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: 10542|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 B: O: |' f! H
netlogo自带的social science--traffic grid这一例子当中,9 {; ?7 {6 _8 c8 K/ y' a
globals
# o( q- @  H! _$ V# y) O& ?[
7 ^" U( |! z( R' T  grid-x-inc               ;; the amount of patches in between two roads in the x direction$ {) Q6 V# z6 u: B9 R& `3 l& X" X
  grid-y-inc               ;; the amount of patches in between two roads in the y direction: t% R4 H" i' v+ S9 _6 C
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
3 A4 s% K) R$ W' ~+ N6 Y                           ;; it is to accelerate or decelerate- s4 ?$ w, Y6 G; o/ N
  phase                    ;; keeps track of the phase0 A7 f5 e) @4 U  }$ F3 e5 p& u
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
& @. z2 s& _, S' D& [. F& J  current-light            ;; the currently selected light
. l+ U9 }5 j9 q9 f% X8 [; c5 M$ T8 \& M- ?" @  R( j
  ;; patch agentsets2 ~! c8 g; t5 e! p4 g8 g
  intersections ;; agentset containing the patches that are intersections1 f9 T0 X" [& A; `. T! a: A2 L6 O
  roads         ;; agentset containing the patches that are roads% G" u# f5 Q" [( K4 x- e
]
- n9 Q3 Y. o4 d+ l' a: Y$ F! }+ d# w- e, D$ [% z7 m
turtles-own& V6 a: y$ l5 O
[% O/ V/ ?- I6 ^3 S
  speed     ;; the speed of the turtle
6 t' c" X6 ?6 U  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
# E7 e1 ?  [* A6 A  wait-time ;; the amount of time since the last time a turtle has moved
3 q' E- W: `  ~]6 _. o# E) j4 ~/ d' q1 ]
. j7 `: d9 B/ u1 {1 I
patches-own5 w! g! n, \1 c5 c
[
1 @5 w5 E, f/ v) N# L/ S' a# N  intersection?   ;; true if the patch is at the intersection of two roads. A4 @+ j3 @8 e9 K* e$ b
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.0 U3 z, A9 V9 {7 T. |
                  ;; false for a non-intersection patches.
4 P7 K! k2 N) p6 }  my-row          ;; the row of the intersection counting from the upper left corner of the: S  z3 j  C3 u0 r# j: r3 b8 H
                  ;; world.  -1 for non-intersection patches.
. Y# G4 T6 e, \; R9 S  my-column       ;; the column of the intersection counting from the upper left corner of the+ q% ]# _. A8 Z1 a
                  ;; world.  -1 for non-intersection patches.
& Z* P0 ~, _+ q4 B3 ]8 S" c& z  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.) K: X* i+ S. H) ]
  auto?           ;; whether or not this intersection will switch automatically.7 Q+ J( M1 b$ U& ]) [* ^
                  ;; false for non-intersection patches.
- a5 {& n- K- h# \6 t3 Y9 t]
5 V" q, j, Y) ]8 @- W) l  J" i# y, W9 I

2 B( M* S: P5 f;;;;;;;;;;;;;;;;;;;;;;! ]* r) m1 ]- t
;; Setup Procedures ;;' }* @* ]' F! K- `( Y6 \
;;;;;;;;;;;;;;;;;;;;;;# Z, f" N+ ?! X8 u. S# S

3 s+ u  f( B- p+ k+ i7 x;; Initialize the display by giving the global and patch variables initial values.( H8 `# T; ]9 |. u; M& x, b9 Z
;; Create num-cars of turtles if there are enough road patches for one turtle to
, w- r. p0 E- R4 l;; be created per road patch. Set up the plots.
6 h  M6 b' g1 Jto setup
1 G/ m" |- j$ U7 C5 Z9 j' e  X  ca) n; \; K( [, X0 s9 z0 }' ]
  setup-globals2 a1 C; B* X9 E& L3 o' r$ ?

$ k' F# Y2 m; w7 Q  ;; First we ask the patches to draw themselves and set up a few variables9 y5 U. L% ^% N4 t) E
  setup-patches+ X/ Y4 x0 P7 a! }7 }
  make-current one-of intersections
4 w' n" X# N$ q7 L6 M  label-current" i; t" e. \' g2 i+ a% e1 ]' J
6 h* }; q& M" \
  set-default-shape turtles "car"! L( t! i+ L7 [
/ u3 O) T; p; B
  if (num-cars > count roads)7 L% Q& V4 [* o: s4 m: g
  [
' ~/ ]. H# w! _# ?/ T+ T* ^    user-message (word "There are too many cars for the amount of "
, W! z# s/ r; W7 ?, o9 [                       "road.  Either increase the amount of roads "% I* Q; A- {8 N; n2 S0 x: d3 d
                       "by increasing the GRID-SIZE-X or "8 t  z! w$ n( C5 T, G/ a. X1 R
                       "GRID-SIZE-Y sliders, or decrease the ". M1 D( \, ?  S$ x# l) w+ G
                       "number of cars by lowering the NUMBER slider.\n"
* \3 g2 T/ P! W! Q7 G( M, C                       "The setup has stopped.")% J* i$ u1 U4 W7 a' o; g  D6 B
    stop
7 E" j% N6 O2 E$ T  ]+ S; p/ K0 N4 ^' ~

