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: 7380|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。: Z3 c2 u4 o- u3 v
netlogo自带的social science--traffic grid这一例子当中,
: J2 Q, T5 _4 u5 R. ^9 `. o- N+ rglobals7 A8 X' |$ f: E' S/ x- h
[
& _5 K/ H6 S8 ]/ f3 n" F  grid-x-inc               ;; the amount of patches in between two roads in the x direction
: y% e) s4 z' k) I  grid-y-inc               ;; the amount of patches in between two roads in the y direction
1 u6 ]6 ^: i6 J3 S5 i  acceleration             ;; the constant that controls how much a car speeds up or slows down by if2 C8 H! b+ {/ L. y: E* u0 M
                           ;; it is to accelerate or decelerate
' i2 N* ^5 U) z% W/ ?( \# ?  phase                    ;; keeps track of the phase
; _  U4 J1 b" N) j0 i! T  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
3 S$ i" h& j! f7 C" @0 r  current-light            ;; the currently selected light
* O  Q2 P4 {- R3 D9 t! k" T: S2 X8 O8 N; }4 I6 D+ t* e7 }) u! \% m: Z* h% w
  ;; patch agentsets
3 e! G3 x" q9 o5 s  intersections ;; agentset containing the patches that are intersections  @. i7 H( L* j) @. k
  roads         ;; agentset containing the patches that are roads
+ M$ u+ m) J( P) P% C) A2 p]  |0 |2 L$ S" q! c5 D8 Y

* L; d7 B9 E6 h5 Aturtles-own
) C+ ~: H/ w$ f8 b! L[1 T3 ^' F( {; U( G8 h) u
  speed     ;; the speed of the turtle- u$ F8 P4 L& @* |# `
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
# t5 [' x) `; M5 h  wait-time ;; the amount of time since the last time a turtle has moved, J, L0 S/ p7 C2 S0 l. w
]  \7 ^* Y$ b- y  t9 T& t& L
- A: x* s7 ?3 z* L, O8 p
patches-own& A, |: Z7 W, q
[) G# O' h' |* C! s. J
  intersection?   ;; true if the patch is at the intersection of two roads
9 A9 z4 o- r6 h+ |# Z+ `  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
& n" I0 O* ?( C. H! T1 I* k2 L- b                  ;; false for a non-intersection patches.- U; w2 B8 l5 @9 E
  my-row          ;; the row of the intersection counting from the upper left corner of the3 i8 U; a1 |# f" k5 `5 x
                  ;; world.  -1 for non-intersection patches.
( y1 }" {  Z7 l/ s; ~  my-column       ;; the column of the intersection counting from the upper left corner of the; l- [0 }3 I6 s3 y) I9 l+ C2 q
                  ;; world.  -1 for non-intersection patches.# ~* b4 }, s) s4 X
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.' j" }  @- g* S# L
  auto?           ;; whether or not this intersection will switch automatically.) S5 Z. n, t9 C' T  j6 |
                  ;; false for non-intersection patches.+ `. K& d/ q! _2 v
]# g9 R* t- }* F* _$ Y  h/ [2 T" e
* e8 ]: [& x# i/ ]5 e4 L
2 M9 c9 g- U- i
;;;;;;;;;;;;;;;;;;;;;;
0 B/ i7 ]* e$ Z;; Setup Procedures ;;9 Q% Y9 F$ g! g2 B8 c) K0 k% h4 ^
;;;;;;;;;;;;;;;;;;;;;;
7 L8 z  v/ N( k& ?4 _) I; O( v" z# A
;; Initialize the display by giving the global and patch variables initial values.$ D( }, ^& \" C. O  i
;; Create num-cars of turtles if there are enough road patches for one turtle to: @) i7 {' W9 N! _
;; be created per road patch. Set up the plots.
$ `1 ]% S6 L  S% wto setup
, m; _- Z, y9 Z1 Q0 g  o, R+ Y  ca& y6 J) a4 F) A7 w
  setup-globals
* e0 Q5 [4 {* Y6 y& [; v% x3 x' {4 {/ o0 [. h3 e
  ;; First we ask the patches to draw themselves and set up a few variables
, n2 n: \, E$ K( z0 M  setup-patches
# u$ [6 L5 w! x3 A  make-current one-of intersections
- K/ w* r1 f' Z' p7 F  label-current( v" g4 `* U$ Z6 L; T# O* ?& m7 u

