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: 11690|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。4 l( G- M/ }! S- X9 c/ D  F) o5 S$ @! b
netlogo自带的social science--traffic grid这一例子当中,
$ R: T" E* [2 o6 S. ^globals" B2 l5 |- h; |& Q# X- _, Y. u1 C+ W% V
[
/ H) j; ~2 y1 K' P7 I/ N  grid-x-inc               ;; the amount of patches in between two roads in the x direction2 f8 i; n" E! w& N. X
  grid-y-inc               ;; the amount of patches in between two roads in the y direction4 L, t- h# e' D6 q) |
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if: l" i# F; R+ N" [7 O" c
                           ;; it is to accelerate or decelerate: _8 Q" n6 p5 p" T% k
  phase                    ;; keeps track of the phase3 z( Y* F% s$ g% h6 E& v
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
+ P7 s' }0 \( P/ a3 H  current-light            ;; the currently selected light
% F' x) q+ N! F* z5 ]/ D6 C; h( }% w( h
2 o$ O' z8 |2 X% \+ Z& n  ;; patch agentsets  R/ t5 v  [& C7 f: C2 ^* S
  intersections ;; agentset containing the patches that are intersections
: k7 Z; _2 q% h/ {0 v+ p$ o1 _  roads         ;; agentset containing the patches that are roads- f! k3 X# `; B8 [, k/ T% \
]% R$ }! o/ W5 d; \9 Z1 ^3 ]

7 @9 c8 w9 u7 J3 Nturtles-own
2 f% i; }3 l" p3 e9 s2 k0 ?$ h[
7 Z( A3 C2 x+ ?2 l  \  speed     ;; the speed of the turtle* M# Z3 C0 T: x: K- e
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right3 q( A+ b$ I; X' r8 C. V5 f7 u
  wait-time ;; the amount of time since the last time a turtle has moved; A$ c$ b; V' W. `
]
9 j4 G+ R! L" K4 D% ]+ g2 F7 s2 C) `+ ]& R6 g9 M7 s# P
patches-own
2 b9 c  Y  w$ ^! _% h[, c4 M& a# X1 @0 q4 n. l1 v: T3 m
  intersection?   ;; true if the patch is at the intersection of two roads% P6 R/ H8 i  e9 Z9 J$ \& m, O
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.( L8 [. t' s4 P& p. P$ g0 h* J6 V* ?
                  ;; false for a non-intersection patches.
4 L6 `7 p8 _' C1 L4 _  my-row          ;; the row of the intersection counting from the upper left corner of the- R' n0 R. x1 H, z: l! o
                  ;; world.  -1 for non-intersection patches.$ z0 v# b& z, \: ?. O. p8 D
  my-column       ;; the column of the intersection counting from the upper left corner of the
* k+ P9 l. l! J! U# e) x+ R                  ;; world.  -1 for non-intersection patches.
# c" t) B3 R( w  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.' W, G; v& D9 s+ P) ]" h
  auto?           ;; whether or not this intersection will switch automatically.- i: [$ N! S3 G/ z5 Q5 V5 M  J% H
                  ;; false for non-intersection patches.
& u1 @1 C# _0 ]6 t5 f6 []" Y- [- r- J, S! h' m

