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: 11202|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。) z5 Z. T+ J6 c. N+ Q1 Z/ ~/ K
netlogo自带的social science--traffic grid这一例子当中,
6 _/ F8 J9 }6 ^) T- u! rglobals
3 V  T- M* Y. V[
  T5 l; Q& K9 q. Q, f+ R  `  grid-x-inc               ;; the amount of patches in between two roads in the x direction; C5 A5 Q/ J, K1 ]
  grid-y-inc               ;; the amount of patches in between two roads in the y direction& e' R# Y: h$ ]* w7 \
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
+ P& V4 W6 l2 |0 q4 ]: |                           ;; it is to accelerate or decelerate5 O9 Z2 V: d( Q, I. H
  phase                    ;; keeps track of the phase
: r& ~8 P6 @* j$ q$ b/ M+ d  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure& Q2 ]# m7 F, B, F8 U: k& m
  current-light            ;; the currently selected light
' W$ p, F. G3 s4 M
  g( p4 ?* u$ v" X2 H0 x  ;; patch agentsets3 y& R9 t) e* _( n* ^
  intersections ;; agentset containing the patches that are intersections5 a! D3 H, R/ ^2 E4 X
  roads         ;; agentset containing the patches that are roads
, P" t$ z: X- P/ U0 b* x]
8 ]2 d! A# B2 L' K, U- z& t/ P6 p
1 X* t% r6 R! r' ~( Yturtles-own5 q. a+ C. c% R) \8 p6 ^
[( I. p, h) r. ?: f
  speed     ;; the speed of the turtle  L8 H5 z2 V! F1 i: x$ z
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
+ K: {5 n7 z3 w* c" ]  wait-time ;; the amount of time since the last time a turtle has moved6 A) q2 q6 u* v) C7 t7 r0 s) {4 Y
]
/ U! [9 p' ]3 z
( |4 z! E# w+ u" t, L$ S/ Lpatches-own
) D, S+ e9 p  |/ @- e[
' _* E2 w( R5 x6 T. t, [  intersection?   ;; true if the patch is at the intersection of two roads4 n7 J& m/ f5 B7 ]
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
  j/ D4 Z' U5 X8 |                  ;; false for a non-intersection patches." M7 V; R5 y5 D/ L3 Z* c1 n
  my-row          ;; the row of the intersection counting from the upper left corner of the/ j$ g; n1 h) s5 I
                  ;; world.  -1 for non-intersection patches.
0 W0 X+ S) B% m7 D. \7 X  my-column       ;; the column of the intersection counting from the upper left corner of the2 l: p* Q$ P! A9 T9 F
                  ;; world.  -1 for non-intersection patches.6 l' S" {; t$ J' _
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
% |- }* m6 j0 O- I4 H! }  auto?           ;; whether or not this intersection will switch automatically.
0 Z4 p4 C" ~7 ~4 v+ ]% r                  ;; false for non-intersection patches.: m9 T4 d6 p; \2 O; q) k2 a2 t- H
]# O" z& m) ?. n) Y* m
0 X7 N/ O( o6 K3 ~+ y' R

/ P5 \# h1 S7 @) Y( [- i;;;;;;;;;;;;;;;;;;;;;;8 G2 E+ y( F& y; w2 |5 c1 F! m
;; Setup Procedures ;;# I' u2 H. b5 Y5 Y. r# ~( l' S
;;;;;;;;;;;;;;;;;;;;;;
6 T$ y- g' D6 t5 c8 U" ]
& _. N/ Z: r. I" W$ P5 Z' r3 [;; Initialize the display by giving the global and patch variables initial values.* @8 f5 S2 H" P! R6 a, _$ g4 S0 F- o
;; Create num-cars of turtles if there are enough road patches for one turtle to5 f% x7 T& {9 |
;; be created per road patch. Set up the plots.' g/ R" |+ x6 B- o- m  c
to setup
, s) d9 a+ L0 G- g5 [6 R  ca
' o: G. N( b& _; s. u( v8 b  setup-globals
) q0 u' D- r- }/ A& E
8 p) p1 w2 i. @' n2 e  ;; First we ask the patches to draw themselves and set up a few variables0 X2 H+ a0 |& g9 S  F: J2 M. G! n
  setup-patches+ ~) T* J% M$ A) c, J9 ?
  make-current one-of intersections
+ B0 n' B9 r+ v1 o; @  label-current; c( {- ]) F6 ?2 ^9 l- k: v- A
( X: ]' _' o% I  v) Q7 l. D& `1 y4 k* u
  set-default-shape turtles "car"$ H4 K+ S0 s6 g4 K) D! o8 o+ F3 G

