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: 12056|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。, B& g% Z5 s3 q% U: C) r
netlogo自带的social science--traffic grid这一例子当中,# K0 C  J  ?6 r2 Z5 G
globals7 ]3 I5 T1 a) U& T( Y8 [
[+ v& {8 H+ d4 @: Q( G# ^& e2 f
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
- V$ ?- R1 b% ?& R$ H" p  grid-y-inc               ;; the amount of patches in between two roads in the y direction) A+ v; H/ v' Y9 a1 ]
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
7 T1 [% M. y2 h; {1 k                           ;; it is to accelerate or decelerate
0 C& k4 z& A8 m- W  phase                    ;; keeps track of the phase" ~3 G* J8 A, Q' D
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
% j# ?6 I1 B+ H2 A+ _) U  current-light            ;; the currently selected light, t/ \4 j2 z+ O" ~3 h) \& g  _

. X* H" w$ z: p0 @3 E5 ~7 M/ s) n* ~  ;; patch agentsets: ]* l. g0 ]$ x6 @! `! F* U
  intersections ;; agentset containing the patches that are intersections& J1 X& t, \/ e% J, y. H7 c
  roads         ;; agentset containing the patches that are roads
+ M4 [+ ]* P' b' C" {' ^; J% n]/ X3 ?1 }/ g, k% [6 m( }3 a
' F; J) o- r) b- B
turtles-own
- S" O* z: c, j: R$ O, [[7 `0 J4 T3 ^3 \: g1 s! @$ |+ E
  speed     ;; the speed of the turtle& C; q) f2 C( Y: g# o9 Q
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
) E$ z5 |% @' s  wait-time ;; the amount of time since the last time a turtle has moved0 Y2 A5 J0 o7 i
]5 o/ Q- v2 u# u  o

3 U' \2 x9 F) Vpatches-own0 g8 N! p7 F* c) C+ a
[+ {' M8 b( W& G$ p; o
  intersection?   ;; true if the patch is at the intersection of two roads
  Y; J( [  E/ o8 @  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.- @/ u% a* }6 d8 a0 F" j
                  ;; false for a non-intersection patches.$ u$ B& U! o' N/ t& J8 T4 I( }- s
  my-row          ;; the row of the intersection counting from the upper left corner of the
. v! U6 k/ w, S( [) @2 Y' @                  ;; world.  -1 for non-intersection patches.! T! W/ b+ C7 o' S* w4 _8 H
  my-column       ;; the column of the intersection counting from the upper left corner of the
' S& ~, o& B5 V7 s; A' T1 K$ \                  ;; world.  -1 for non-intersection patches.
( `/ ^, G' L' \! S6 J0 c" s" @* l$ a  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
# Z3 |( j. b7 w, k: t8 f  auto?           ;; whether or not this intersection will switch automatically.' C. v5 \% T) _3 H8 y1 X) U
                  ;; false for non-intersection patches.) v9 f' e2 f$ g" H: @. n( c; }
]
% W; Z- H8 e$ F" B
; x  ~. B7 q! v% b% o. M' C- z. [% R6 _  T6 R! L. L: S
;;;;;;;;;;;;;;;;;;;;;;
( o0 c. w5 p7 Q6 l3 f. Z;; Setup Procedures ;;
0 u7 s2 `1 I1 D! ~  n" P4 a;;;;;;;;;;;;;;;;;;;;;;
) ~2 Y! F9 D8 j. H
. z6 A9 C* o/ j. y* E;; Initialize the display by giving the global and patch variables initial values./ a3 e/ c; N# s
;; Create num-cars of turtles if there are enough road patches for one turtle to: N. C9 Z. z8 y, d
;; be created per road patch. Set up the plots.
- B9 f# V2 g9 ]$ z9 M, Pto setup- y9 ^6 d5 f9 e
  ca1 ^% `$ z0 t( g6 L8 H
  setup-globals, U; i$ g2 z8 |5 C

9 R" D4 \4 F2 }' L4 c7 b- z' C  ;; First we ask the patches to draw themselves and set up a few variables
& Q% C3 c; m& }: n' ~  setup-patches" L* r# K- }! f1 U) f7 `/ c
  make-current one-of intersections
* y9 M7 G' X+ w; r  R  label-current
6 ^. U" C% U# h. n; Y+ \- D- R. u3 S+ n; j3 T2 o
  set-default-shape turtles "car"& w. C) i1 O+ V- e" q7 R
, j& x' O  Q: p% ~1 M
  if (num-cars > count roads)* z9 l" D* R& u7 j  o% c
  [2 w9 Y: |/ g2 c* H5 E8 z7 G7 A
    user-message (word "There are too many cars for the amount of "/ {6 l! h1 d2 n& o7 b
                       "road.  Either increase the amount of roads "% K/ W4 _) j) N, k  w
                       "by increasing the GRID-SIZE-X or "- b( }% i3 }8 o& m; k4 i
                       "GRID-SIZE-Y sliders, or decrease the "
# w* R$ [$ ^4 t1 W) _; o# u) z                       "number of cars by lowering the NUMBER slider.\n"& p6 n' L0 {$ S1 D# L+ j8 ?9 F
                       "The setup has stopped.")
7 p. M2 h+ l) z) Z! ?# i1 x* r" S    stop
- p7 z$ ?' v" b( O$ k4 F  ]8 [: y  |* H1 E4 C! E9 f9 N

