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: 11796|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。
; l! l; c8 f1 b, C  r5 g- N; `6 j( lnetlogo自带的social science--traffic grid这一例子当中,
; \: i/ A8 b& r/ x! Y8 F* fglobals$ [" w4 T; m9 o! M0 `$ B& m0 F
[+ w. A  L2 j: b6 H& U
  grid-x-inc               ;; the amount of patches in between two roads in the x direction% [% _& ~9 H0 `9 |  e. j- M
  grid-y-inc               ;; the amount of patches in between two roads in the y direction9 T* d0 u1 Y( X8 K7 k
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if" q. k, X7 Y- R3 I
                           ;; it is to accelerate or decelerate4 @$ G$ }, u) f, ^0 B9 M1 |9 d& C  F
  phase                    ;; keeps track of the phase
0 k% P, @1 z2 W* R  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
: R. D1 C/ X9 h* p5 q* `* e  current-light            ;; the currently selected light& h: I  j- M( E, ?" H- K5 V
7 `8 e) U- M" d; r
  ;; patch agentsets) Z9 s5 ]5 b+ f6 K8 `
  intersections ;; agentset containing the patches that are intersections* N& q% u; C" P
  roads         ;; agentset containing the patches that are roads
" q1 ~3 g! z) I1 N]
4 v8 z; t* S& M$ [6 ~
. ^% j4 A" c. a0 G  a+ Sturtles-own
- Y4 Z9 W, ^6 {8 X1 |/ g[
0 _' v+ i3 U3 |3 f7 J% H4 u8 @  speed     ;; the speed of the turtle
; g, n! E2 O$ V2 L7 Z( T# U  up-car?   ;; true if the turtle moves downwards and false if it moves to the right1 W3 w6 y8 X2 O' x6 U2 h; H
  wait-time ;; the amount of time since the last time a turtle has moved1 O! p( f% d$ Y9 G3 q* U  X
]
# F7 p; Z( l' O* n2 D5 Y0 z! h+ W% M- K: A! A! d; c
patches-own1 {' j; n7 W- `- H, j. G1 T
[/ W: c( v7 y# i0 Q: z0 ]( n" |
  intersection?   ;; true if the patch is at the intersection of two roads
/ m* Z3 F6 N; ~3 N  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.8 o* e6 @$ r+ }
                  ;; false for a non-intersection patches.3 Y- }- p7 L  x8 o3 l
  my-row          ;; the row of the intersection counting from the upper left corner of the
# c; `; X* S( u* j6 W  T7 Q9 q7 }                  ;; world.  -1 for non-intersection patches.
. o& _, T& U7 F- e1 M. E) Z  my-column       ;; the column of the intersection counting from the upper left corner of the
$ k" }- n. f; n/ w/ W; E3 O! k! Z                  ;; world.  -1 for non-intersection patches.
8 g4 a' m5 w8 F* p3 Z. I$ C% |  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.' F$ F' n  b$ I  w! f' {
  auto?           ;; whether or not this intersection will switch automatically.
. Z9 M% U7 e: b$ Q                  ;; false for non-intersection patches.; d7 \) ^5 R+ U2 J9 j8 E
]0 G  I8 L4 O: {8 \