4 C  Q$ j& [+ J. j  if (num-cars > count roads)% ^- L! r# o* R
  [+ m. A- P- A) z9 T' m" K  I
    user-message (word "There are too many cars for the amount of ", s$ }3 U: q& {* h9 b
                       "road.  Either increase the amount of roads "
4 P! l) Z( w( `/ d5 i- k                       "by increasing the GRID-SIZE-X or "
6 A1 r! j, y! H! j                       "GRID-SIZE-Y sliders, or decrease the ": A2 t8 \' `8 k0 M( A! a% }1 I+ J0 }
                       "number of cars by lowering the NUMBER slider.\n"' L3 W4 M5 e9 u8 z- L
                       "The setup has stopped.")
, s$ V% a4 P) s7 o4 P    stop3 y8 I6 m( W9 P( f+ U
  ]8 v7 Z8 ?: X5 _/ z6 \

  e# i! a  Z' a5 V  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
/ s" N5 H9 K  V" X  crt num-cars3 J. e' N( E% }; ~3 m0 G4 w
  [/ k# _( _9 Q( |, Y. Q
    setup-cars+ o2 K' L) s" X
    set-car-color9 s% _$ B/ `3 M, W; M
    record-data. d: K! g3 w# d' P5 Y( g
  ]
* u7 S; \* I/ X* `% ~6 @, B2 I) [' E) w4 n/ X% U4 A
  ;; give the turtles an initial speed
7 W9 y, p5 V. z) Y7 K  ask turtles [ set-car-speed ]$ C0 w9 m% t6 l9 }# g$ S

3 n7 j6 Q, ~" y, [7 z  reset-ticks
1 [3 ]0 T$ K0 y) Lend+ ^' ]9 F! J1 C; n* l- ^2 R8 W

# @# d% n/ p* X$ F4 \" ^0 j0 A2 J: @;; Initialize the global variables to appropriate values6 }4 c$ q% f4 I$ ^4 z( M
to setup-globals
9 ^9 k6 H5 F' J- ?2 m  set current-light nobody ;; just for now, since there are no lights yet
8 O* r4 R0 E( {  set phase 0% `& A/ y& k- [
  set num-cars-stopped 0) k4 I4 Y" [/ V& I  p, I2 r2 f
  set grid-x-inc world-width / grid-size-x- r% ]" l- |: J; ?9 A% ^# A
  set grid-y-inc world-height / grid-size-y
& P6 t# w2 e4 [9 c  Q' C: g# B0 E+ D
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary$ f4 O1 r, j5 J1 d3 U7 k7 k
  set acceleration 0.099
  y. s4 q5 y9 \; bend
; P2 @' z( s5 j6 D0 C. h; h/ @! s1 c5 ?
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,5 g$ c. Z5 ]& o2 m% ^* ~/ f4 Y
;; and initialize the traffic lights to one setting
) M: m! A2 d# p0 \/ f9 q( ^to setup-patches
* Y: u  J2 }+ I  ;; initialize the patch-owned variables and color the patches to a base-color( K5 i2 H  a# R2 Y) @. i( J
  ask patches
0 j% s3 ~; u) G- J6 @  [5 n; N  E5 H. b8 P! s5 [! o
    set intersection? false! R8 V% X) q0 H5 C9 w0 }3 X9 Y4 T6 m
    set auto? false
1 {1 l! V* s4 n    set green-light-up? true
! p0 J7 \  i: W6 A, c' @5 P    set my-row -1- V* p* R* M6 F( D
    set my-column -1
& ]1 k8 h- ?- a+ \& u/ o    set my-phase -1
$ j( E3 T/ r, T' ?& \5 D! _% _    set pcolor brown + 3
: _) m( r& u8 p& M/ q# j3 O  ]
3 S) w# w. \) }6 E1 W$ Q4 i# z3 e% [$ k% e( z* `6 f( ^! ?6 [
  ;; initialize the global variables that hold patch agentsets: Q' K5 S1 W$ `; {, x3 s3 U6 k: N
  set roads patches with
9 P2 j! Y5 j( u    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or( p" k+ A6 {: F5 l* e3 p2 S: e
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' V4 g+ s- x/ J+ c( f& c0 V& x" x  set intersections roads with% F* g  F0 ~& T, I4 L3 G. ?
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and/ G* M. o, z9 v' F7 U- K1 T
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& O( z4 R/ c7 [  f: K; Q
$ p3 w: [7 J3 f$ e3 ~- j8 V- G  ask roads [ set pcolor white ], x, L2 K2 q; O+ [. E/ v& W0 Z0 l9 ~
    setup-intersections6 r  L6 ]" B. R/ Z2 O  K% z
end8 ]' N& ~6 P' e( t  K( E. _  G
其中定义道路的句子,如下所示,是什么意思啊?
6 ^' t0 \8 C7 U  I, H set roads patches with2 e& q) v* h2 ?: O' B( b
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" Z2 \" m" Y" b( e    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, ?: C$ K. _4 F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, 2026-7-19 04:04 , Processed in 0.015478 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