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: 7707|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。
8 c9 N9 ]& P; n! Z* cnetlogo自带的social science--traffic grid这一例子当中,+ `( J9 H1 ~- Y# H+ y) ?/ n9 |- a
globals
+ Z) v1 Z: L0 ?) ~7 N7 g. T[* `5 T+ m# ]- v; U$ Q
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
9 }& @# [! S8 L: i9 {  grid-y-inc               ;; the amount of patches in between two roads in the y direction
5 o( i4 V. d/ p  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
8 [- {9 K/ E; E1 ]                           ;; it is to accelerate or decelerate5 Y0 ~6 |* }. |! y# P! P) Q
  phase                    ;; keeps track of the phase# A6 b1 [' @" d* O% x' G9 U) n8 }
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure9 k5 w9 S" x& v
  current-light            ;; the currently selected light
: c* U2 `2 u6 `6 T8 }/ D
; K  x3 l5 ]7 ]1 H7 q1 m" v4 V) F) |  ;; patch agentsets4 a: z+ L0 x( @- A2 A
  intersections ;; agentset containing the patches that are intersections
' @1 L4 I) U; Z# f8 P  roads         ;; agentset containing the patches that are roads
/ b: ~3 ?2 c0 w, j" o]0 U# s; {4 E5 h* ]2 f
. X; ?$ y/ k4 Y: @2 ^' N6 `
turtles-own
# Y- e% d" w% P3 v  y5 w, _[! s- H5 ]3 n+ o
  speed     ;; the speed of the turtle4 o- g/ Q, {, u& S- P
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
- y! `# O- q: z. `1 x4 q  wait-time ;; the amount of time since the last time a turtle has moved
! f1 A) E/ F( S+ l9 e' P]  Q4 D0 W) J. ]) L  T

. ^: {1 N# ^6 M1 G: epatches-own+ }/ Y8 k' s& O5 Q2 W0 j3 |* o
[
1 A' ~  \. O+ z/ t8 k) {4 x$ ]  intersection?   ;; true if the patch is at the intersection of two roads
4 S; H4 j" N  y) p( f! m  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.0 [; ^/ j1 [' P( k$ R0 l6 K- G' M  s/ k
                  ;; false for a non-intersection patches.( d' C5 j, ]; C
  my-row          ;; the row of the intersection counting from the upper left corner of the
$ M, H" i* s0 s- ^. M, ~8 `+ W: I                  ;; world.  -1 for non-intersection patches.
# N- l( e! ?( p9 y  my-column       ;; the column of the intersection counting from the upper left corner of the
& p! x% j/ P' Y                  ;; world.  -1 for non-intersection patches.
4 J1 p: \" s3 z0 F. _  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
) C9 a0 o9 y& Y" f7 x  auto?           ;; whether or not this intersection will switch automatically.
+ S" U9 J! Z7 p( c8 k4 i                  ;; false for non-intersection patches.( F! s, r9 I. U
]
0 [0 m2 B+ O$ ~$ a& H
7 G& V' b2 C- j& e. _' g1 s2 s$ p# Y
;;;;;;;;;;;;;;;;;;;;;;
% r4 o+ }9 q( _. \& K* R9 `, B;; Setup Procedures ;;
% _5 i0 p/ c3 i2 c9 N2 s;;;;;;;;;;;;;;;;;;;;;;
* p: k: [2 w( @- l; x% \0 ]" X8 H3 {) ?& J
;; Initialize the display by giving the global and patch variables initial values.0 x, j! c0 s" y3 W* c9 b" b
;; Create num-cars of turtles if there are enough road patches for one turtle to
1 Z1 @2 i3 H1 h3 m2 B8 `, g3 B;; be created per road patch. Set up the plots.9 j' a% t- O. y% d
to setup3 w" H  _+ C; l( r+ w  E/ S+ R' B
  ca
! u9 o. }/ [3 Y' u3 J# N: G  setup-globals
; K# o: K- V2 s; b. t' }/ c9 n( u! a  A: s8 N, ~
  ;; First we ask the patches to draw themselves and set up a few variables" }2 [. K4 C: S
  setup-patches
. f* V' v. f3 j: ]  make-current one-of intersections$ U7 ?: h: ^! J! U: i0 _
  label-current( }6 V, S+ P: q/ T$ A- ^" M

