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: 12196|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。
- n) f5 r. \% _7 N$ Hnetlogo自带的social science--traffic grid这一例子当中,
' b! s% D# j5 S& `: gglobals
/ Q! C7 K! b: s) y[
6 M9 y1 _! P; Z2 D  grid-x-inc               ;; the amount of patches in between two roads in the x direction
4 w5 x0 S1 ?" z" d( j5 c# e$ P  grid-y-inc               ;; the amount of patches in between two roads in the y direction
4 o$ p7 q. {, t# [7 I0 s  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
5 _; o2 r: u+ T5 j2 n" ]                           ;; it is to accelerate or decelerate. ^- w1 @) o5 v
  phase                    ;; keeps track of the phase8 u5 b' c: x, N, u0 c
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
7 |& r# v: {2 s0 F. O  current-light            ;; the currently selected light9 a) h. i6 E5 h9 l3 t% V1 C
/ W* J* m- F5 \8 l
  ;; patch agentsets: G6 i/ Y/ \6 U
  intersections ;; agentset containing the patches that are intersections7 v$ Z* J, @: k; K$ d
  roads         ;; agentset containing the patches that are roads
" v% G$ C  T$ B" f/ i" m]; H: K# T& o  v* l$ K, P; i

9 c# p: W) }8 Q5 W4 qturtles-own4 f  J0 u$ v0 S! H5 {, H7 g' P
[: r+ R9 }& L1 {6 @# s7 W
  speed     ;; the speed of the turtle, ?& u& F; `1 K" s" t- P
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right- @  L7 \" J8 g; X, u+ X& d
  wait-time ;; the amount of time since the last time a turtle has moved
& t/ N) R: M/ }% w]
8 k8 l4 [8 e8 k' `# b) G* x2 L" I& @  k
patches-own
/ F; H  Q! t( M# J3 {5 L4 ?[- U0 F7 n3 a/ k9 m) V/ t8 q
  intersection?   ;; true if the patch is at the intersection of two roads0 a/ P5 g$ q4 N
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.; _2 _. x# _' H" i4 Y
                  ;; false for a non-intersection patches.
  ~2 P' u4 ^* U( f  my-row          ;; the row of the intersection counting from the upper left corner of the, p) @6 j  N9 X7 X  I9 ^
                  ;; world.  -1 for non-intersection patches.
) C' _2 `5 {/ `9 E  my-column       ;; the column of the intersection counting from the upper left corner of the
( c$ `$ M# o* m9 I2 J. U                  ;; world.  -1 for non-intersection patches.
! P* X& t# g$ R6 ^( t2 j' Z! ~  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
+ r9 w4 o# z: A( Q  auto?           ;; whether or not this intersection will switch automatically.
3 G4 s( Q+ Z9 g; u( H' V! V. e                  ;; false for non-intersection patches.
& n( B+ ~. A3 Q) i]
9 Q; C: @: {* q5 e
: o/ O" E" S% p1 z% E$ b0 V
  n$ q; O7 q' M; E/ l- s' q+ G;;;;;;;;;;;;;;;;;;;;;;( v, N/ x/ D6 F! m) O
;; Setup Procedures ;;# X- _5 |2 Z% S  t; p
;;;;;;;;;;;;;;;;;;;;;;7 Z" }" q$ i4 `5 s& ^( A: O# U
' H8 R! B9 L4 y9 Z; ^1 H" j4 [
;; Initialize the display by giving the global and patch variables initial values.
; ^2 u2 u1 x" A- k;; Create num-cars of turtles if there are enough road patches for one turtle to
& A% O7 B, E& r* g, Z& X/ R;; be created per road patch. Set up the plots.
; w& f) D4 @) m+ h1 p& ato setup
2 s% _( |' H! m  N' A  ca
9 q) \6 C& j% G# L, J8 s( l  setup-globals
# r4 l1 ?% u/ K: x6 F
+ I3 a) k$ J  `8 {! L$ F  ;; First we ask the patches to draw themselves and set up a few variables
& w0 M- Q& G& C$ A" y: u  setup-patches
$ M0 H' b6 Z& d( ?2 Z, y' {  make-current one-of intersections1 V8 V- [+ D: s0 V& X5 K8 w
  label-current
1 S8 N# ~5 P; {- K# u. _
4 i' n3 t  Z+ h2 _$ F8 Q, b! M  set-default-shape turtles "car"& W, t) T5 G+ F

