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: 8069|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。* C3 L: e3 S. }
netlogo自带的social science--traffic grid这一例子当中,) M' L( I6 l+ x- u
globals
5 _, l! f8 Y0 Y4 X  [[- t6 s: V( H, s: J3 J
  grid-x-inc               ;; the amount of patches in between two roads in the x direction. x9 v2 ^4 q# u8 b7 b2 ]
  grid-y-inc               ;; the amount of patches in between two roads in the y direction
* d9 G: J4 n  M* r  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
6 a2 Y5 k( o2 N+ x- W                           ;; it is to accelerate or decelerate7 f* h' N( b( Y6 V  y) \6 s$ M
  phase                    ;; keeps track of the phase
7 g6 o* H' U7 Y8 u4 k  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure; U7 J  l% [! \+ Z# ^% a
  current-light            ;; the currently selected light6 y$ o0 }; U3 i8 `4 }5 x/ [
% L, ^4 ~' r+ K# F: H% Y
  ;; patch agentsets2 Y4 R2 j4 j& [2 T% Z$ I
  intersections ;; agentset containing the patches that are intersections
2 p+ g3 H$ C0 \& U& X( u  b; y  roads         ;; agentset containing the patches that are roads6 V: G( a4 x4 d, u/ n6 `0 ], b
]
. Z& f6 k: {( Z$ o6 q; C+ D1 F
! |# ~. `! h( Tturtles-own$ [4 g( h$ x6 A4 K3 t* Z3 e' m1 U
[
- o5 B& J0 v! {- C4 s4 _( p* B' h  speed     ;; the speed of the turtle8 w0 ~- x0 T5 ?4 ?9 C; H* _7 u% u
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right% d$ U) K9 ]+ P( I
  wait-time ;; the amount of time since the last time a turtle has moved9 R" M4 V$ M# m
]+ L- F  s' G! E$ N1 ^) d& l

: R4 Q& N) P0 l- R, f1 O4 Vpatches-own; E+ [6 G: m, h0 C; ]2 S* `
[* x1 E! u+ d. y, O% r
  intersection?   ;; true if the patch is at the intersection of two roads
( K4 C5 q- v4 t8 ?  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
$ b) ^! l6 {" B! n0 U. x$ V1 G                  ;; false for a non-intersection patches.+ l4 _5 ^* c: n; c; a7 b, j
  my-row          ;; the row of the intersection counting from the upper left corner of the
: f- U! e0 v5 L' o- `, G6 U                  ;; world.  -1 for non-intersection patches.
% \2 H8 ~) q( J$ V+ t  my-column       ;; the column of the intersection counting from the upper left corner of the
% `9 K5 b( V/ A& }, y5 _5 c* Y                  ;; world.  -1 for non-intersection patches.
8 ?/ j! W4 v/ V# ~9 n9 Z  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.. S6 S! t4 p: r
  auto?           ;; whether or not this intersection will switch automatically.
0 H& j. K) S! y' m                  ;; false for non-intersection patches.
1 S; S( G3 V6 t" g; Y# T* D4 p]: b# {4 ~( f% W1 C8 f- E3 K; ^
# K' s' f% n0 I8 L. N; @

" y2 {8 q) [3 B* p;;;;;;;;;;;;;;;;;;;;;;
5 t+ e/ i) i3 O5 I. {;; Setup Procedures ;;
! h  ~3 Q: t) Y! O% F$ v' H2 d;;;;;;;;;;;;;;;;;;;;;;
  v/ R! v4 t0 X" O( ]. N
& W" _# o& \4 S! ]0 M/ q;; Initialize the display by giving the global and patch variables initial values.' Y9 y/ [9 [: n8 p2 K# O3 o7 J
;; Create num-cars of turtles if there are enough road patches for one turtle to, t; \) a- G) g6 t' @9 d5 Q: e% g
;; be created per road patch. Set up the plots.6 p8 B# @  q5 m+ L
to setup" D! A0 P% e- ^6 q
  ca" ?2 |  E3 |8 n5 t1 |2 S6 ]
  setup-globals
( g& i6 w6 u/ \1 X& \) m3 }8 p: W
4 z! A* q# V" h5 @6 m" G  ;; First we ask the patches to draw themselves and set up a few variables& F+ H6 n  M( q/ v
  setup-patches# i# r( ?7 @4 g9 c" ?) x& g
  make-current one-of intersections
. M  I. W* X+ s' W3 |. o  label-current% A3 V0 \6 c; G$ R$ }/ O1 E