# l+ ]5 b  u7 l9 Z' e9 j: {  set-default-shape turtles "car") l/ A: P  p3 E+ z4 w% @

' i( W& H! m9 R4 y  if (num-cars > count roads)4 ^0 {! P% o3 E8 t  }6 H
  [2 Y6 b. b4 _5 }" D3 d8 h5 ]& U
    user-message (word "There are too many cars for the amount of "; r0 F" q; B9 J" A( @+ e: G
                       "road.  Either increase the amount of roads "
8 R$ N# X; j6 Y! d                       "by increasing the GRID-SIZE-X or "
# D0 v9 n  x! e0 X1 l& g                       "GRID-SIZE-Y sliders, or decrease the "
, Z. O' r: |- G: ~( O                       "number of cars by lowering the NUMBER slider.\n"# A# O" N+ k+ i( D. `4 g6 ~
                       "The setup has stopped.")
. Q+ A! w: b4 G' A    stop8 x7 C4 W# j- n5 e! U" R2 j
  ]
$ S9 X) m2 C7 r: H" w1 B  N% H) H
: m+ {8 O/ a2 p2 ^' B. H; M( y  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color7 L+ W& V6 ^6 H
  crt num-cars
" i& L7 Q, b9 Z3 w  [
" H6 X) W- B- Y6 _5 H9 ]) B+ _+ L    setup-cars7 {# q3 P: r9 j9 e. u; i
    set-car-color
0 c$ b- ]% ]# W/ b    record-data
6 i+ w& j( y0 a  ]
  K$ g. Y; L. V- _
, ?( q0 C8 `' [' U) K6 b  ;; give the turtles an initial speed
3 \2 e& N" E3 O9 f* [2 Z# s2 x0 k  ask turtles [ set-car-speed ]& _$ d7 X0 P" p" E

" C: @& c( T* Q1 o  reset-ticks
3 a. m# b/ U+ `0 Y2 Fend1 J) T  x2 U) S( W5 h

: q! U% b9 I1 e9 F) b;; Initialize the global variables to appropriate values
# e& V4 x# ~; T* H+ l  p$ w. |to setup-globals
8 f/ K7 ]; D! s. c  set current-light nobody ;; just for now, since there are no lights yet
" M5 s% _/ x9 r: L2 i  set phase 0
7 R1 G( W$ l8 l/ w0 h6 d2 Q  set num-cars-stopped 0
9 V+ ]" |0 T& H/ r9 p* n, E8 Q1 E  set grid-x-inc world-width / grid-size-x! O$ y6 z3 j  L
  set grid-y-inc world-height / grid-size-y1 o* C& u0 C; O& O& y- u
' R# ]+ P8 T) R' w
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
' y  t0 e9 A- B( l  set acceleration 0.099: i! @: T2 t; u9 q' {: f
end
+ \) h6 q% i6 K: ?& V6 h' X. R# s- f$ x7 U  p
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,! u: W1 {1 X3 o* C0 _8 a
;; and initialize the traffic lights to one setting0 _- U1 M% z9 Z+ j% G$ N& d
to setup-patches) j. ?: u1 l% m' l7 K: H
  ;; initialize the patch-owned variables and color the patches to a base-color/ c0 L9 v4 [3 L, L' Z
  ask patches
8 S( }3 u5 ~. u' B+ a1 Q  G  [! [+ \3 i- ~8 g! t8 F1 n% d
    set intersection? false1 V2 U9 m) H2 Z! o* x9 }
    set auto? false9 j( B, d- r/ A* d! E
    set green-light-up? true
. @! I4 v# \; z6 Y; ]    set my-row -1* W# [2 v3 t/ D, z! Z
    set my-column -10 f& u9 w/ {9 x7 E7 `: @# ?
    set my-phase -1
3 z5 |: l  d  z$ P% n- i, T    set pcolor brown + 3
2 C8 Y$ ?# B) X6 j1 w5 E7 @/ ?  ]
- s* r1 E% ^' O! [# l  V
7 b* \) l( u( T3 w' u- w  ;; initialize the global variables that hold patch agentsets
, R, ?- M$ \7 R! i1 D- o* {& y  set roads patches with+ c8 r/ H$ Q$ {% c8 B# P# ]
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. @# N' x0 P2 }! ?    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; s0 X8 a3 z. k& e. \! [* @
  set intersections roads with
7 v' s/ ]8 I+ X: F( @7 O    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
- U9 Y4 ]' X- Z: v# s$ e    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]  D8 d' U7 U8 T3 v) P" Y" x2 u

, L+ V+ {  \( @# m6 a. w; @  ask roads [ set pcolor white ]9 V0 S" Q3 f# b
    setup-intersections. Z! E% r7 `8 M; F
end
+ j+ K8 \: B4 ]% b, N$ w其中定义道路的句子,如下所示,是什么意思啊?7 J# a4 n2 x/ S: E9 Q' Z* a
set roads patches with
5 e) a( R5 t3 G7 G5 x    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& N- M( n/ n/ d6 K# A! n
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 u1 U" O& F$ b: k. V* V& N
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, 2026-1-9 10:36 , Processed in 0.025949 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