$ x/ |' B4 g. f4 o' I2 B
: w- @7 D( z- S' b, k5 X: q;;;;;;;;;;;;;;;;;;;;;;
6 F: R: L! R, ?* @;; Setup Procedures ;;) v) A- l" ~) N6 K5 a6 b
;;;;;;;;;;;;;;;;;;;;;;
4 X$ l* w% I  B- w% Q7 v, Y) C/ n  O
;; Initialize the display by giving the global and patch variables initial values.
- V% T1 E2 E% W- C! H  E;; Create num-cars of turtles if there are enough road patches for one turtle to
: c/ E  C$ @/ W/ T3 l& ?;; be created per road patch. Set up the plots.- b2 P7 Y  L! H: s3 Q/ h7 H
to setup$ d# i! A8 @5 m3 \
  ca! X. p# a9 {. z  F" g% l
  setup-globals
# F' h& ^. f+ I, ?- d9 \
3 R! I4 M' |2 f0 H, R  ;; First we ask the patches to draw themselves and set up a few variables
# v  J9 K, F$ j; @; g" H  setup-patches
; p' Q& P& I4 x+ T4 X( _  make-current one-of intersections$ R6 C" r+ y/ v/ c# i
  label-current
8 Z" S' u7 G/ x
% r1 C0 _* ]8 e* ^  set-default-shape turtles "car"$ U; e6 |) o# X7 J( x: F# `/ ^
3 ~9 }: Z% l) ?3 u  O( g0 l. A
  if (num-cars > count roads)' m3 i+ H+ `* c$ j& n' v8 \- M, B$ ]
  [3 |+ h( z9 j, z, C0 {$ Q- y/ g
    user-message (word "There are too many cars for the amount of "
( H" M! \" }2 U( I                       "road.  Either increase the amount of roads "% @0 U2 r. ?  A
                       "by increasing the GRID-SIZE-X or "
! X, f" R- n- D# `4 W$ X" N                       "GRID-SIZE-Y sliders, or decrease the "
  x, o3 m/ c2 |3 m; z( x! ~; z1 X* [                       "number of cars by lowering the NUMBER slider.\n"
" ?+ @. B& A, k# o1 E                       "The setup has stopped.")
* {+ }6 V- M$ u1 ]    stop4 J( K0 W$ T) ?; m' `$ g5 Z
  ]
. a" J5 Q5 C! P- B
& B2 L: H+ ^6 k- O9 O# d; D  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
+ \& ?3 h. ?; s, z9 l7 Q. m' P  crt num-cars( ^7 Z9 c: Z4 @$ _/ I) F' G
  [
% W5 V' |' z1 J9 `; }& W" X    setup-cars
2 Z5 `* g+ D4 c9 V0 f( f4 u! ]5 Z    set-car-color
" K  C6 j6 L2 Y    record-data9 W. D  S( c) h  W0 m2 f# R
  ]6 ], E) h& L3 |+ w0 w# g
1 S+ V' z- d7 a' D) J
  ;; give the turtles an initial speed
  [% U' e, L+ X( d* U  t  ask turtles [ set-car-speed ]0 w4 ~7 ?/ L) z6 }1 `3 M& ]
* L& i* w+ k2 o- z' u& F( {" C
  reset-ticks6 p" Q9 i" d+ K4 X/ p" H3 T
end: B% I  R# V- a( X! F% ?5 R  U

/ x" [' g1 e, g, E, t;; Initialize the global variables to appropriate values; T1 l" N, `( E# ~$ ]% D; W
to setup-globals2 b* h+ ]* S9 J
  set current-light nobody ;; just for now, since there are no lights yet
2 ^8 a( E' O8 X* s- A7 s+ H' t  set phase 0
# n" y+ s- O5 U/ Z) F  set num-cars-stopped 0
6 r( M5 c4 o+ j' B9 ~  set grid-x-inc world-width / grid-size-x& y7 Q& S2 i4 P; Z" I
  set grid-y-inc world-height / grid-size-y
9 [1 t* M0 o  O; T. J1 S/ p9 h0 w* R
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
; V8 V% Y5 y. t9 f- P  set acceleration 0.099) o$ j6 L- t( F+ a4 E9 }. \! w& o
end) S% s2 d$ T( Z' O2 ^' u, ^* m
, k% \# M4 m8 [/ s
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
1 [. n1 m2 A) S1 g% ~' T5 g;; and initialize the traffic lights to one setting
  h) a- S* S' i* x# x, Dto setup-patches+ w- i+ O. l/ W2 t3 j( P% S9 J
  ;; initialize the patch-owned variables and color the patches to a base-color
3 B0 o- h0 X2 m4 t* B' l" ]  ask patches
- p" J+ x8 u8 N: @) O* y  [
0 H6 O, p8 e7 P    set intersection? false
& j% e" K, M0 A0 z    set auto? false
- N8 F( t- c% ^; e& x( K    set green-light-up? true. Q7 X' c4 t6 N" x
    set my-row -15 Y- z$ T! o! h
    set my-column -1- b* J% T/ J* o3 `8 l/ D
    set my-phase -1
8 J. N% s4 ~( F" h+ Y- N    set pcolor brown + 36 ?5 e4 I- o0 S  n7 {1 ^+ d" m# q
  ]
9 ^/ P' E% ~4 K
8 r. L3 |1 g) {7 _' ]/ ?  ;; initialize the global variables that hold patch agentsets/ M" f* i$ b" {  _$ T3 R4 u  V4 ^( [
  set roads patches with! C$ ^8 p* i2 U, n9 S
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- f$ b& [$ B' ^+ v( [
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 m: i8 @- {' H  v9 g' s1 [4 U6 l
  set intersections roads with! T  U2 [0 d% l5 D8 i5 h! H6 r
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
2 J9 f& W: V7 h$ W6 r    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]  q: \4 b% ^7 q" }7 s

% J$ P! O7 k) t5 B  ask roads [ set pcolor white ]
. \# |) y* |' |3 _4 {3 H    setup-intersections+ I4 H, C/ E% R6 n) \2 C
end
0 S& c, ~( R! ]( r  ~; }$ E其中定义道路的句子,如下所示,是什么意思啊?
, `1 |3 x, F; O4 a( B! n set roads patches with* B8 @3 ^1 r$ v  ]( T& A
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% }0 C3 k5 ^! }    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% V: \, y/ K* g$ w/ {- w
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, 2026-8-10 23:17 , Processed in 0.016105 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