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: 8826|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。
* s- D! x' z* R) O( _netlogo自带的social science--traffic grid这一例子当中,3 y* k% k* L& w. `
globals7 J# S; u$ G& }0 _- y) G' Z4 {' }6 {, {
[9 h2 k: [/ ?, c, c% `
  grid-x-inc               ;; the amount of patches in between two roads in the x direction% x- n2 o" ]- j3 _; v# y4 o6 V) q
  grid-y-inc               ;; the amount of patches in between two roads in the y direction
7 c7 b- B; U9 j; f5 _- T# M, v  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
  j' ?- C+ l' M" y' }, H0 z                           ;; it is to accelerate or decelerate
. @- @+ ^( c" Z" D- a; l3 ?  phase                    ;; keeps track of the phase3 z/ c* u2 k: m
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
/ G" e( F' z2 B. S# F  current-light            ;; the currently selected light
7 i$ S* z3 w' _# y" }0 w, A
& u4 g/ D" ^4 y% P7 J/ ~. T  ;; patch agentsets
- X4 s& m& h, P" o9 @  intersections ;; agentset containing the patches that are intersections
! g! d5 u5 c/ y  roads         ;; agentset containing the patches that are roads
0 w$ Y5 h- T1 E# L- Z]0 P& b1 \0 J2 n7 S1 ^: N; B  _
* M2 F( i" e4 c# P; x( P% H
turtles-own
2 }4 d' C5 W' [2 r' e[
# k1 B9 q$ J* w/ D- F3 B, j  speed     ;; the speed of the turtle
/ p* m7 A* O( Q$ n8 h1 o  up-car?   ;; true if the turtle moves downwards and false if it moves to the right1 Y0 x8 c. K" W- v) ]
  wait-time ;; the amount of time since the last time a turtle has moved
1 ^, z1 ?$ J: e0 l2 Z. k]8 R  X( j8 p$ L* f0 s( V. r
9 Z' D0 d3 p9 Y1 G& G/ }( E
patches-own8 p* B: F# ?& w8 m, j4 O: e8 d
[% i& o5 b3 B0 p! c% e
  intersection?   ;; true if the patch is at the intersection of two roads
# r# T) X8 K8 |- n# G/ ]' k  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
, P) L/ U+ _, z9 s                  ;; false for a non-intersection patches.
% m$ C" _5 N7 Y5 y% M9 I1 l  my-row          ;; the row of the intersection counting from the upper left corner of the7 v5 n, p4 F4 A$ A- a( R
                  ;; world.  -1 for non-intersection patches.
; A" D3 N- M, \4 K- V7 q" c9 F  my-column       ;; the column of the intersection counting from the upper left corner of the$ C. J/ e0 d- q$ ]. ~' X
                  ;; world.  -1 for non-intersection patches.# Z7 X$ `( P0 k
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
5 L+ b3 S3 v' Q) z+ U8 N7 m  auto?           ;; whether or not this intersection will switch automatically.+ w/ ^" L) j; J7 y, l5 F
                  ;; false for non-intersection patches.) A' C0 q5 N5 G. n& Z6 ~6 `
]) x, E! x1 H+ }' E' A

% ^1 B4 q! W7 O+ z7 f; d0 j3 t1 i( ^9 H+ V0 F& y; o
;;;;;;;;;;;;;;;;;;;;;;; ^1 I4 I( w! b9 M
;; Setup Procedures ;;
7 D- x" ]/ n- r/ T  V& v;;;;;;;;;;;;;;;;;;;;;;3 F0 w9 b  Q& s4 ]$ t1 m' S

6 Z3 l1 F3 L# r  S% V;; Initialize the display by giving the global and patch variables initial values.. q0 g+ [  s0 I% L) ^) T
;; Create num-cars of turtles if there are enough road patches for one turtle to7 s3 r0 A- O8 X/ ?
;; be created per road patch. Set up the plots.
3 P  o2 u3 O4 \9 Nto setup
" V1 W: a* ?. g9 l; Y7 t% i  ca( Y/ O( E3 J5 P, ^5 `' K
  setup-globals- d  t3 h2 B5 N5 y
; `! W; v3 G! g# ]3 Q
  ;; First we ask the patches to draw themselves and set up a few variables' f9 f* x5 ]( f$ \
  setup-patches
" _. j* y1 @: V% u  make-current one-of intersections
. N' `/ D( ]) t! i4 J3 G  label-current, a! r9 f2 |% g/ i( n
2 ~9 L$ I$ E# F5 m
  set-default-shape turtles "car"
, R; C7 x- W" l4 c2 ^' |  N1 n- I0 f% {2 v
  if (num-cars > count roads)  e/ ]; M: W9 D/ Y- j
  [
$ p0 Q6 i+ @- i& K! E' m" ]    user-message (word "There are too many cars for the amount of "
0 G  s3 V& u; |/ a                       "road.  Either increase the amount of roads "
. u- n2 e$ Q& f# M/ D                       "by increasing the GRID-SIZE-X or "
% Y. j% k" ?; `4 ~                       "GRID-SIZE-Y sliders, or decrease the "
( G3 S- ?( C  Q% b/ k! f                       "number of cars by lowering the NUMBER slider.\n"1 h- ]. n8 i" B4 D5 t$ [  Y
                       "The setup has stopped."), K2 q5 @7 e! q$ X- H: Z! b! O
    stop- J2 D* k& K# T' H0 w
  ]: H1 P1 ^& S# ^! ~+ p

