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: 12208|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。2 `' V' c, A; t5 _8 t* B- _
netlogo自带的social science--traffic grid这一例子当中,. ~, K: L* C" w% e1 f
globals4 i1 N) T! j' P
[# D: f  A/ ]- P
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
+ g3 ?" i. R+ B; c- i5 W' M2 _  grid-y-inc               ;; the amount of patches in between two roads in the y direction3 U( O: [9 R( ^1 A) S6 d- d9 k1 T* d
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if8 {; U, b: z( s6 q& s+ N, d  O
                           ;; it is to accelerate or decelerate
" P4 ^0 p" N! L" y0 \. p- Q5 P  phase                    ;; keeps track of the phase
6 ]' g+ m9 V2 z6 C/ b! `: R  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure3 n! j# D3 y# U4 X" x. e
  current-light            ;; the currently selected light# V- ?7 c# A, ?* E

# S$ P3 d( i5 I& S8 z# q  ;; patch agentsets5 |( c& [3 {9 i) W6 A. \  e
  intersections ;; agentset containing the patches that are intersections2 P7 Q% E8 V7 ^! x- |  _5 _. ?0 F
  roads         ;; agentset containing the patches that are roads+ W- z' n7 l0 }' i6 Z# x8 B+ s
]+ y5 M! Y3 t* \. G7 }
# _6 |1 u/ `+ O
turtles-own
# t1 s, q! s9 l; I. `, f2 f0 v* Q[
" M; i, x; C# {9 z" {7 L$ m  speed     ;; the speed of the turtle
+ J% H- M* E4 J: L3 ^& f: _  up-car?   ;; true if the turtle moves downwards and false if it moves to the right5 f7 {; C9 n6 G. f
  wait-time ;; the amount of time since the last time a turtle has moved
! M7 e8 G6 u, x1 A0 }1 `]9 v% J7 E+ w4 h* I0 ~7 @+ s

4 R1 s: Q0 W* O& F- ?patches-own" D' k0 Y# b0 i3 i
[
# \$ W2 u) {* R0 X" K  intersection?   ;; true if the patch is at the intersection of two roads0 X& J: g% |' @  |5 @# S
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.0 \3 S2 W7 d, D  i
                  ;; false for a non-intersection patches.  N! H6 U; h  _( L
  my-row          ;; the row of the intersection counting from the upper left corner of the$ B3 [: Q9 e) g1 Q' s
                  ;; world.  -1 for non-intersection patches.5 i$ k1 @- |+ d
  my-column       ;; the column of the intersection counting from the upper left corner of the
3 x5 G- _% Y' N9 F! O4 U                  ;; world.  -1 for non-intersection patches.
/ u7 ^; {" y8 J% n  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
5 V! r1 N+ B+ ~( m1 I* q* f  auto?           ;; whether or not this intersection will switch automatically.
* _% V% d; X) N: Y$ J                  ;; false for non-intersection patches.0 j$ @  V/ v! S2 q8 `  t
]+ I" A4 H# ^. _8 |/ q5 F
% m% m& d1 i( W* L, N

2 M, o! h, }* M' x( B; K) W3 c' J;;;;;;;;;;;;;;;;;;;;;;
6 ~) Q9 F" M  l( H# O$ Y% C;; Setup Procedures ;;
8 ~8 E6 n9 U+ x* R;;;;;;;;;;;;;;;;;;;;;;' D1 L7 N: a/ `. ?/ ?) l% H
0 E& d6 b. k0 ^* \- {9 l
;; Initialize the display by giving the global and patch variables initial values.
! w- O6 g' ^( @' W6 W! Z;; Create num-cars of turtles if there are enough road patches for one turtle to2 Q2 F6 H5 M8 l% x, F8 G
;; be created per road patch. Set up the plots.
4 Q2 A! `: c: S9 {to setup
6 y2 G2 {6 [) K6 F5 Y4 d, m. U  ca$ P$ G* {6 N$ b/ a3 p
  setup-globals/ h6 |2 @6 D9 T, R+ j. r
1 _% a: M2 ~+ y$ V9 X  N3 G
  ;; First we ask the patches to draw themselves and set up a few variables
" t, M6 u! t9 ?% J  setup-patches
: }+ Y$ l/ @% p4 \1 D  _( ^: x  make-current one-of intersections
; h2 T. T& H* v# Y) \* D, b" |  label-current
# r! A: g9 E$ t2 g/ h, x' k& b# n
- `8 U1 q! ]9 I# c" l: I  set-default-shape turtles "car"& b0 U0 G, B/ Z/ m

