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: 10588|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 `6 e* Z8 [) D
netlogo自带的social science--traffic grid这一例子当中,/ ~( E3 a8 ~  B& F. {. k
globals( [! \5 O, L. p4 w+ K- S6 _: [
[* `* x+ A! H! k
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
4 }  O. w" p( T" n0 z% k( p+ d) x0 B  grid-y-inc               ;; the amount of patches in between two roads in the y direction
" W- W, A- [& |: T9 ~+ w) m% c  acceleration             ;; the constant that controls how much a car speeds up or slows down by if  T% ^7 s8 g! L. ]0 f3 Z
                           ;; it is to accelerate or decelerate( Y' S3 j2 X' ?5 r
  phase                    ;; keeps track of the phase
6 a9 i8 Q* a1 N4 A0 p* g  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure2 }  N4 K: G6 s( d
  current-light            ;; the currently selected light
' ^7 r# u2 @: r  }; g
) ]7 Q) {, q+ s% M2 z$ W  H- N* V  ;; patch agentsets
. U' q/ j0 A" R' d  intersections ;; agentset containing the patches that are intersections
6 e+ j2 D3 t" y: e0 b  roads         ;; agentset containing the patches that are roads6 _/ Q# ?5 V+ E4 q* t
]
3 X+ v5 l- {9 x! U
0 ]& Z, |  A5 O) c0 J+ g& n# ?turtles-own
, F( J% A( R& G% ~[: x8 H5 s: o  O$ J# H
  speed     ;; the speed of the turtle
( ~+ C( w/ N7 z# a9 E/ X  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
: g) w/ o# r. s- Q  wait-time ;; the amount of time since the last time a turtle has moved
! ]  |' Z/ O" []
* E& i+ k1 V2 x" r9 ]# y, c  p( d
/ O' b/ l. F  p0 a" j( ^patches-own
" p+ c- X, z9 B" h[# W2 t! h) k/ u3 k9 M. T8 w7 v
  intersection?   ;; true if the patch is at the intersection of two roads
. Q* [0 G( N5 c& U0 F  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
- c% w& G; `% ?  y- u1 P2 O                  ;; false for a non-intersection patches.
" }4 k* Z! m1 j9 f% C  my-row          ;; the row of the intersection counting from the upper left corner of the8 S" }% k) J4 W
                  ;; world.  -1 for non-intersection patches.
! b- t) N# U* i  my-column       ;; the column of the intersection counting from the upper left corner of the
6 m0 E. j% c) P                  ;; world.  -1 for non-intersection patches.  B% p  a2 X/ ^, ]2 Y5 m4 P) i
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
% [! ?, `6 h% y& r: Q3 Z# b0 C: i  auto?           ;; whether or not this intersection will switch automatically.4 Y  v$ F  q: K
                  ;; false for non-intersection patches.( O& e, v, x$ ?8 L! x
]
% Y, J1 @. _* z8 p( D% ~9 V" l8 u( }3 ?8 H; j

* l( t$ @: @& r  H7 n; t/ P;;;;;;;;;;;;;;;;;;;;;;
7 j, C* z3 s7 o, w  z;; Setup Procedures ;;+ Q1 h0 _; H; h+ t& x: \# [1 B$ _0 |9 P
;;;;;;;;;;;;;;;;;;;;;;
3 Y7 H7 r2 J: P6 m8 y$ ^
3 |0 X+ j9 ]% D$ h# d9 z1 f+ O;; Initialize the display by giving the global and patch variables initial values.
9 K  p7 u7 m9 T;; Create num-cars of turtles if there are enough road patches for one turtle to  N, T/ S5 y: y2 d4 [9 O/ o
;; be created per road patch. Set up the plots.: ?' r9 Z8 {( [7 ], L
to setup* v6 h9 [, V9 ]6 j; X
  ca6 ^! Q/ g5 `; _7 `# Z% \( l& n" u
  setup-globals
6 k8 }: L6 W% l7 {! ?+ ^5 }  t" f4 g
  ;; First we ask the patches to draw themselves and set up a few variables
, d& r6 N" F2 k$ F  setup-patches
. X: M7 R: h$ J2 U, G  make-current one-of intersections# F+ J5 G! T+ e/ P+ p" j; T
  label-current& O; F5 `% `% H# p" Q