3 s  H7 K8 _. `, R* X  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color( ~1 x  F% \. Y
  crt num-cars* W; E0 ]/ m4 c- T- s7 o
  [( \. C# H7 r1 V
    setup-cars' u$ k4 g( G0 @% [
    set-car-color
: k) }$ T- {0 `. O. v* j5 v    record-data
) J. R; L/ T* S, ?2 M$ ]# |8 M  ]$ Z6 `2 j  g  @' |5 ~) t

. v2 C& N7 k, j; h  ;; give the turtles an initial speed
9 T& ^4 n. C/ W  ask turtles [ set-car-speed ]5 n5 o4 ]/ @4 w4 V% P
, A* {* t" I2 `- _$ K9 C
  reset-ticks
$ N$ J( v; Z9 N8 m4 a& n6 Nend3 d7 y. O  Q0 {3 G/ K- s) U
4 A3 L' }  r2 ?) F9 J0 K+ H
;; Initialize the global variables to appropriate values
" v* Q: \: w7 k2 S/ ]# ~! b4 Eto setup-globals8 P6 x5 b8 v/ ?( N3 N/ S5 O4 I& N
  set current-light nobody ;; just for now, since there are no lights yet
- X7 K# H3 B2 W4 x- {1 k  set phase 0* }/ n: \- a' w4 [, M  Z
  set num-cars-stopped 0
+ d( F  d5 w6 B2 p  set grid-x-inc world-width / grid-size-x$ H) e, B% U4 V6 \+ j
  set grid-y-inc world-height / grid-size-y0 y/ {. K" x5 t* Q% I

( O% O1 N# V/ C, c! M* Z3 r  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary+ a6 `8 [$ Q2 g  r0 A- q* z& ~
  set acceleration 0.099' m( b' j. R  M" h
end
8 _* s$ A: C' b* Z1 t) e# m! {: e
$ t* g! i6 A' b) L;; Make the patches have appropriate colors, set up the roads and intersections agentsets,& M+ R$ g% V- h# y
;; and initialize the traffic lights to one setting
4 a# m" T& ~0 |+ {9 U& @, y" S" eto setup-patches
+ f, q/ s7 f7 C3 x' U* }- Q3 w  ;; initialize the patch-owned variables and color the patches to a base-color) J+ @) N  ^( ]! Q- T/ n
  ask patches
: c; `3 F' f+ L& q' j- ]  [1 q; h& \5 e8 `! V: V
    set intersection? false1 ]7 c6 F/ B- t  E4 b1 \# o& `
    set auto? false
' a" ^" O6 P- @! e5 k7 d2 j) s    set green-light-up? true1 B4 t. c/ p: _! u
    set my-row -1! l4 j/ f# u. G
    set my-column -1
8 P7 V9 C# Y$ E$ c  c    set my-phase -1* ?# ]4 K: O4 u' A3 P, t, p* t. T
    set pcolor brown + 37 `2 @% U4 R# T/ B+ i2 i
  ]- t3 p( U5 D$ {  r& n0 |
5 p2 k( J$ @9 L. v. w2 H% b( Z
  ;; initialize the global variables that hold patch agentsets
7 F- T5 K. M3 \8 x- }8 p  \  set roads patches with
  R# |7 D7 m" V5 a; B& w/ e: R( w    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
1 W, u3 _+ K( N/ M( T$ F" |    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. ~7 V/ `, u/ ~- V  D* c3 y( K/ n1 P
  set intersections roads with" b" m6 O2 s# ?7 e
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and, M5 F- H& Z8 |$ H2 L
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 m+ H. z' O4 y/ @/ Q% p9 R8 C# T
- w5 U! e' n* G5 G7 R7 U  ask roads [ set pcolor white ], M' Y" E; L9 b% L+ l. f; h
    setup-intersections9 v2 W+ A% N2 m9 A& t  B0 n& A
end
& k( o$ U7 \3 X8 v; _+ W3 R( t$ d其中定义道路的句子,如下所示,是什么意思啊?
: A: {# @# q1 i# s" i set roads patches with
6 _/ L& ?2 a2 {4 N! f! M    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- W/ e2 A2 J) t2 \" d3 }* L! I
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' k0 j- s6 b4 E) T: \! G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, 2026-3-11 16:13 , Processed in 0.018037 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