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: 9309|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。. l5 d5 ^( X# M; s+ I
netlogo自带的social science--traffic grid这一例子当中,) g& S, ^" `9 Y$ b4 h; a! f1 I
globals: T1 s8 @6 Y+ H, i. f
[
$ G3 h1 q2 ?1 D) m0 J; K. O  grid-x-inc               ;; the amount of patches in between two roads in the x direction
$ m3 b2 H- z  }1 A" f, U1 X) x  grid-y-inc               ;; the amount of patches in between two roads in the y direction
! w& R. {5 J) g# |% m- k( w' K  acceleration             ;; the constant that controls how much a car speeds up or slows down by if; Q: H2 ~! X, X9 \& B  z% b' D
                           ;; it is to accelerate or decelerate
$ g2 A8 f1 x. z" V: U2 w) [  phase                    ;; keeps track of the phase
# @/ L% [0 [$ P+ H) P6 y  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure1 S* V8 O* U3 e! T8 @1 T
  current-light            ;; the currently selected light
9 c' l4 q% N( g6 W* T" Z
& X, D: q5 I, T, p2 y5 F* M* H' |  ;; patch agentsets
8 x* l0 T5 p+ i! [0 C* m  intersections ;; agentset containing the patches that are intersections, P* M5 M$ P) a# c( X
  roads         ;; agentset containing the patches that are roads
! j' ]: @( s+ F5 m; Q( F]
; \$ y; @! q) h2 P# N# _# \( y: w% t( O; J
turtles-own
% @3 ?+ }% z# v& ?  I- M0 w4 N4 Z[3 X% v: x, D% W
  speed     ;; the speed of the turtle
3 l6 F9 y0 P. O. |( q  up-car?   ;; true if the turtle moves downwards and false if it moves to the right# o# a% @# F: V' [0 e
  wait-time ;; the amount of time since the last time a turtle has moved
/ T. K; }+ V6 R]" M! T0 k( v5 q

, b6 c' H8 s- F! P- I1 ]( hpatches-own
7 z! }7 P& e8 M. x1 s6 I[7 o) K* k  y9 M( @7 o
  intersection?   ;; true if the patch is at the intersection of two roads
3 {# `( p: \7 d: F  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
( Z. x! S) Q# k% [, B* x8 ~                  ;; false for a non-intersection patches.
' c( ^% s2 a* u8 ?  my-row          ;; the row of the intersection counting from the upper left corner of the  ^, `  }$ \7 |& T
                  ;; world.  -1 for non-intersection patches.$ [: o. R1 @! d/ C: Q5 z+ W/ P
  my-column       ;; the column of the intersection counting from the upper left corner of the& ~. r( H  u4 [. `! L
                  ;; world.  -1 for non-intersection patches.! F1 u* E1 l+ O0 W
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
* Y, R! z6 G8 n' E  auto?           ;; whether or not this intersection will switch automatically.+ ^/ s9 E$ k+ B- r
                  ;; false for non-intersection patches.) J4 `: K' ], F
]
  w" {- U. E1 [2 V: }3 V' O( b- A9 k+ W4 @, `+ T
: ], O8 S+ k; Y$ d% T
;;;;;;;;;;;;;;;;;;;;;;; M" f  i9 _3 N9 g$ R
;; Setup Procedures ;;1 E/ X# S6 k' o& V% J  l
;;;;;;;;;;;;;;;;;;;;;;
8 _& [6 ^8 W2 n5 D1 b6 L- g, C9 W5 H8 U  X# @: q9 E
;; Initialize the display by giving the global and patch variables initial values.
% ~2 ]4 Q5 c6 Z8 b0 F9 s* M9 k4 t( A4 V;; Create num-cars of turtles if there are enough road patches for one turtle to
! `: G2 L  e) z! p) q& c6 w;; be created per road patch. Set up the plots.
