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: 11805|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。7 n( Z- V, g+ ~7 ?6 Q1 G# E7 v
netlogo自带的social science--traffic grid这一例子当中,
( q- @5 e0 _/ c. r& \globals9 s6 H" [7 R0 D4 g( |; B
[
( o" x, b8 U3 I- m' \  grid-x-inc               ;; the amount of patches in between two roads in the x direction# c- i/ G% O# h6 h4 _- a
  grid-y-inc               ;; the amount of patches in between two roads in the y direction
6 E% m% _+ q5 u/ ~8 j# F  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
+ R' r, K$ @/ V0 r5 b                           ;; it is to accelerate or decelerate
: n9 Y( n( m! I; @  phase                    ;; keeps track of the phase7 c: c# @) p: ^* W+ H7 b7 E
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
% p% @9 v, s; R# z7 Y* n  `  current-light            ;; the currently selected light
/ \9 y& p% H  J& D1 p
' G& k9 S1 X1 g! ^' \  ;; patch agentsets* m% H8 `$ K, u, H
  intersections ;; agentset containing the patches that are intersections
. N1 u% v7 u! Q4 x( c0 W, S  roads         ;; agentset containing the patches that are roads- t  x: M! ]4 R/ N; Z# _' D
]' s$ Y6 b+ Z4 n; S. X3 u% z( X9 j

5 p3 e4 B7 _2 ~! q: hturtles-own7 S  q* {% H  @" j
[
8 z- b( B0 U; S2 Z  speed     ;; the speed of the turtle
, q3 ~& D* U8 ?% P  h; C  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
/ |+ N& U4 K0 K  wait-time ;; the amount of time since the last time a turtle has moved/ V2 J6 ?3 f& T
]+ }- q2 t7 T6 \* t8 X/ e
, ?8 v& h! }5 ^
patches-own
, F% ^0 S$ ]9 O# u5 u( j2 q[7 C) P9 Y+ m% z; Y$ |. L
  intersection?   ;; true if the patch is at the intersection of two roads- s* x3 k$ G# c) n* c
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.0 R1 n* B4 j" W, x8 o5 o% P
                  ;; false for a non-intersection patches.
  \9 D4 E) z. i$ u  b3 b+ _  my-row          ;; the row of the intersection counting from the upper left corner of the
' F/ y' s) S% Y* C                  ;; world.  -1 for non-intersection patches.6 d; I5 J. P" ?
  my-column       ;; the column of the intersection counting from the upper left corner of the
- a+ E; T* i2 K                  ;; world.  -1 for non-intersection patches., y+ w$ ^4 ^1 S! k( D3 h
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches./ {' w0 V3 a' x) w+ v8 e: _: K
  auto?           ;; whether or not this intersection will switch automatically.
, a6 f2 a8 e( u9 d                  ;; false for non-intersection patches.0 {. r, i/ j5 x( J; A
]0 G0 w" d4 D/ u" M6 i: z# G2 L3 ?
1 ^# Z; u) l' \

. t" e% T+ A; h3 @0 g' p: x; n;;;;;;;;;;;;;;;;;;;;;;4 i: x( p2 {4 q. p0 s% |: a
;; Setup Procedures ;;" T8 r( U5 l# w- }3 t, y# Q1 {* C
;;;;;;;;;;;;;;;;;;;;;;
4 x5 l" O$ x& K
1 A- H" c& q. [/ r0 w;; Initialize the display by giving the global and patch variables initial values.
. d, E- E: n, z# S  v;; Create num-cars of turtles if there are enough road patches for one turtle to& P$ q/ }# B! }6 L/ a9 h, D
;; be created per road patch. Set up the plots.# A, I: \# Q0 }: l  f
to setup# ~+ o( M1 _- A( s- s# L
  ca" w/ @3 E+ _6 ?6 i: \$ h6 O% |
  setup-globals! d) T- v7 }2 f. F

" ~# V# G) |  O8 b. y  ;; First we ask the patches to draw themselves and set up a few variables+ _/ g4 u" n( N; U
  setup-patches7 M: A0 y& K  c; V* W
  make-current one-of intersections! E4 V7 s0 |2 g) v( M
  label-current
! f3 x& s# k: Y6 u# M
4 W8 J  ]1 K6 [% J2 A$ \  set-default-shape turtles "car"
+ }3 d( F. j4 L  d! Q/ f4 {. ?4 W* K5 v- c
  if (num-cars > count roads)
6 T* Y: N0 b3 E9 U+ q% d& {  [
+ Z, N3 d) Q* j    user-message (word "There are too many cars for the amount of "
, c! d+ T. ^$ t/ y                       "road.  Either increase the amount of roads "1 ~" ~+ K" e# X6 x3 v$ |
                       "by increasing the GRID-SIZE-X or "3 Q" k2 ]" |/ U9 C# i; q2 w
                       "GRID-SIZE-Y sliders, or decrease the "- h  E* s  S* [9 Z3 c
                       "number of cars by lowering the NUMBER slider.\n"5 n4 M* I4 T- _) q" c& o6 H
                       "The setup has stopped.")
7 l. U- ]; Y7 {' r    stop
( [  Q/ q: B/ O' \' \" E+ m  ]' I: i2 k  z5 W6 ~9 `4 O* m

