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: 8209|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。+ A- R; n; y6 v
netlogo自带的social science--traffic grid这一例子当中,9 l: m& X& p5 R2 P" Q( H
globals1 H) V3 W2 B- Y6 p  @+ ^
[  D* ~. k) `# `4 t1 K
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
% l7 u; I( }7 ^. r5 Q. h$ y+ G- V  grid-y-inc               ;; the amount of patches in between two roads in the y direction
# v% Q$ I4 Z- O" ^  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
4 J9 _0 ?3 _) P                           ;; it is to accelerate or decelerate
% K( O, i/ w+ a2 L- L  L) z; d  phase                    ;; keeps track of the phase% h( T* M' Q9 R3 i
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure4 |+ N' u5 y2 h. v) c' ~
  current-light            ;; the currently selected light
3 m- j" o7 P# ?3 M* d& i
4 _- U6 n. m- a  ;; patch agentsets
6 G- z5 R% r2 Z  intersections ;; agentset containing the patches that are intersections1 e$ Y1 Y6 R  |3 m5 r
  roads         ;; agentset containing the patches that are roads8 t0 G8 b3 B: z1 x% G7 Z; U& R
]1 x: R' y  \. E4 e; G

& ]; J. t9 U/ d' c! dturtles-own: g" N7 ?# Y& x* r! |
[' l" v$ s, V' R( i$ t- A) w
  speed     ;; the speed of the turtle0 Z1 s( f! \3 V' j- B
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
' x8 c- |0 }- e1 h  wait-time ;; the amount of time since the last time a turtle has moved9 E3 F  _+ C  T" q( ?4 J. Y+ j) ]
]# `1 O# g9 p, \( P: X, c
. g  K# c- @$ B' [
patches-own
- ], r' V) S2 e7 E) i[
9 F0 I7 `* O0 X  intersection?   ;; true if the patch is at the intersection of two roads  x$ K# x" k/ _9 T4 S
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
1 E# U8 m. K+ d" Z) w  e# h1 Z                  ;; false for a non-intersection patches.- o& }& ^8 g3 ~9 \9 M
  my-row          ;; the row of the intersection counting from the upper left corner of the/ q, {8 e- T. t
                  ;; world.  -1 for non-intersection patches.: j6 P8 H2 e/ j1 U$ t, i4 Q
  my-column       ;; the column of the intersection counting from the upper left corner of the: _- }2 V6 k0 v5 e  l
                  ;; world.  -1 for non-intersection patches.8 |- e5 J) [0 `# [# a
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.9 {6 m$ I! S' I, W) |1 g
  auto?           ;; whether or not this intersection will switch automatically.4 ^4 @; C8 n; H6 m6 u
                  ;; false for non-intersection patches.9 F/ j2 u' h5 y5 }- Y; J
]/ u" g* Z1 ?- W1 G
& L9 u6 C0 c' e4 r% n
: \/ L9 w. l9 U6 t* B+ l, w6 E; `, ~
;;;;;;;;;;;;;;;;;;;;;;
8 \! K0 A" u! m$ t, _;; Setup Procedures ;;
( Y8 I' m1 t9 `;;;;;;;;;;;;;;;;;;;;;;% L( y; u3 O4 }# |. j; N3 w9 m
! y7 _& c. g4 M% Z) ~
;; Initialize the display by giving the global and patch variables initial values.4 B' _- Q5 K, D$ O; S: h
;; Create num-cars of turtles if there are enough road patches for one turtle to
& {9 n3 g. z9 q/ C+ m  W;; be created per road patch. Set up the plots.
1 W7 m& O* Q% P# Y0 T' eto setup4 n) `/ |7 E& a/ K5 _- e; p
  ca
# w2 L# k, N6 A3 X" {" y& B6 G  setup-globals, C! x9 j+ X( `$ U
. p! Q& o6 G' \( m
  ;; First we ask the patches to draw themselves and set up a few variables* N/ s6 t* G) F( d& d3 O
  setup-patches
4 u. H$ Z# Q% H  a  ]4 ~  make-current one-of intersections
' p  i4 h( A6 z. t# S  I  label-current8 I! v) P; }; u4 ]3 K, ^5 _
4 u% y- L! Z  B8 K
  set-default-shape turtles "car"
3 @" N, a3 _: l$ V5 U/ d
8 a. i3 O) m' Z. D' W1 v  if (num-cars > count roads)% H8 j) I7 `& P5 d: c( \( ?
  [
0 k  H# q- [0 L/ L6 ]) x4 Z    user-message (word "There are too many cars for the amount of "' X6 ?5 N, ]. J0 G9 `
                       "road.  Either increase the amount of roads "
3 J6 G! X% ?4 o" w0 S7 `, z                       "by increasing the GRID-SIZE-X or "
( N3 w) s- e8 T- @) G                       "GRID-SIZE-Y sliders, or decrease the "
: i2 b+ q; Q5 k) h7 o) n; c1 y% u* _                       "number of cars by lowering the NUMBER slider.\n"
8 J$ Q# i- o) [; k& S5 e                       "The setup has stopped.")( w4 Z2 P4 B6 G* e; P; x2 h7 T/ g
    stop
( d2 l. u  Y5 k  c5 P. ^  ]7 Z# B, }8 b5 i" `0 A

