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: 8285|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。" P8 a  B9 }/ H* s
netlogo自带的social science--traffic grid这一例子当中,' M/ x9 D8 q# C6 X. N
globals. Y* _# A: S( U7 ~, t& G
[
& U( F9 |( M) Z# g  grid-x-inc               ;; the amount of patches in between two roads in the x direction$ D  P6 c* d1 {8 C
  grid-y-inc               ;; the amount of patches in between two roads in the y direction" m9 e# B6 P/ Y, ~1 H! ^; E" D( ~
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if: }. V4 Q: q5 X/ K+ H9 x. ?" _2 g5 S
                           ;; it is to accelerate or decelerate
% V0 h5 e' w; H1 g  phase                    ;; keeps track of the phase
. y9 v+ A5 s! W! d0 i7 i" g% L" D: U  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure! ?  T$ B$ Z0 O3 n& F( ]% t7 e, {
  current-light            ;; the currently selected light
$ R: j$ j8 T8 j$ H, p9 _( [
3 N* X+ y+ a- X  ;; patch agentsets* S+ |! [2 S8 @6 E1 d
  intersections ;; agentset containing the patches that are intersections2 i, C9 n! Z, V' `# Y
  roads         ;; agentset containing the patches that are roads
( c: b2 p3 J9 z7 A]' ?  k+ U! b: X7 U$ L! D
1 G3 u' U. E# b; i, c
turtles-own6 C! X. n+ }8 e' I  I
[
4 Y, Z/ q) @8 O9 B5 Q" o( A0 e  speed     ;; the speed of the turtle
) U. u! M! k- \$ [$ a  up-car?   ;; true if the turtle moves downwards and false if it moves to the right4 w' y0 t7 R9 Z" \3 y, C8 f, C
  wait-time ;; the amount of time since the last time a turtle has moved
6 G/ R+ U3 Z9 ?: t  j: Q3 i! A4 u]
& U8 P6 o. K( W! [! a0 j) f4 h- y
2 m" y; p1 M8 j' w5 F& G) l6 W1 f7 lpatches-own( m' j  v6 V1 {- t
[
) j' J; q8 m& t& I  a8 j  intersection?   ;; true if the patch is at the intersection of two roads2 d7 D; P) E2 s8 t: n% ?5 a2 g! \
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
3 j4 r3 r3 e* D: K) S& b                  ;; false for a non-intersection patches.
! U8 z' o1 O4 n6 e7 i8 @  my-row          ;; the row of the intersection counting from the upper left corner of the2 r" j1 h( y$ L5 r
                  ;; world.  -1 for non-intersection patches./ W' |6 _  w3 \+ g. V6 q# M. ~* U9 f
  my-column       ;; the column of the intersection counting from the upper left corner of the
5 T( M) B  D9 H                  ;; world.  -1 for non-intersection patches.. |( F% M8 S& Y2 ?( k$ r) z# F/ c0 }
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
& d6 C  G- n5 c: x  auto?           ;; whether or not this intersection will switch automatically.
8 e+ s. q$ ?" G  |& G" `7 K  m                  ;; false for non-intersection patches.
# z  f, j2 V8 c( X: E]* x( m3 e6 i* d6 n# k! K

2 _* [) h5 ]) _% h! x2 V: S/ M6 E4 R
;;;;;;;;;;;;;;;;;;;;;;
( K3 `0 R( F* p' v4 Z;; Setup Procedures ;;8 i! w  |) P+ ]/ T
;;;;;;;;;;;;;;;;;;;;;;
0 d5 i- n6 i# l9 z' h7 N* X1 K. N/ @* Z/ {* q
;; Initialize the display by giving the global and patch variables initial values.) n9 V9 \2 ]( A5 S/ {& ?; c
;; Create num-cars of turtles if there are enough road patches for one turtle to
: J# m5 h3 ]9 n) ]- e$ R;; be created per road patch. Set up the plots.