4 J* P8 X- Q) S1 l  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color3 q) G/ y( ^! F" u9 c+ L
  crt num-cars# A8 q9 d. ?7 X" F& F$ U, j4 S
  [0 V  v: p+ o/ P' B6 Z/ d
    setup-cars* ^1 u& O& r+ z
    set-car-color
% U  z- ]/ z9 R& i3 Q; K# k8 W& i    record-data
, r7 G# N( ]# c1 i; I' S  ]
$ B( z9 T  K4 ?: W' r
9 _/ k+ ]- S9 l# y1 G" y; A. O  ;; give the turtles an initial speed0 _) o( y' b* J1 F3 x6 ?3 L9 q* {
  ask turtles [ set-car-speed ]
/ q# I" O# ?1 K  U6 s! T9 p
. B- h4 ?+ `( l2 X4 N5 U* n  reset-ticks& ^/ q; i+ k- R5 ^7 D4 I% n
end6 m: ^8 T0 n7 E1 p5 A- ]

" n8 \; ~  R; Q" S: B5 {! Y;; Initialize the global variables to appropriate values4 S5 e9 s( F* Y4 e5 A  K+ D3 a: a
to setup-globals
  O2 L9 g! b; P/ C# ~3 l) v3 ]  set current-light nobody ;; just for now, since there are no lights yet' p+ J* A- c1 ~' ^: O) C8 L
  set phase 00 @! K. ]: P% F$ w% q# H* ~
  set num-cars-stopped 0) A+ y/ P  A( n' H
  set grid-x-inc world-width / grid-size-x1 N$ }' ~0 M" G4 v( ~1 H/ n
  set grid-y-inc world-height / grid-size-y& `1 j9 q4 m- p1 ?! B
% n9 s: S6 M  r. \. Q1 j3 ]
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
/ @8 r+ `7 x9 z& m" h  set acceleration 0.099  E- b. C0 P! O( u8 \- j- O
end2 M' T) n8 ]% j* e* v! R" r' L+ `

, S: n2 d1 V7 B, v" ~, D& o;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
1 T3 z% s2 R) ^# k;; and initialize the traffic lights to one setting
9 g$ h9 Q, v2 a3 W( ~: t9 Fto setup-patches1 `' [& Y( ~/ Q! p5 S. L' r! |
  ;; initialize the patch-owned variables and color the patches to a base-color
8 l: b$ |; s5 W% W0 T  ask patches* T) q8 G5 k6 v% C7 A' B
  [
' `6 C1 [1 b  B7 m- x: \. V: J/ c    set intersection? false
8 o7 z- [* J  _9 Y6 i) L/ T    set auto? false7 N+ B6 u8 g- u! f/ N3 L% T1 e
    set green-light-up? true5 X' \$ Z6 R2 I9 p6 ]
    set my-row -1
, A0 @% R- t2 j    set my-column -1) K# }0 [5 S+ k9 e" ]
    set my-phase -1
9 Z! Y$ M4 e6 Q  y7 P- r( y: Z# ^    set pcolor brown + 3
, k4 d9 u' `- K6 J( C8 o3 [  ]
$ L* N4 t2 z& n$ }* O1 K* B: N: p& Q
  ;; initialize the global variables that hold patch agentsets1 z( t  f" x. W! P/ T5 j& K- h% w
  set roads patches with  k2 `, p1 f6 k" w
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
  L) }8 d$ R; H& i( b  m( S    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
7 V! Q7 V6 ^& U% K  set intersections roads with/ {) z. W( ~0 W/ U" m# m
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and+ k; A  B2 B8 {. _
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. {3 }* B$ f+ V8 F- W- G- [
  n  y. J( h  c5 K* d1 m5 d, [; I$ B
  ask roads [ set pcolor white ]% L1 `$ @& q  C. H* X  K+ l
    setup-intersections
" B+ b# D, j5 y$ L& l2 Fend: _0 L  ~% m+ V0 M
其中定义道路的句子,如下所示,是什么意思啊?) G6 B0 m) Z+ B8 s
set roads patches with) U. C9 F5 \6 k4 G4 T
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 ~* P0 B, C  O
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' x% T) X- V; I. m+ q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, 2026-8-17 23:05 , Processed in 0.020757 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