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: 10169|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。
* q# U6 [3 O! enetlogo自带的social science--traffic grid这一例子当中,* t9 D2 f: D$ L9 n" V4 x
globals* S6 G4 ~0 L/ T# I
[
& i' M! c/ o8 W: z+ B1 w" B  grid-x-inc               ;; the amount of patches in between two roads in the x direction
0 R/ d, M2 @1 X# k5 }  grid-y-inc               ;; the amount of patches in between two roads in the y direction
9 L0 Z" [$ D7 v, K1 G% G  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
) I2 ]* m7 p* d( S                           ;; it is to accelerate or decelerate
5 \& M( p' U8 V: I# u' q  phase                    ;; keeps track of the phase- X7 w' K7 J; g1 u/ ?0 c
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
1 _! O8 d  R+ R* o1 c  current-light            ;; the currently selected light
1 z9 C) a$ F6 v3 R3 a# S; n: [- t4 ^! g5 Y# L/ s3 I% c$ e
  ;; patch agentsets, r# ?/ P* v& l( f" ]
  intersections ;; agentset containing the patches that are intersections# \+ m- j6 A7 y9 f  F
  roads         ;; agentset containing the patches that are roads6 v. c: b) D, n) z) M7 x
]
# t: N' f/ ]+ E& r8 s, G- y3 @' j. E1 _& @& U
turtles-own
6 I' @3 @* N  o1 J0 c  t  k& x[
8 [* ^$ I* ^* Y0 _0 G  speed     ;; the speed of the turtle6 b- H  y  F5 E
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right2 T/ J- C- ?% I3 Y, V. I6 `8 z* s2 f# {
  wait-time ;; the amount of time since the last time a turtle has moved
5 n' v$ t8 W9 d]" k3 Q* i: _3 X. b

: v) w# P( r  h. Ppatches-own( M9 S! Y4 O7 r* U1 {
[; r3 N! h3 Q% @" C4 c  }
  intersection?   ;; true if the patch is at the intersection of two roads9 ]3 N2 b' x5 h# O$ ]6 X
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.5 M) D# r$ ]0 w% r" o0 B# j
                  ;; false for a non-intersection patches.8 ?/ e. ~$ c6 _& l5 g# G; R
  my-row          ;; the row of the intersection counting from the upper left corner of the: h2 U- q  r6 i# }
                  ;; world.  -1 for non-intersection patches.
1 ^* C& O4 ~. |# |  my-column       ;; the column of the intersection counting from the upper left corner of the6 c4 U) K( \7 W4 N
                  ;; world.  -1 for non-intersection patches.
( e+ b( i9 V2 m) u- U" }  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.- K- h" |; U6 t) @2 ]$ u8 g
  auto?           ;; whether or not this intersection will switch automatically.
$ Z& c1 ?+ h& \) X                  ;; false for non-intersection patches.
6 g: H( t8 V4 {3 w2 e3 N7 r; C]
; K6 X- x+ j' V3 H. z/ _% g5 \  C& L% S  q' m# I+ U- `3 F' o% G
% h7 H$ J4 E1 Z0 }
;;;;;;;;;;;;;;;;;;;;;;" u. K) U3 v! ~1 e) D! `8 H
;; Setup Procedures ;;- r5 X2 i* K, s6 _! B
;;;;;;;;;;;;;;;;;;;;;;
1 @* \7 ^' d) u. d: b
/ N) P3 t2 i( y+ v# r1 z;; Initialize the display by giving the global and patch variables initial values.; [4 h+ K8 j0 n: M/ t% p
;; Create num-cars of turtles if there are enough road patches for one turtle to
6 j; |* s: [, M: Y;; be created per road patch. Set up the plots.
9 s  R$ W0 O3 B) f0 Q3 bto setup
! Q- h% S* Y" A, f% [# ?2 S  r0 X  ca( ^8 Q) b( i+ I% y  C/ L
  setup-globals0 t: Q( X4 ]* ], e2 Q; L

1 z  N2 q0 c3 Y8 t. U  ;; First we ask the patches to draw themselves and set up a few variables0 {* B* r: g2 e! P' x/ k' x
  setup-patches
% P) A- H6 q7 |7 [& j' j9 K  make-current one-of intersections! C+ C# f, K" u, Y4 e6 Z/ l5 S# d, D
  label-current. B  o; D& V7 f9 |% G; {2 b