+ Z2 c: B5 T2 [/ a' ?  set-default-shape turtles "car"
3 b9 M% E) Q4 |" q( {0 o- t- i, y
9 t3 P9 M9 F5 P/ j# j) W0 u  if (num-cars > count roads)2 i# H1 p) F; @
  [
6 u/ Z; G* x- n; d    user-message (word "There are too many cars for the amount of ": T2 R9 ]- w( D5 d' p* U( O
                       "road.  Either increase the amount of roads "
, W* B4 H: i# d6 Y1 L                       "by increasing the GRID-SIZE-X or "+ K$ p9 g+ i% Y
                       "GRID-SIZE-Y sliders, or decrease the "; m; ^4 N& ]) N5 [' E( S( k
                       "number of cars by lowering the NUMBER slider.\n"
6 o( j) s9 b( [& Y8 a; }                       "The setup has stopped.")
/ A) e/ [0 u: l, u6 k/ y    stop) }8 b4 `" g. l; H
  ]& I) g" s' @, {3 A" {7 R

' m' H) k; v& ~& m4 A5 n/ b2 Z  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
; y) \' m7 h! L4 r+ |4 c2 W0 E4 Y2 r  crt num-cars
9 H! e! U" m. b" u  [
6 s- }6 X! t* ^  @: {7 w    setup-cars1 M9 w1 ]! g) r; A7 n% q1 m" q
    set-car-color
  L9 W: L, U! O6 J% W" D6 O    record-data& }# y7 e3 D( h2 d8 w0 v$ [, l
  ]  b0 D. V& {( {

; o, r% E6 P+ J4 {  ;; give the turtles an initial speed( y3 t0 Y- q% c2 x4 g
  ask turtles [ set-car-speed ]: t7 _6 |' Z6 ]7 [; t; n: Q4 _
1 Z# A4 f$ K* g7 @
  reset-ticks
9 l- X  Y6 q8 c9 n" }/ n7 |5 Aend+ s9 }: N  M2 B$ a  V" t4 b
5 y" f* {4 X! ?. b1 z
;; Initialize the global variables to appropriate values
% q, ~5 a- B8 R2 C0 Vto setup-globals* d+ u4 S6 C/ c/ e, m; p! ~
  set current-light nobody ;; just for now, since there are no lights yet
' E- J, Z5 L0 \6 d  _/ k  set phase 0
% b. _7 C3 `( U4 Q  set num-cars-stopped 06 _+ j" x% ^  m; Y% A6 A: ^
  set grid-x-inc world-width / grid-size-x
2 \7 C3 K5 K8 {1 t9 q  set grid-y-inc world-height / grid-size-y) O' M  D5 M& g* D  L2 w3 S
, `# Q& l2 ~' i( f- U6 d% X$ m; p
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary& O& }( u$ F& ^/ J! D/ i
  set acceleration 0.0994 H! ?" B: {0 L% u4 B$ n
end
# y# k/ w( d& }" [0 |7 Y
, c9 T7 a( a, ?* ^3 q% v/ U- R;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 f* B- f* z$ _' n3 R;; and initialize the traffic lights to one setting. g) I/ j3 p$ ]% p; Z% T+ K
to setup-patches0 L( o$ e# j# s! L# `7 E
  ;; initialize the patch-owned variables and color the patches to a base-color
7 N( F3 ^, a' a5 k) [, y5 G* `" @  ask patches
6 W5 {2 g+ Y/ o2 v  [
2 L) [! Y4 p% l& J    set intersection? false2 I* p/ y1 V4 f( O" a$ z; t. _8 I
    set auto? false! z/ l: u9 {! s* B6 T9 ~1 p+ K
    set green-light-up? true
7 ]! m& X+ x0 J+ v" h* `6 S    set my-row -1
* q2 H: ?  G2 O1 t    set my-column -1
4 w6 W2 ]3 u/ C2 I    set my-phase -1$ d! L: v1 [4 H
    set pcolor brown + 3
2 o& E4 m$ I% g, |! s; m6 `  ]
9 k8 h/ h* Q- r$ Z
+ _) Z  ~) n9 N1 I: z. \  ;; initialize the global variables that hold patch agentsets
0 q; K3 {" C, E4 `+ d; ]" X  set roads patches with
0 z2 X/ \6 d  k3 \/ K( e    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ a5 Y0 |, |# l7 W/ I9 r- R    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- m8 \& R4 D; ^  set intersections roads with
6 p  `; A- V( v( A    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" |' P: P  W" H1 E, [0 r, L    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ x8 f& `4 Z* o2 |9 C3 `
& ?/ j7 U+ B- O. x
  ask roads [ set pcolor white ]: H5 I9 K) E. Q, b0 q6 i7 U  P8 j* O& n
    setup-intersections7 d+ i# [; n1 U6 b$ a+ ]
end
) n% ?0 S- `/ t# n, ]. }其中定义道路的句子,如下所示,是什么意思啊?
/ b( b( B/ I1 }( ~3 y set roads patches with* C6 b0 n4 n7 v. J: b5 k
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 C0 a) ~9 U2 t) y  R    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* {/ N& [3 u1 _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, 2025-12-12 03:21 , Processed in 0.016060 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