1 r* b: |2 l$ P- d  set-default-shape turtles "car"
0 O, K. H" `; y: r7 L
: }9 |9 |' o" E  if (num-cars > count roads)3 Z( k+ Z: C' Z. f7 h0 I
  [
) Q( e( E- R+ C" |+ L6 _: E' A7 g    user-message (word "There are too many cars for the amount of "1 o5 G3 ]  O$ j$ ^8 F
                       "road.  Either increase the amount of roads "1 p4 X) z( o* e
                       "by increasing the GRID-SIZE-X or ", X0 Y) M$ U8 j3 y  ]* m$ G/ Z5 ]
                       "GRID-SIZE-Y sliders, or decrease the "! H8 ^$ V! {" p2 z
                       "number of cars by lowering the NUMBER slider.\n"
2 u  e, D0 A* g' i1 J- S                       "The setup has stopped.")1 j9 w5 }! _$ t" p" M( }' v
    stop
7 t( ^( @7 d( d7 {3 S; t  ]! c+ p6 ]5 E2 s5 o# ?
* ^! @: T2 Z9 `! n1 j
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color% b$ f9 Z0 s3 B3 a
  crt num-cars
4 P9 @# {8 v8 B2 c( [  [$ p: L* K3 p( C+ n, x
    setup-cars
2 `; Q1 j& \8 [' F; F- }    set-car-color
: K9 v- S$ `7 N    record-data
9 \$ G$ S1 L% T& c$ w  ]" j5 i. I5 O* W5 s
$ a# l9 |- K. I6 k+ S) i
  ;; give the turtles an initial speed
# o- ^4 ?2 k6 q5 v  K' `7 }/ G( r  ask turtles [ set-car-speed ]
( m1 t- ^# ?9 W2 x  j" \) u3 s" q9 r, Z- w2 D5 ]. e7 {
  reset-ticks
# G' u6 U5 w4 |5 B  Bend( ~; u( D. r5 X' \: T

9 \- R. S9 x% w;; Initialize the global variables to appropriate values" @6 u9 D( R0 e/ K1 J% x
to setup-globals2 L$ B: u' }9 L3 @
  set current-light nobody ;; just for now, since there are no lights yet& E. v# ?" Q& T1 z& J$ I
  set phase 0
9 c; c( ~* `0 Z: I- H' m  set num-cars-stopped 07 ~4 F& C0 }2 ]1 F* W9 u, {
  set grid-x-inc world-width / grid-size-x3 A" t# H  O7 P% {5 a
  set grid-y-inc world-height / grid-size-y
( f$ L7 T/ I$ P$ R7 L4 `! n' q" l3 G) z8 q* }5 u" L
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary. z5 i, r1 s% n$ R$ m4 o
  set acceleration 0.099
" Z; B; Z7 V* n' ^  `5 ^end
+ G6 y1 T3 M4 W! G3 k5 f- [: _, M+ m8 q( t3 [& L% O
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 E: [7 o* q- W8 j) A/ m7 q- e
;; and initialize the traffic lights to one setting# I4 T6 K# P+ ]: |: a
to setup-patches
9 g' x6 Q$ E% e* a% O  ;; initialize the patch-owned variables and color the patches to a base-color- K) B8 l. D) d5 |
  ask patches
+ \2 ?. ?2 K2 [8 [: ?, {  [4 h9 ]: N9 s1 [$ g4 Q5 o' n8 k
    set intersection? false
, U+ N7 w- s( T% |    set auto? false- O% |3 [/ E3 ~
    set green-light-up? true" r6 V# M7 m; ]) O# g0 \* F. n9 w
    set my-row -1
+ d  X* q3 X0 h    set my-column -1- f" U2 D. U/ L) _3 Y
    set my-phase -17 G9 a" q3 E. V* J- a  g0 w$ Q
    set pcolor brown + 3, H& ^6 u! S; c% ?3 Q5 Y+ T9 S
  ]
5 \, ~& y" W  U5 S- }2 I6 |/ a' j5 ~) D0 {$ P0 ~: l
  ;; initialize the global variables that hold patch agentsets3 I1 ?  t9 O% g5 \7 U& e" _
  set roads patches with
6 ?% L* ^5 h: K- j1 ^" ^    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or+ _: w+ y6 z1 I0 v! P, A
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# i6 x; Y/ d  g7 D2 V' j; E: i  set intersections roads with
$ }: C$ D( l, k2 n/ }# u) c8 }    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and" y. p* Y1 u3 Y
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; E" c" f. r8 u

# I  E$ q3 ~! t# B$ {3 s; k8 Z9 w  ask roads [ set pcolor white ]  x  m! H; `$ G, b
    setup-intersections  r/ s$ |5 h9 k( C/ b0 z. o% m
end
6 d8 R9 t$ |5 B( J% h% u其中定义道路的句子,如下所示,是什么意思啊?1 u' @; G) t2 l7 t8 m/ V% ~; P
set roads patches with
8 k5 E) q7 i) u% A' O* O, R    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) [7 o3 I/ K7 G- v9 M
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
( `/ G' w8 u0 n; e3 y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, 2026-1-30 10:46 , Processed in 0.015252 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