 O3 e' g" \1 V* j. \1 v
  ]
% r1 Q* }/ t" ?2 e; b
5 v& K1 x7 N7 n" c2 u- F: g  ;; initialize the global variables that hold patch agentsets
) w! H1 N% I! c& n  set roads patches with9 j6 N+ I! y- |
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 ]" a" n! q4 b" d    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. j( \# Y" J) Q  M  set intersections roads with- p! f$ q' C. F7 Q+ ]5 `+ b
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
4 J- _6 G; K9 m0 D. b6 l5 c+ R- v" R    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 ?; Z8 |' W0 [' s) `( r. _. f; |
  ask roads [ set pcolor white ]
% M: u9 t+ T9 f/ ^$ ]' m, t    setup-intersections
9 w: O$ `  }, Y, Qend
! `+ {$ x1 O" r$ s: M其中定义道路的句子,如下所示,是什么意思啊?4 z0 U$ |6 ^, E" O+ T( N
set roads patches with
0 p- V" r* _/ p5 A$ H- o5 h# x& v    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" B. m( r! N# C8 a
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 r' u6 k2 b' G7 u4 F4 b, N
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, 2026-6-17 19:48 , Processed in 0.014264 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