% P; L$ ]6 S4 L$ S, z8 M4 oto setup# F) S/ e( q! V" d
  ca
6 K' F  ]3 G& L9 `' D! J  setup-globals
3 u/ F- R1 [6 z; j' }# D. W& M2 R/ f4 x7 R* C# C" _' m
  ;; First we ask the patches to draw themselves and set up a few variables
% m7 h, p* D  w2 [3 i; I  setup-patches; ?4 ?8 r# w' {: V
  make-current one-of intersections: }  [- w6 U- r8 l0 j: f. ^  k
  label-current4 c6 X: @3 G0 [$ t  l

* J6 J" B: e' T: B  set-default-shape turtles "car"
% A2 n% S! u1 }
, V! U% y9 c, s! Y" f/ y  if (num-cars > count roads)" {: s( m$ v+ a3 ?, q
  [. C6 ?" x0 L, `( p9 H! p
    user-message (word "There are too many cars for the amount of "
4 n& C+ j/ L3 M/ x6 Y: T, C# k                       "road.  Either increase the amount of roads "
1 v5 O. m1 }9 K' D                       "by increasing the GRID-SIZE-X or "
: \, z  v/ M2 A+ j& [4 Q                       "GRID-SIZE-Y sliders, or decrease the "
# F3 s6 A/ n7 O7 m                       "number of cars by lowering the NUMBER slider.\n"
0 V; q) w' a- m; u0 _- ?: j% X6 q                       "The setup has stopped.")2 p- u/ h& R: O
    stop0 L: a1 v% E* ], d
  ]
% k; ^. ]: N+ k$ b$ _
. l" L$ v4 P0 N2 g/ [4 |0 L% K# C0 F  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color/ @- F8 z/ c7 A/ G3 n
  crt num-cars
, e! @" }" z3 u  [! n3 y/ V9 u) r  _/ J8 z* `
    setup-cars
: q* d% K7 F* A! {+ L! l( r+ b5 o* u    set-car-color
0 C9 [& K5 h# F& y* m3 R    record-data
4 K: x- @& }9 l& H2 O  ]
( N8 F2 T( `% q' j  j% H7 b' P6 p' m0 d
  ;; give the turtles an initial speed
; j# j, c* W2 B5 t, F  ask turtles [ set-car-speed ]
& |/ W+ l2 b3 C; I3 L3 u$ d6 p9 d2 E
' n" M* K; n# Y8 m7 j  reset-ticks5 S3 j, s3 s8 J* a$ h, D& D' C* }0 W
end
) D% U" Y5 C* U. s' P4 J. T2 W+ u/ R. ~0 P  J/ K
;; Initialize the global variables to appropriate values
0 H* c( G; U! fto setup-globals+ G0 M' y/ \: y) _) l0 j3 L
  set current-light nobody ;; just for now, since there are no lights yet
1 U5 w4 _3 N9 L9 ]8 I  set phase 0/ D0 r7 J" A% H% y; {3 T! Z
  set num-cars-stopped 0
5 M# t9 k, Z7 e1 |" H/ ~  set grid-x-inc world-width / grid-size-x
+ @) Z& I  _/ y  set grid-y-inc world-height / grid-size-y( x& A- j7 O# s+ \9 H: w! m) V
" c: p/ m( K) G8 v
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary7 Q" J9 I) D3 D. U
  set acceleration 0.099
; O3 V, t- c1 u0 H, p& Hend
! k# b+ @: n* }2 y. D
5 ^8 Z2 k' v/ k3 p/ @;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) q9 H: U0 I& b# a
;; and initialize the traffic lights to one setting& e# E" y/ [" o0 p
to setup-patches& F4 j" P7 q; q3 b* _
  ;; initialize the patch-owned variables and color the patches to a base-color+ P$ E  j3 `+ I+ V
  ask patches& e: L" l9 Y; I9 F* N" z. \
  [+ F1 |7 p1 y% h1 `: ]& b3 o& I
    set intersection? false
8 J2 S6 j  L! x3 ^& i+ [3 k& b$ S    set auto? false
4 \& N$ N# _2 `& w3 {, Z* Q+ Y    set green-light-up? true- p1 Z! u3 C" m: v5 A
    set my-row -1
/ `) @' X" V! ^    set my-column -1' V! h. V. _9 L
    set my-phase -1
& |8 Y2 Z: ]+ m5 O) @0 e    set pcolor brown + 3
: N) X$ {% o: M$ C! H  ]
  U# `+ f7 i! g
* f, ^* O! m, R5 u# q" S  ;; initialize the global variables that hold patch agentsets
6 U: x8 \6 @8 f) n4 y' [" j4 `, j  set roads patches with. X- Z0 ?: j" X4 u
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& i) |* n0 [. Z% i- P    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 u) r5 Y2 o" L3 ?8 j5 @( ^0 h" J  set intersections roads with
: z8 W$ q: Y9 n6 X    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
; `5 O8 `* h' B( O# W/ v+ z/ n3 X2 F    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! Y3 Y, V" f9 A$ Y. N9 o; ?0 y) r5 x% [- K3 z3 J8 d
  ask roads [ set pcolor white ]
9 G6 y# k- E3 E( t, I* W    setup-intersections3 b8 r* k* p) D
end( A- {6 M- b% m1 y
其中定义道路的句子,如下所示,是什么意思啊?/ ?; a& B$ v8 ~$ o8 \5 J
set roads patches with7 ]. a/ \5 h, s" H1 h
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ J/ ]* J4 Q& G( }    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
+ d& ?7 v8 T8 K  t/ R% p* j+ b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, 2026-4-9 04:51 , Processed in 0.021188 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