# C1 f9 |3 ]( f2 U  c) y  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color. h, g" k& @- `  |. ]
  crt num-cars
* u- l8 V: J9 ~  [
  F* s2 O8 p& m; P1 V: C    setup-cars
4 t/ q+ a7 l0 _+ U9 G$ Q; z5 K9 T    set-car-color% I9 _+ `  l% R- @& Q
    record-data: c% X" w. y& D
  ]$ i7 B( @6 E) c. K

8 A5 m: h# B% F* v* L, T  ;; give the turtles an initial speed2 [. O9 `; ~; S& n
  ask turtles [ set-car-speed ]
; `! V5 p0 s6 _9 l9 I* s" E6 z. J4 X" t$ [( P
  reset-ticks
) V+ L' r/ e) nend* U$ w4 u& h, Z  G

! e' w4 b' r6 R' _4 C;; Initialize the global variables to appropriate values5 I  F% R7 A! P: _+ p! S
to setup-globals: D8 ?# {( o4 U- p
  set current-light nobody ;; just for now, since there are no lights yet
( e7 _; j0 K; Q. L& R8 n: `6 z  set phase 0
8 ^3 J6 x+ D/ z6 [& @  set num-cars-stopped 0
+ Z0 s. v4 l$ B& o( B7 B# r2 ?: c  set grid-x-inc world-width / grid-size-x, [+ k3 E5 e1 e; j; {# l. b) x+ b
  set grid-y-inc world-height / grid-size-y3 T2 Y/ Z* T# w/ R

$ F: z7 B# e; R$ n7 d  u7 R  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary/ O4 ]5 j, _8 ^+ p9 Q& O0 }; W
  set acceleration 0.099
( O! k3 p3 M) R3 ^* ]6 p. B; Qend
- w/ `6 A; C  k; ^- j' y! y0 M% z3 b/ A3 ?* i4 o/ _; T4 T) A
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
6 A( A) k' d8 u& y; J; x' |2 y;; and initialize the traffic lights to one setting
" C. [! s2 o. H) Q5 O$ |2 Dto setup-patches
1 ^' k5 j* q3 N" B) T  ;; initialize the patch-owned variables and color the patches to a base-color; w9 T, r5 X  e* `
  ask patches
% C3 J" p6 q* ~9 f  [
$ W( _" t, z6 T8 S* L. n    set intersection? false- i2 R9 y8 O) h' n: `
    set auto? false
% s+ N* V' @$ ^8 s3 W3 T, `    set green-light-up? true- d+ O+ H4 h( i3 ^- t% {% t
    set my-row -1& g6 i* n9 \' e3 B. F5 I( ?
    set my-column -12 ~+ B: c! r% D; D
    set my-phase -1
/ s7 j9 q. J( i1 s    set pcolor brown + 3
( i* D+ m+ d1 b2 \0 f: r& \  ]/ B% A# z! h" [3 |0 h6 U. u
0 [& F1 V, v: O  S, n
  ;; initialize the global variables that hold patch agentsets  k0 `; }$ ]' d6 P  @; Y* M. S& T! x
  set roads patches with
$ m; d- k& P+ Z- L" K& D, p/ L# G    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& ^, i; a/ _: q
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 d% x( ~% ^9 ^+ a) r  _5 ^  set intersections roads with, K- r2 K( ^# o; v% u9 Y) q# ^& I3 ]
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and' Y5 c' v4 U8 {1 q
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 B* a0 O. U% W$ d3 ~0 A: v/ P5 ?2 w. T* }" w: {3 b* i
  ask roads [ set pcolor white ]6 Z8 h: {4 ^: U  L# X9 [/ x
    setup-intersections
2 t, I) \4 y7 b* [0 send! B/ h& ]# [7 ]* A. P3 C% {1 h: a8 {
其中定义道路的句子,如下所示,是什么意思啊?
. S' r! O! m7 G2 S" ? set roads patches with
8 V/ v# J' N7 M$ w! N/ m! u1 ?    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 @" i2 h" @- p3 J$ s4 l
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 i6 W! {( ^/ @- n$ m& v' F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, 2026-9-1 18:25 , Processed in 0.023342 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