, ?& W0 E/ H4 F+ ?2 s  set-default-shape turtles "car"7 C) O# Z) `+ R  J
) E" O  W' ~4 j+ U( @: U& @( T
  if (num-cars > count roads)
* @7 `! m# T) R$ ?+ A1 F: D3 M  [
7 I$ E! q6 r# M, U5 |1 r% D$ W    user-message (word "There are too many cars for the amount of "
4 ^2 P- I0 c3 \                       "road.  Either increase the amount of roads "
3 b2 ~+ b" c2 c4 U' W+ D                       "by increasing the GRID-SIZE-X or "
" N6 o6 T9 u, E" L2 |7 `1 y# i                       "GRID-SIZE-Y sliders, or decrease the "4 z; f* F5 h! _0 d( q( i+ w0 p
                       "number of cars by lowering the NUMBER slider.\n"$ H( {' W, Y4 V, O/ F
                       "The setup has stopped.")  q" G, Y& O- S2 _2 B% i; V
    stop. b: j4 P8 g* F! E# d
  ]2 U7 ^* }+ I- L: I

4 U0 N7 W' y) F. O6 E& c1 T  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
# Y: f$ o+ P' z* u  crt num-cars, _7 Q% V7 u! C9 _; q% s
  [
- D% a; i2 {/ m" [4 k' P    setup-cars  d* Z3 ]% M1 m# m
    set-car-color
0 S' V; s( T9 [: Q9 `9 h- t    record-data' ]. s) W  R- y' M/ Q0 S
  ]
& b' p* y4 X4 x6 }4 O& V. f' U  }
" \' B' y8 ~* q+ L2 G  ;; give the turtles an initial speed
- E8 H$ P8 k: I  ask turtles [ set-car-speed ]( O: h( c; I0 V% g! }5 U4 z5 W
$ L3 n" h& f! H4 l! [! U
  reset-ticks
, I3 }/ E+ H, M, q) kend
7 N6 S3 Q# s( y2 V# a" G
( i$ ]3 j7 }* H: |! H;; Initialize the global variables to appropriate values6 H4 z! [3 E& [
to setup-globals
' K- C' D* n7 |0 X/ F' g4 u! g  set current-light nobody ;; just for now, since there are no lights yet
& c2 E5 K4 K0 z6 _' O  set phase 0
( y) a' ~2 u& i; e: r6 q  set num-cars-stopped 0
% A- k1 n+ D; O3 {% ~; C  set grid-x-inc world-width / grid-size-x9 `* y& P8 H% F$ J/ e& O1 P/ H
  set grid-y-inc world-height / grid-size-y# e1 H' W! C7 S) C; O6 J8 a

8 M2 R- A) Q$ w* O2 V  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
! G* k! w5 ^: \5 a: T  set acceleration 0.099
" X  C/ U& }; }end
/ K) O3 q, {8 m% j& s9 w/ y8 L2 S4 {2 D% O/ R% ]4 ^
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
$ x/ z# U, z# J;; and initialize the traffic lights to one setting# J) Y& E7 n, h3 x
to setup-patches2 b6 A% }3 B8 u% h8 i/ ]' E3 ]9 X: m* Q
  ;; initialize the patch-owned variables and color the patches to a base-color: I. y1 w: J+ I# c: z
  ask patches
) o- c/ f& Q: h  u- ?  [- s/ G& l; V# l5 C1 M+ t
    set intersection? false
; K* |. u/ e( M: ^    set auto? false
5 X" _" v+ C1 o7 M    set green-light-up? true& a. M% h, N4 J# f# K* ~
    set my-row -1
! l% p3 ]( q( _5 \) d  n7 r    set my-column -1/ d' D9 M+ w+ q: L; ]
    set my-phase -13 M1 R8 ~9 L0 R. d! y7 J
    set pcolor brown + 3
! j1 H. x# V' l$ e  ]6 ?' P: D4 b% K0 P6 N

" W, E- `4 G  f; z+ N1 W: g5 K# i1 J  ;; initialize the global variables that hold patch agentsets4 D0 U9 }$ U. ^) o. |% N
  set roads patches with
% O: ^, Z) W, ]; P5 }4 W    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ H8 H" I$ m- D6 m5 J: f9 M% ]    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 Z" ^& i* ~$ T8 E, v* O- w5 j; o6 W
  set intersections roads with% j5 s8 p' ^7 [; B
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
: d  i4 K" A5 b    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
  B, ~# {. F. z9 q5 u$ ~
' u( A. Q( U" o7 |5 C  ask roads [ set pcolor white ]3 D" z6 S6 R/ X1 `! g% V% ~
    setup-intersections
6 ^+ l1 S" Y: a$ d. `7 c9 Tend
( ]; }" |6 S, k  u, D% k其中定义道路的句子,如下所示,是什么意思啊?
; j) Z/ K" B3 z6 \8 ? set roads patches with) X3 U1 p% T! i! {7 ]8 [
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ d1 {  a  l2 `; P- R
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( k) x' a! u* X0 I# U. Q
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, 2026-6-15 09:47 , Processed in 0.013421 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