! h  W5 \2 v& u* T: o$ ^to setup& K/ O. {; m. ]1 _7 l: x" O
  ca4 L( t, @" ]. h
  setup-globals
; u$ v  i" a* v$ i* Q1 N
0 ]- K, x2 {4 s) o8 C& i  ;; First we ask the patches to draw themselves and set up a few variables0 ?# O9 D' p/ S9 u% i' l5 U
  setup-patches" g( _( I& p2 A2 S% a# a5 L/ x. E& N& S
  make-current one-of intersections6 \+ {. ?- g! C
  label-current
2 m9 m- }6 a! n! Y# h, ~. ^* C% |$ X( T' S: x' y  A
  set-default-shape turtles "car"
: Z2 f& m( a5 ?# O2 ^& C$ g  ^: N- r
  if (num-cars > count roads)
; h4 P5 D! A5 ^  [
, l8 {. [3 Z2 v! R* R) Z* I8 r7 D2 B    user-message (word "There are too many cars for the amount of "
# S9 ^9 W& @4 r                       "road.  Either increase the amount of roads "" ~) X- m# y( N. d1 z
                       "by increasing the GRID-SIZE-X or "
1 y: [; z2 c) S                       "GRID-SIZE-Y sliders, or decrease the "
* _' }% F9 a! `% V1 S2 l, J, K' o: D                       "number of cars by lowering the NUMBER slider.\n"0 K/ s' G, g& `+ f1 m. L( N$ J
                       "The setup has stopped.")9 |' K0 t% C/ a6 k( s* c
    stop
. H: a4 V% O" x; U; ~  ]- m# c* j% d% @: P' \) j

  w' c! y# ~; U. c9 t  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color9 _/ a4 M/ C3 T/ q) I; O, }% s5 z
  crt num-cars
* `7 J6 u/ [. ^* L% D7 Y5 z9 K  [
. s! r. ?+ E* V5 g7 t9 p    setup-cars
8 Z3 X- T1 g, a, l: s  l& n$ A    set-car-color0 A6 C2 n2 F  g( \. ]- J  B$ G% N
    record-data
0 v6 l7 h  f0 h; X# V  ]
9 X6 Y8 u6 a4 k( g4 }
6 h7 A+ W8 x4 E2 f/ X, }$ U( h  ;; give the turtles an initial speed3 k9 l& {5 o9 ~9 _$ ]* s
  ask turtles [ set-car-speed ]
* `' _( g% O' A; g# o8 u8 L0 f& D, a  {, `
  reset-ticks( a6 o) g* A4 c: k9 u. T3 a- D8 F
end. Q3 {% l" L7 v" |/ i4 X( W
! i( ~7 j- g1 z& S
;; Initialize the global variables to appropriate values6 {0 b6 y! A5 y5 V, P( B+ G  h: H( w
to setup-globals( P: G  _8 W4 U- {
  set current-light nobody ;; just for now, since there are no lights yet# c! z  Z! D8 A2 Q; k
  set phase 0
5 p0 \, M# T7 N6 Z  set num-cars-stopped 0
/ x) B) K5 v8 g: Q  set grid-x-inc world-width / grid-size-x
5 |5 L, j& O" o- o& B1 P/ \  set grid-y-inc world-height / grid-size-y
* P8 X5 {( l* f) Q. J8 B2 B  N* n5 e2 ~/ o
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
+ w3 z# C3 f8 _$ A  set acceleration 0.099
; F  n( I( \( R3 T- N. G0 R3 Eend
8 ]& H+ A- l# V2 E( k
) c8 N) z0 e" d- M& |6 H+ [% ?' a;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
$ h8 T, R# z+ a7 p8 r7 V$ e8 C( V- L;; and initialize the traffic lights to one setting' i+ Z$ p! ], S; J
to setup-patches
* j' h% x) d7 p! j6 h; j1 I. _3 B  ;; initialize the patch-owned variables and color the patches to a base-color2 w) P- P& e; u. G8 \1 K6 w
  ask patches" [: i* d2 k& p7 B  ]
  [
0 f3 A  i! H8 _$ ^% q9 t4 R    set intersection? false
1 c4 v% \. S! k$ s: X    set auto? false5 E: w6 \+ E8 [! `' V
    set green-light-up? true
; p; _( y& e: }+ T" b    set my-row -1. V9 x0 f6 J- A2 h( |! `9 m* n9 y
    set my-column -1
6 a" C3 Y" N' g, J    set my-phase -19 m# ?. k$ ]! R* u# H6 C
    set pcolor brown + 32 A& x: e/ ]' `! |/ z6 B/ J
  ]
! Z9 r* Y4 V% b/ q) f- b
8 k' m% `2 h& C! C6 N; J  ;; initialize the global variables that hold patch agentsets
* z: n5 K- g' I! i% n3 k3 ^  set roads patches with
! k; g$ g: y. H5 I5 s' [8 N6 h1 D    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% e. w. I& L* C: D    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ p. v: ?+ {' @3 [* s' Q+ u
  set intersections roads with1 H% s- V/ S# {& L& N
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
6 O) `+ M& Z- I    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 }; Z) K3 |: A1 ^9 Q: _
0 x. H& d7 f! `, ^
  ask roads [ set pcolor white ]% B0 Y$ |/ b8 F5 I
    setup-intersections( ^' |, i: y9 K- M
end! n. [& l4 d  L6 t+ U! c
其中定义道路的句子,如下所示,是什么意思啊?, @2 O0 j- G8 f# l. W! J1 [3 z
set roads patches with" v0 ^5 @: L0 J
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 h. Q5 A* `- [: a
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# p  @, `2 T0 j+ _7 ~1 ]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, 2026-2-10 12:13 , Processed in 0.018182 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