" _4 l* y. L$ e9 {4 s' o$ R6 ?9 ^  set-default-shape turtles "car"/ ]' Q7 i. Q7 ?# m- A" [
5 f) d! q3 i2 z) O! S8 _  T
  if (num-cars > count roads)
; a$ Q, N' v5 m( b  [
3 ]+ b7 W9 j7 A: Z4 \9 u    user-message (word "There are too many cars for the amount of ", e* t% H% F% C* T% T9 Q" r5 V
                       "road.  Either increase the amount of roads "  X6 b: N/ ^8 n# r4 R( O
                       "by increasing the GRID-SIZE-X or "& f/ O. O/ d' W5 U* Z2 C
                       "GRID-SIZE-Y sliders, or decrease the "
( c% S( \2 _+ @/ b, [3 O                       "number of cars by lowering the NUMBER slider.\n"# T+ A7 l, V4 q' V$ N3 O
                       "The setup has stopped.")
4 o4 J% m/ h* I: D9 f    stop
; {1 T! b& d  I" h3 a  c! P  ]
2 O$ E0 v0 y" v2 L
! q" j8 Y) U; G0 b, e9 x  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color: u% [$ f  I# g( a9 R% C9 Q
  crt num-cars
4 x: I3 l& D3 h* H  [8 S, X6 J; |4 e0 H
    setup-cars8 }" r( o9 n3 s0 W
    set-car-color
1 o$ s8 h: N1 h! }, U) r) d    record-data
" }1 p2 a7 ^" p$ m5 `! o  ]# z/ v( T( H8 L* A, f

- k/ |) I0 [% J- q. O) ?. M- w) r/ t/ D  ;; give the turtles an initial speed
4 O2 I# F9 o! N& f! P; {2 S  ask turtles [ set-car-speed ]
9 T5 K& o! n1 ?. U. D* F, A- u) k% V& o- o0 }; V% }6 w
  reset-ticks% w/ U# Q. H& }9 o3 y$ D+ j
end
# |5 v! g5 e' H# _+ }9 F! j! d, f5 x4 L/ J
;; Initialize the global variables to appropriate values
4 a1 ~/ X) W4 Nto setup-globals" q+ s& h  T. Z
  set current-light nobody ;; just for now, since there are no lights yet1 `: W3 J/ F5 _; r  t
  set phase 0
( X& h3 {1 ?& L$ l; U  set num-cars-stopped 0
1 d9 V& G3 Y: P" [  set grid-x-inc world-width / grid-size-x
1 D' l# G* m0 M9 t  set grid-y-inc world-height / grid-size-y3 r+ D% G1 ]2 `* K
# e7 E9 |1 z# i& w3 L
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary" C) ?& E( b3 a; y& |1 T% b7 t* ^: z
  set acceleration 0.0997 C* N* J4 |, n
end
5 t3 b0 C3 J! c0 a$ ]0 }, I% a+ X3 V# K8 W( R4 l
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
( r- H$ h% g' m2 m7 C+ Q;; and initialize the traffic lights to one setting& E1 M) ^3 ], }9 G, |
to setup-patches7 R: b- Y$ l) `& r4 t6 g
  ;; initialize the patch-owned variables and color the patches to a base-color0 n4 Z& `4 Y5 i$ z5 u1 E
  ask patches
: H, l* m2 }6 t; z  [# {3 X* P$ S* X  ^( K4 n5 B
    set intersection? false
- E' z9 q" Y5 e, c& P* n. N    set auto? false5 b, C7 ^- ^4 _% ?) c9 _% \
    set green-light-up? true: l# z3 {$ o3 e  ~1 Y
    set my-row -1$ B: B$ U5 ]% U$ |* [- e& g/ y
    set my-column -18 \- a& W: u6 D6 e
    set my-phase -1
8 m5 I& n* U% o    set pcolor brown + 3+ F3 }1 t$ `: S* c* z2 s
  ]+ v/ d6 M. x4 I% J

! j. i6 \0 S7 @" D# p5 o  ;; initialize the global variables that hold patch agentsets7 f1 v$ X% ]) C+ f! \' ~3 \$ z
  set roads patches with
7 \, R* w$ q3 c5 L    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% e3 Y, b! ^% S( w% `
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)], l6 e  o+ C4 s, t( g. \7 l
  set intersections roads with) [* g. F; \% y2 K( W4 U7 y! U
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
% b, Z8 x  n0 X3 C8 {0 T    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( Q! u: h8 T! V! H% l' k3 |0 i
" \0 z6 H; A! T; O, K' Q  p; v% E6 s
  ask roads [ set pcolor white ]  J6 r5 Q6 u) }) B, Y
    setup-intersections) G! V+ }$ X& O) {
end
3 Q6 O# i; d! [* J; d其中定义道路的句子,如下所示,是什么意思啊?
; ?4 R+ Z" Z6 o3 F, F1 ^7 f2 r; i set roads patches with) z2 K/ W2 @  O' I8 ^2 Q* N
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) z2 M' P% O/ M" I. [) S% ?    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 _3 y7 X/ j9 J$ v) q8 V6 ~* Z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, 2026-5-21 06:38 , Processed in 0.017360 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