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: 11956|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 r' U) V- n3 Q: u0 Hnetlogo自带的social science--traffic grid这一例子当中,6 {* r( r, C6 v9 J2 d
globals2 w4 R2 m5 C0 G! D
[! J0 v' T3 T2 d" F
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
( v; Q. m- L" X4 G+ e/ O  grid-y-inc               ;; the amount of patches in between two roads in the y direction
5 v) [8 C- u9 i  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
9 [" b! \7 D9 i% C$ F/ `1 ^                           ;; it is to accelerate or decelerate* [) Y' n. q: ]! `
  phase                    ;; keeps track of the phase
, Z, S3 F& l) w! v( A8 x* e0 [2 _  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure2 m) T  _$ r8 T: ?4 |& B9 O; V
  current-light            ;; the currently selected light+ s9 w* y' p; ^8 u
) q* X& W3 h/ E; i
  ;; patch agentsets! x* K% y) k7 \' O
  intersections ;; agentset containing the patches that are intersections
$ w$ B% L/ h5 ]  d; ]! |8 @8 K  roads         ;; agentset containing the patches that are roads
4 Y) @: x& ?0 t% J+ n) b" h' H]
: u# U1 S+ v9 ^% x. |; z* a/ f  r" \
5 E" |/ h" s: O/ l5 S9 V" Pturtles-own4 O, c  b1 z% G, O
[
4 e3 J7 A1 Y1 u) M  speed     ;; the speed of the turtle! ?; `3 j1 g' N2 D* a
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right# z; Z, m  i3 U) U8 W+ e: }% i2 ^6 ]
  wait-time ;; the amount of time since the last time a turtle has moved1 L+ k6 Z9 Z7 r; l
]3 t3 a% w1 I' l

5 L! P3 M) y+ E+ E: ^# ^1 K) Apatches-own8 ]; ^0 o* A* b
[
* N, E& Z! a! j1 W  intersection?   ;; true if the patch is at the intersection of two roads" n" O- \) ~, q0 v3 h0 @% B
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
4 m7 K6 o- F& }) u$ S/ z                  ;; false for a non-intersection patches.$ {  I9 E7 Z) r4 U" t) B
  my-row          ;; the row of the intersection counting from the upper left corner of the' Y& r% O1 [+ h- g
                  ;; world.  -1 for non-intersection patches.. Y$ d. g, e! x6 O! D
  my-column       ;; the column of the intersection counting from the upper left corner of the/ Y& H: a$ X- K
                  ;; world.  -1 for non-intersection patches.
+ I' |0 o- g1 O7 z/ x% z" e0 l8 t3 T5 M  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches." O7 Q1 m' Q; C; f8 W" C& R; e
  auto?           ;; whether or not this intersection will switch automatically.
' f  h; Z# M4 L9 p( }                  ;; false for non-intersection patches.! q2 A  S: z* u8 C7 U  U9 p3 i
]
$ i' I: Q7 Q6 F% F1 E  [; y
7 I0 @1 i3 f0 d9 C. Y
( q" \0 }/ ~8 x. n" R4 k;;;;;;;;;;;;;;;;;;;;;;; R  s8 a; ^4 [6 d' y% R
;; Setup Procedures ;;- G% N; C4 ]( O. a
;;;;;;;;;;;;;;;;;;;;;;
  e' w1 x# E8 T+ W+ f3 d
( Z5 l8 G6 x1 c+ P+ C, Q8 t. w;; Initialize the display by giving the global and patch variables initial values.
0 a$ w* V% W" U# {& k9 N;; Create num-cars of turtles if there are enough road patches for one turtle to
* C- M1 K6 g, g" m! B1 y;; be created per road patch. Set up the plots.* f0 h, S3 C" A
to setup
9 f/ Z) a; `6 h* x- ~: `  ca# [- D8 K! K/ `/ p0 w9 ~
  setup-globals7 ^% _8 ?( S+ V" g" B$ z( m$ Q
- |( _* ?. B7 P0 b- _' s! q
  ;; First we ask the patches to draw themselves and set up a few variables% l- [6 D4 j6 @* j6 M/ l
  setup-patches1 F" w/ z3 D2 N/ U; x- y4 F
  make-current one-of intersections# k  P( h8 c; w! m6 H
  label-current" n& H7 r. w' u$ @: ]/ S