5 o( }, v4 V4 p1 j4 H. J; y
$ S' i- y2 Q# @4 }& H5 y9 N;;;;;;;;;;;;;;;;;;;;;;. _# D( ]5 m) O' y- @
;; Setup Procedures ;;
4 h8 X' }5 w' s) J;;;;;;;;;;;;;;;;;;;;;;
  m8 H) ~( p6 t! g& a/ w) \- @2 k
;; Initialize the display by giving the global and patch variables initial values.6 u) N" D6 o% l, ]
;; Create num-cars of turtles if there are enough road patches for one turtle to, f+ n  E5 V: t  y! h5 O7 b
;; be created per road patch. Set up the plots.: ?* F( G& W4 ^/ ]' G
to setup
% G' d0 c) `  E  ca
! V" O* n" z. H7 D  setup-globals( O* r( R' |2 g3 Z. V0 L2 t/ ]/ O/ e/ _
+ t' |/ T  u, |8 C" c/ a" T
  ;; First we ask the patches to draw themselves and set up a few variables: g0 }6 K% N2 a8 r
  setup-patches' M- P7 e6 D' z4 _4 k
  make-current one-of intersections
7 J% Q8 P/ k5 Z1 f. o7 `% B; d# u  label-current6 G9 H5 P  P  G+ M; @/ R
7 j" F1 }4 T  J7 g( e3 Y
  set-default-shape turtles "car"
- @) w/ G3 M3 y+ T6 T% g$ Z  ?) T4 v  E9 m% ^1 K& {
  if (num-cars > count roads)
, A2 j& r- }  o0 ^( f' ~" T/ C, ~  [
4 d" n3 v  o5 m7 F$ d    user-message (word "There are too many cars for the amount of "$ P7 A& R0 h/ G( f# t4 _; f2 h
                       "road.  Either increase the amount of roads "
9 u9 |( j& X5 ~8 Q                       "by increasing the GRID-SIZE-X or "6 |. s3 Q, \. V6 _/ I, l8 O. I. l
                       "GRID-SIZE-Y sliders, or decrease the "
- G" m3 J; l( ]# W                       "number of cars by lowering the NUMBER slider.\n"
' O  H' ?, t" f% j9 X7 n                       "The setup has stopped.")
. n' x- E6 r( {    stop. t3 C- J: N. D8 O" b. [+ `
  ]( n. Z# d/ ~2 g* C  o
4 B, E  a$ W; s& U
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
6 h7 h3 [4 b1 y  W: X/ m  crt num-cars
. ?: q) C, a+ h6 H3 o9 a1 q  [" [, D5 l% \6 }3 X$ K" o
    setup-cars
5 z* {5 y! g* n, g' ]0 L( E    set-car-color3 t; o6 }3 w6 e* L
    record-data
7 |+ u9 `1 Y( e+ x1 l  ]$ y% Q( `- U1 l# @% j  L. A
, }" d& i+ J1 l3 K
  ;; give the turtles an initial speed
4 I! U1 w& V$ B- h. M% Q2 @$ ?* T  ask turtles [ set-car-speed ]! v5 r" h/ G: U' w; B

5 k% A9 R$ z* A) ^  reset-ticks6 M$ ^4 S8 i# E1 f0 n
end+ _5 D- m  _9 C% z7 q
1 e8 o* l  @& \0 n; X$ Y
;; Initialize the global variables to appropriate values' Q- O, g" v% e8 `' u9 E, K
to setup-globals- w3 m4 S/ O& d+ A  |3 Q
  set current-light nobody ;; just for now, since there are no lights yet& |% W% E" F  W" A# w* u* k
  set phase 0
* b/ I1 W  q" j& \$ ]  set num-cars-stopped 0
% S9 H4 m: Q. |2 N  set grid-x-inc world-width / grid-size-x
9 D  e- y3 o8 u# E0 n  set grid-y-inc world-height / grid-size-y& u9 i+ t- ~; r3 C& g+ S
' G5 I9 d: i& Z$ g8 V1 _
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary% R  [& j1 P  F  Q  f
  set acceleration 0.099
. j% I4 G' y  d5 ]  }end  z% S( K! ]( R* Y: ?1 i% g

5 K5 O0 b0 {* X/ e;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& [1 F$ l: z1 X8 @;; and initialize the traffic lights to one setting
. P8 e# Y9 ?- N7 U' \to setup-patches. `3 h4 P; V$ l
  ;; initialize the patch-owned variables and color the patches to a base-color
) M" W8 D' n- s7 T# G* D  ask patches
. S# o0 j2 p8 a$ x6 G) [5 s  [4 r4 y8 ]& k; W! o- j
    set intersection? false
- X% I/ _( s9 D9 L5 Z! J    set auto? false# h7 p# e5 l& ^! r
    set green-light-up? true
( q, ]* W+ u: K& B    set my-row -1) |6 Z( @9 G$ b$ [1 h8 ~
    set my-column -1
% k  K/ c6 C; `3 `    set my-phase -14 G/ y8 E2 o7 T
    set pcolor brown + 3, i$ E3 X4 a* m5 ^& H6 C
  ]& [, m: E6 {) s+ y6 r
! _3 l. B& ^- O" v' ?
  ;; initialize the global variables that hold patch agentsets
) ~" R9 `- t5 e, n! h6 v6 R% C+ Y* `6 v  set roads patches with
# W% R" F0 l% E& K    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 l+ u& E) T# h7 S- T  @" ]    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
( d5 {' r% C( L8 }/ c8 j7 i  set intersections roads with
7 M' I- q& G, S4 X+ g9 r# r    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! F6 p5 e# D9 l
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* Q1 I0 x5 B5 ~2 u1 \1 t9 u- a. i% Y' O/ ^* R" K3 \. R- ~
  ask roads [ set pcolor white ]
+ k( R- d& ^, i/ I, d    setup-intersections) y2 ^" R/ u9 l& L
end
. U; R% v& v( [其中定义道路的句子,如下所示,是什么意思啊?
# n+ v) r9 O$ V6 j/ _) v2 y set roads patches with- ?2 ^5 e0 B' ~+ l- }3 q
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 U3 `3 p9 w" Y" D- a6 I/ ?    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. k& _. V; F, A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 08:43 , Processed in 0.019027 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