$ F& @8 p- U* T" s! [/ s9 |  R+ y& @  if (num-cars > count roads)
8 f5 U4 @: ^; L. b2 g5 S- A+ ~5 F  [
- c! d. O7 k* s1 ?6 w& |; K    user-message (word "There are too many cars for the amount of "
# v3 A2 e( s, ?0 n                       "road.  Either increase the amount of roads "
7 a- T; e0 n" @+ N6 b% `                       "by increasing the GRID-SIZE-X or "9 [8 T3 i+ d! l! m" p1 i: g
                       "GRID-SIZE-Y sliders, or decrease the "
4 c  P& S2 }! l" i) q                       "number of cars by lowering the NUMBER slider.\n"& W! @4 l, Z/ P1 g/ K. C
                       "The setup has stopped.")4 ^2 d5 y  U( _. Z8 x
    stop3 w2 }: V5 ~1 Z
  ]( \) X- @  u# {6 U# |9 }/ F

! X6 H. T( o# w  T3 T# h  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
& R# Z2 H; T& G  crt num-cars3 C" U4 J; _+ s' q- |
  [8 b& l6 b! L7 E7 U# B
    setup-cars
. N3 `8 N6 F% J" v4 K$ ?    set-car-color, ~9 }" X9 Y: X: F: f8 i# T
    record-data3 @" q2 a$ i( b% Y$ n
  ]
. h# E7 a6 x2 P5 E4 _
1 Y, T# U' w4 v2 y( Y3 r  ;; give the turtles an initial speed8 m# ]' R) T- e& P( V) i* j# V
  ask turtles [ set-car-speed ]
8 [3 j; X  J; K( k+ P/ j
7 Y1 N9 a+ k& r+ ?  V7 Z; I1 q/ l- O  reset-ticks' Q: V: m; N3 b5 @
end
# g# m  N; y) W+ p% h$ w; `( c8 g; W' n+ f
;; Initialize the global variables to appropriate values
! O9 m7 }& t4 |: b9 a3 `& C# cto setup-globals
  c0 f4 L! z) l3 v5 B  set current-light nobody ;; just for now, since there are no lights yet
8 o$ p' P& Z* m+ w  set phase 0
& A; L0 y, z8 `  set num-cars-stopped 0' N  m1 h& p& {; j1 |0 }
  set grid-x-inc world-width / grid-size-x- F9 v6 A9 u2 `. v9 |0 z
  set grid-y-inc world-height / grid-size-y6 n5 x! z. Q9 E8 p; Q+ b
& u# x% j1 U5 D0 o' l1 c; X
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
% ?  ^1 q) d0 a6 I  set acceleration 0.099
6 E0 x' _1 y- V- s! l& hend7 ]% N( P7 c; e; p5 X

/ i1 a0 ?. d' Q/ s;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
+ U/ t7 M/ W& j7 B4 Q;; and initialize the traffic lights to one setting+ T. B; C# w: b+ E  _+ |7 {
to setup-patches( f( I* [; L; k1 j  G7 j" r
  ;; initialize the patch-owned variables and color the patches to a base-color
  ~( M  m6 O% ~  l4 W; \  ask patches3 V! y) _7 a5 y* f% H2 @5 J
  [+ f& s4 r8 N( I/ _/ _; L
    set intersection? false8 G. ^9 `3 \  X# Y4 ]$ b8 W
    set auto? false
' |3 @1 d6 |- p$ R( v    set green-light-up? true) l8 p- C# W% Q
    set my-row -1
5 r/ ?, ~# j) Z! ?% i4 n4 g& B+ O    set my-column -1. s0 n: A9 B0 ^4 Z4 p
    set my-phase -1. ]2 t5 K6 |7 x% G0 D
    set pcolor brown + 38 C# ^- r" G* e' v" I! o
  ]
, @, W6 Q1 O1 q4 q, _  P: q2 @- D7 q% Y( }6 \, P" }
  ;; initialize the global variables that hold patch agentsets1 y2 l  U9 G/ ~: X
  set roads patches with: L4 {: b% U9 r8 e2 F
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' ^$ S+ |$ \1 s0 m) h
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 ]8 f1 e& a4 A8 J) B+ b* Q  set intersections roads with
4 B5 O1 v6 Y' J    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
) x: r( ^. J* D1 l1 v: @9 h    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) }0 z# J  p& p) U' G2 h) u+ h
; A' v: |" S' d% Y( i% |9 ?- J  ask roads [ set pcolor white ]  K" t8 ?1 J1 O5 E1 \
    setup-intersections
& D* E1 s( z5 Y% s& zend/ k+ Z7 e$ Q" R4 ^
其中定义道路的句子,如下所示,是什么意思啊?8 ]$ M5 G5 }0 G; i3 H2 _
set roads patches with7 V( g  I. N& z: I3 }6 H
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" r9 l# O0 _" ]1 g9 C    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 m: n- A; j6 J$ o
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, 2026-9-9 11:43 , Processed in 0.017558 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