; ^& F1 ~! |' V  Z+ G  set-default-shape turtles "car"6 a( ^1 y% k5 M! Z0 v' Q& {
* m: k5 T1 P0 z2 K) Y: ~( {* T7 }6 n
  if (num-cars > count roads): A/ B+ J0 s" i7 E
  [5 i3 Y. p: L7 C! U6 n
    user-message (word "There are too many cars for the amount of ", c  L8 g- L. t$ t% H
                       "road.  Either increase the amount of roads "' b" z" B* ^: H! d2 ~( Q+ ~
                       "by increasing the GRID-SIZE-X or "  W' j. Q, B( ]3 O1 z
                       "GRID-SIZE-Y sliders, or decrease the "
0 y- v6 X3 Y3 K1 P/ h) U! z4 F                       "number of cars by lowering the NUMBER slider.\n"
/ U: W% Q" K  y# Z6 i                       "The setup has stopped.")6 E/ _% j" g$ d: g
    stop
$ i, p2 B$ L" c  ]# j9 _2 A3 S' ?* Q" b- K
) i7 O5 b6 y" S& t$ B* A
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
$ G! e/ |% Q8 I4 e  crt num-cars. N7 @+ X. O/ j/ v7 r* z( o2 q
  [* q2 S3 k+ f* K
    setup-cars3 G6 Z" y$ G; ]/ S3 L; \
    set-car-color
) e. K9 C' b7 z8 T% q    record-data* q& Y5 v4 w7 p  x  s
  ]: q$ R, O1 F! K
' K5 z8 O& h: @; G; {* ~3 ~* b
  ;; give the turtles an initial speed/ m  O1 l8 [3 j) X8 X9 A9 q
  ask turtles [ set-car-speed ]
/ t* s/ Y5 y3 a8 a, }$ ]$ z, t
  reset-ticks
% r) h* @+ G8 }# J7 @+ a7 \! N# eend
( d3 I9 m2 Q0 s( h5 |/ G+ H9 b: k% L+ w8 G2 r
;; Initialize the global variables to appropriate values# t8 d, i& O/ R+ ^1 j
to setup-globals- k$ T. O& B& ^$ I
  set current-light nobody ;; just for now, since there are no lights yet
7 I! B# c' C3 T4 f( g  set phase 0
- Y$ e/ Z* e" h: z" @1 d2 D0 B; k" |# U  set num-cars-stopped 06 [' e. z$ d' n  Y2 N; l. J2 E
  set grid-x-inc world-width / grid-size-x
9 j) W7 a) G. r( n! v& F  set grid-y-inc world-height / grid-size-y. t/ H9 C/ Q$ P7 ~6 Q1 P. S

' R% y9 x; [6 h& B3 V  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
0 x5 Z9 l# {- u$ i% S$ a  ~  l  set acceleration 0.099
3 B( Z& @1 B* l( S6 Bend
6 J) b7 l+ ~8 D) w' u9 e; [, O3 d+ P$ u; W
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,; U3 R% X" ?$ F4 F; k* _7 ]8 F
;; and initialize the traffic lights to one setting
3 v# j( I( W0 g9 [. Y; v" Jto setup-patches1 m6 e7 ^0 O7 m* J4 f
  ;; initialize the patch-owned variables and color the patches to a base-color
" R+ O7 e# v! M( Y  ask patches
( c, p- M+ `7 F5 {  [
3 ]7 {) c" N9 a) P    set intersection? false
/ F# b' }6 K+ B    set auto? false
: @# b) y0 q3 U' q; f( W  U    set green-light-up? true5 L% J& l, @3 f% R* C1 F
    set my-row -1
- s, O# o) j7 T; o& x* H# w    set my-column -12 ^, Z/ ]* v( a* W- R* U
    set my-phase -13 \6 \) N) i, X1 l: Z. Q- H% v( X
    set pcolor brown + 3
3 Z& r! \* y0 h% ?# l  X  ]
3 g* \& }& j* L$ h5 |( |7 |( W4 R3 z
  ;; initialize the global variables that hold patch agentsets0 [( `% r- U1 P" g# R
  set roads patches with
1 J( e2 Y+ y6 E    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or6 t% U7 s% B7 Y+ @  t
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! [  f' C$ ?: T3 Y3 q1 p  set intersections roads with3 f: d  k% Q  f
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and" V" x+ u' Y8 b
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 H4 m7 ~' w$ Y1 Q* U7 p8 X' m( c
% p) r9 [( D$ Q9 q9 M, b# \% N  ask roads [ set pcolor white ]
1 V0 y8 _: p' p    setup-intersections
7 B0 K1 t4 Z' ~6 ~  A9 Send
/ V, S& a0 n) G) n" v1 B4 H其中定义道路的句子,如下所示,是什么意思啊?% u  d% t; H2 C# e8 \9 H
set roads patches with
, J/ L  g8 U: {' I4 y/ F" {    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; B+ C2 W6 |* P' r$ \* \' @/ o2 R
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 d& p2 |1 Z; y1 J7 G0 |4 x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, 2026-8-26 14:14 , Processed in 0.016504 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