8 D! T' I( x2 e  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 b/ l& K! n4 `+ a% i: E  crt num-cars
' x# q% t3 t, i& M. N4 x  [4 |7 d/ o3 ?' c% H: h
    setup-cars5 g+ g2 S6 [9 |. N( y
    set-car-color' x* r' z2 w$ }; b8 o
    record-data
6 ~4 K0 d! @: o0 H  ]
& x( f5 e: ]* ]6 Q) Q5 Y$ x
) ]0 ~! N5 l" k4 [8 @  c) L  ;; give the turtles an initial speed
$ z) T/ _" |8 ^5 i  ask turtles [ set-car-speed ]
" v  T: U& v0 ?  u' b8 r8 D
  E: i+ S8 ^! M3 d% F; x  reset-ticks
1 r" V7 f8 D% G! pend2 a5 ?" W2 q% S( l9 D
4 o( S$ }9 z% j; D
;; Initialize the global variables to appropriate values
3 n: t! ~/ ], W; Lto setup-globals
8 @  \- r+ r6 _3 D7 m  set current-light nobody ;; just for now, since there are no lights yet
0 p1 b3 B8 \6 n4 v5 z- D  set phase 03 c* m3 B4 V: ^, W
  set num-cars-stopped 0% Z$ @- b& V& l6 v, k7 q
  set grid-x-inc world-width / grid-size-x# A. X8 e# }& p0 M
  set grid-y-inc world-height / grid-size-y
& Z1 Q7 C- f8 i3 z
) f/ O4 G" \; `1 T/ T  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
; \/ t3 C; b! G! O# `; N5 L  set acceleration 0.099
) v5 |. m0 p2 }/ p$ X. U2 X6 lend- B" Z* S& V( \7 y4 G

' |- u( z" U: m8 m* P$ u;; Make the patches have appropriate colors, set up the roads and intersections agentsets,3 C( s8 e" U# [
;; and initialize the traffic lights to one setting
  u5 B* V  F' E5 L' j. Wto setup-patches/ X7 E8 Z* L+ e
  ;; initialize the patch-owned variables and color the patches to a base-color
7 H& i9 a1 B  {  ask patches6 Y. h+ J3 |1 k/ C
  [
  k* ?3 K3 q7 \; ^- n' U    set intersection? false
* O7 i* k- Q* X* m9 c    set auto? false
* F( y" e# T# _/ V% x; n8 p    set green-light-up? true1 D" w9 z8 r1 g3 B' M' @7 L
    set my-row -1) Q2 r7 \$ M! a8 o) T
    set my-column -1
4 z0 J- s5 K! R2 w    set my-phase -1
) ?$ Q- Y9 y4 G& k' W6 e4 p    set pcolor brown + 3
7 F8 o6 D$ M# F. o) [  ]
* c; c% A, m, j+ N2 F
8 T& r  w/ J+ i* j" ?4 k  ;; initialize the global variables that hold patch agentsets
/ F0 ]; t, f3 O  set roads patches with
' i4 ^  |0 x- Y6 [5 p    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# y) m9 L  |7 B8 D    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]  {; B% W% }* P' R
  set intersections roads with" ~) K8 F- u. e. M* f( t6 K$ v
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and5 Q. H# i- z2 y( S! Y) N( z
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 a+ O/ @& ~% Q) b& B. _9 Q& G! j5 v. r) H
  ask roads [ set pcolor white ]
( v( p, h2 E& Q9 w- {8 F4 H* Z+ P    setup-intersections4 g$ i6 j$ I: U% V2 V2 y9 Z
end
0 V1 v2 g! K, g4 \" g其中定义道路的句子,如下所示,是什么意思啊?: I4 \5 F( s+ G6 C: Y5 g# p+ \
set roads patches with
  p/ z' h0 o" o5 `' b- Y    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ z! n: P3 \$ l. s# u    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& z# u2 A' P5 u) d* e4 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, 2026-2-6 19:47 , Processed in 0.020146 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