+ b& c( C6 w, j% V/ V  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
& d. O4 S( E3 P; R% H* P  crt num-cars3 O) M" d8 n+ _# ~& m, F
  [
3 ]5 Q& U. u8 y. N6 O; `* X    setup-cars! h- K. f( M# q" e' @0 ^# j
    set-car-color7 V* U( h% K* K- i* i/ x
    record-data
2 f6 @6 F" s! a  ]
, W# ^- [; t. ]% E7 H; f: L
  |1 O& g: ]) [! }0 k( P! ~' f  ;; give the turtles an initial speed7 o+ w8 O% b* y, p
  ask turtles [ set-car-speed ]6 [4 z2 [- N- l) i
& ?) [6 w% X  [$ j7 D
  reset-ticks- h& t. V6 ~8 ], O% C
end
; l' Z+ B+ {8 {+ g0 j8 l3 ~( J9 M; p% o
;; Initialize the global variables to appropriate values
0 P# e6 g6 W* J. O* Ito setup-globals( y- ~" m9 k$ O  n5 O
  set current-light nobody ;; just for now, since there are no lights yet( s* K8 B4 b/ r2 ]& l1 ^
  set phase 0' A8 J3 [9 y8 E( y/ s* i' U
  set num-cars-stopped 0* m, s1 Q1 m4 b5 b4 B) r
  set grid-x-inc world-width / grid-size-x
9 r4 S- z, V8 Z- _$ k  set grid-y-inc world-height / grid-size-y
, i' I) s' i; \+ }! @) q4 K: k; g  ?( h; m
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# _" h2 l, q; E( y5 p  set acceleration 0.099
; I4 e9 W5 U' |% p4 Y, i& aend' D/ Q0 n7 i2 B5 X- R: w/ H, R& u
7 h: U- z8 ~1 F4 [* e. Z
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) X* j. ~+ o1 @0 z/ {* Z
;; and initialize the traffic lights to one setting7 @# z( E5 T, X+ M( w1 `
to setup-patches# \$ g& [8 z: M3 q6 g& o
  ;; initialize the patch-owned variables and color the patches to a base-color( l5 L* k5 u9 j) Y$ q
  ask patches
3 N$ [! ^5 L' q  [0 }. k- |5 P; O9 s
    set intersection? false: e7 a1 A% h: ]( G/ q0 I1 V
    set auto? false
/ r" r+ f/ z! E! A6 r    set green-light-up? true
6 U0 _7 U9 X& u# Q  x    set my-row -12 c  n5 T- e' R
    set my-column -1
- S/ U* y# j* C. u    set my-phase -1
1 @; g0 ]  [6 N2 v, ]6 F4 \    set pcolor brown + 3
) _: x7 \0 ?' l2 G; k  ]
7 Y9 J# E8 a* a- s7 |" M
. D. C5 M% u7 f6 i2 M5 B  ;; initialize the global variables that hold patch agentsets8 B# m/ V0 X1 U9 e+ w& c
  set roads patches with
) s: |& Y1 N& d9 G" K    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- r1 _6 ^* ]1 g  {) }, I
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 P! F9 m$ j* D; O8 h, N  set intersections roads with
3 a" G3 t0 L6 E( ^8 M  [9 X8 n    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" c/ J$ ]- R7 T; m$ W    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& Y1 I+ G) C8 N
0 w+ Q2 H% P  R6 ?% Y
  ask roads [ set pcolor white ]
, s8 ?' q, X. _6 m( [5 o! [    setup-intersections
. N5 G" J- X2 U7 Gend
" P0 {9 p% _4 P$ {0 @! z- q$ k8 ^4 I其中定义道路的句子,如下所示,是什么意思啊?
1 g; h8 h" X) N1 H  q, X set roads patches with
* h! X4 p, v5 _+ o, \    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 @5 W# i$ R) \9 [. g+ [
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. h9 Y- J$ i2 o, ~' w; h1 e# k$ }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, 2026-6-12 12:56 , Processed in 0.013494 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