0 i- r$ Z- u. H  u2 g9 G  if (num-cars > count roads)& K2 w6 J2 F4 ?# }; J; O
  [0 U  k. N7 k2 z! r2 b; s6 c
    user-message (word "There are too many cars for the amount of "7 W& [7 j. Y5 G- q9 M- ~
                       "road.  Either increase the amount of roads "
# _0 r0 _, l( s: C                       "by increasing the GRID-SIZE-X or ", W* F) Y% D1 W8 l9 r! n
                       "GRID-SIZE-Y sliders, or decrease the "
- c: w- M4 D0 {0 P# ?$ ]  T                       "number of cars by lowering the NUMBER slider.\n"
- j, H/ f8 J3 x) |- W" W$ s                       "The setup has stopped.")5 }7 _) o' A. l( p
    stop9 f( H7 A! l. V# k1 ?. [9 X/ m" v- Q
  ]! C* o  o, r. g7 R, I+ k! F
2 T1 i! g! \7 [. c
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, A" d, N$ u/ x# N  crt num-cars
" A' ^% U0 _( ^: `) n' r) I/ q  [4 N  K' Y9 |* S( X* Z' C& W4 H9 S
    setup-cars
0 q- t, K5 ^: G/ V* |    set-car-color
+ I  @; f: l4 }6 ]2 t7 M    record-data
1 n5 Z  h7 O) M+ A  ]& D4 ^8 n( P( _+ D" b% J' k  U6 v
! c8 D( K6 a* M
  ;; give the turtles an initial speed
- {& x; A# m8 \2 S& c0 b- f7 I  ask turtles [ set-car-speed ]4 `" L, p2 X3 I0 j; Y1 O" s

3 g2 h  k+ T2 a8 O. u  reset-ticks
" A* ~% J1 N, d& s- D# ~end8 c; `: p3 R% }$ \1 L

3 |( Z# G# d/ i* q4 o;; Initialize the global variables to appropriate values
, n3 `8 c0 b( p# z! h0 Dto setup-globals1 R- [$ U; W% r% z' V
  set current-light nobody ;; just for now, since there are no lights yet( J" r8 N5 n! y
  set phase 0
9 p3 w0 r0 ?- c  set num-cars-stopped 0
) y6 T) [9 F0 }' Q  set grid-x-inc world-width / grid-size-x
2 q9 t5 G! `. u5 c) X9 m4 y: r  set grid-y-inc world-height / grid-size-y
, ?" E7 _+ X( `9 t4 w2 q3 A% J3 Y  P$ V0 m+ E0 H8 h+ Q
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary) y0 Y& o+ d3 L' U& D2 f
  set acceleration 0.099
0 n& A: M8 o& oend
( N+ N6 b8 |: h1 ~, O6 H( G- ^
& e: f7 f% K0 S. i;; Make the patches have appropriate colors, set up the roads and intersections agentsets,3 ^0 x* ?7 w1 n- z% C) d/ k8 |
;; and initialize the traffic lights to one setting
5 N9 S, Q- b$ P& t, {8 ~+ pto setup-patches
: e$ o7 k3 E5 N% I* C6 t+ o  ;; initialize the patch-owned variables and color the patches to a base-color
# j* J, f( F, n; E7 l, E6 k6 F  ask patches0 g6 H! J$ K# x4 w4 t& [# A
  [+ y3 E8 h% }$ v* X) x  _
    set intersection? false
8 C, s+ N- [' m2 n. g& `    set auto? false  {* p* [# u6 n9 \  [2 {& a2 g1 i
    set green-light-up? true
* I, C; X/ P1 B( Q$ A    set my-row -1
* X$ D! p) o8 S    set my-column -1" I, X/ E2 J/ O) a* F
    set my-phase -1
; ^, M/ V: A; k, a$ t    set pcolor brown + 3& G: x; h, C; Y3 e" y
  ]
& N' H; ~4 a, r3 d- R# Q, _' [  a/ w9 H* d: {6 D8 W* H
  ;; initialize the global variables that hold patch agentsets
6 i) w" e$ }6 I4 m* u  set roads patches with, Z2 y8 H" C( T% k) R7 v
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or9 _4 @5 F3 }& D& s" ^; T
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]! v, g8 ^+ O% f! R' G9 X
  set intersections roads with. x# A, G4 y6 h0 g
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
$ |4 y: Y0 p2 F/ a    (floor((pycor + max-pycor) mod grid-y-inc) = 0)], ]  h: E5 t! z; c

. h( U6 \" I6 G2 F* l3 b0 T& @2 Z  ask roads [ set pcolor white ]( y1 x! ~$ f3 N+ @
    setup-intersections& b. c" W  `$ p5 f, p' W
end
. B3 j: N8 ]+ ~; a其中定义道路的句子,如下所示,是什么意思啊?
5 k. s/ \4 L0 @1 f; [8 m set roads patches with+ N/ P1 f* a1 _) X0 n3 U9 w- F& P
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ V$ X/ T! ?; U+ |    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# C6 K' g# d- }7 m% k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, 2026-9-8 15:04 , Processed in 0.015554 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