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: 7124|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。! p" F- a/ W2 n7 n0 {/ y6 W  D
netlogo自带的social science--traffic grid这一例子当中,
9 I3 ~3 j2 z/ @9 C6 qglobals
1 p% A! x% b1 i6 b: w3 H  L- e[; e% ~: {4 r7 _' x7 a0 s
  grid-x-inc               ;; the amount of patches in between two roads in the x direction( i* `  h0 \( r& d, j
  grid-y-inc               ;; the amount of patches in between two roads in the y direction4 H2 ~4 n2 |0 ?. B# I
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if5 j4 B9 d8 F; [% y8 I- z1 p
                           ;; it is to accelerate or decelerate
% [; W7 f8 Z9 r- @2 v  phase                    ;; keeps track of the phase5 M4 R1 d/ |: P3 I+ b  h
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure) o7 P* A; ~* ~2 J9 M! K, D, j9 p
  current-light            ;; the currently selected light" ]) z% z$ v  T
" Q1 n8 r6 P9 E+ ]  g* }# ]& O6 |
  ;; patch agentsets& S3 X& b) O' n
  intersections ;; agentset containing the patches that are intersections
. w* t/ P- ]  ~% C9 U- c* Y( p1 m  roads         ;; agentset containing the patches that are roads
7 Y2 F8 j) I' ]; i]' f' F/ C5 d, T" x4 {

3 I( c* l3 ^0 s; o2 Q$ ^turtles-own
' D3 M0 A7 H/ {/ h/ j9 t/ U1 d[
. p# i2 o0 f1 Y7 W1 u  speed     ;; the speed of the turtle
4 ~! T( T6 U# N" n( d" ]  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
& Z1 o0 ~) @+ o: a  wait-time ;; the amount of time since the last time a turtle has moved
+ i6 ?$ n" S" s/ g2 p3 {7 c]* t( s* S( L. y
" u+ Y6 j, j+ I  j
patches-own1 h! k6 f1 z0 T  Y) S2 w
[& z4 {- c1 `: e8 E# [4 M
  intersection?   ;; true if the patch is at the intersection of two roads5 x% s9 o  G# L) x7 K2 W) R! t
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.) ~2 H7 C1 K- @  H2 I, _
                  ;; false for a non-intersection patches.
: R& i  ~. l- i& p# O2 C  my-row          ;; the row of the intersection counting from the upper left corner of the
+ n6 f7 r/ K8 O/ w% m: E; a                  ;; world.  -1 for non-intersection patches.
2 \, \4 m& _  r! v$ d6 R3 R  my-column       ;; the column of the intersection counting from the upper left corner of the
- \3 M0 R8 ]4 x                  ;; world.  -1 for non-intersection patches.' x1 z( r( V( Z
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
4 B0 J$ t3 l7 N1 y% }  auto?           ;; whether or not this intersection will switch automatically.
; J. D# N( ]/ }                  ;; false for non-intersection patches.5 y7 \" K4 {& c& ^
]
4 J. p. _$ ]) @* m; T6 L. \
& X" I" ?0 p" {5 T1 b# `4 z
, A7 p' v: ^8 b* w, B;;;;;;;;;;;;;;;;;;;;;;
( r1 g5 j. N" f3 h5 j. K;; Setup Procedures ;;
) h$ ~; S( l7 e  m- T# h) ]1 \;;;;;;;;;;;;;;;;;;;;;;
* K( s# n' }, h) E
! T: L. R! {6 q+ y/ p" r. _;; Initialize the display by giving the global and patch variables initial values.
+ U( ~; j7 o; Y' S;; Create num-cars of turtles if there are enough road patches for one turtle to: I, u# j6 g: H4 I1 q
;; be created per road patch. Set up the plots.; J9 }- B! z: a  X3 r, f# _. I
to setup
) h9 ]) X* f! E. S3 ~  ca
/ Y5 b9 w+ L5 R1 t- u: p" G  setup-globals
) W* }8 t8 E; o, J3 W/ F
  \) N* }9 g, j) R) r! n3 n  ;; First we ask the patches to draw themselves and set up a few variables
7 V7 W" T1 ^' R; ?  setup-patches
1 Y5 `2 X8 ^/ J  make-current one-of intersections
# s" g* |5 t* q  Q9 m4 ^  label-current! H# @0 W) v, M* R

, n0 R4 v. \) T  set-default-shape turtles "car"4 K3 L0 w( M! |+ G% E

% a8 O& o! n+ T$ ?; S1 O& c4 z( s$ n  if (num-cars > count roads)7 [' s9 R+ g% U/ X* J
  [& ^8 |7 c0 p! ^7 C& G
    user-message (word "There are too many cars for the amount of "
1 M# }/ |- C; V7 Q' C/ B* O                       "road.  Either increase the amount of roads ": w9 b) M, k* D5 \
                       "by increasing the GRID-SIZE-X or "
" h# ], f6 Z/ ]/ g" R                       "GRID-SIZE-Y sliders, or decrease the "
5 d3 l! ?" ], f) o. V4 l! R; b                       "number of cars by lowering the NUMBER slider.\n"* ]+ D/ q% w! e0 d0 Z! X. D
                       "The setup has stopped.")) v( G' |, R8 k( H" i# b
    stop
! j  J- R  V# v; M  ]
# y; I2 g" C3 [9 \( F% k$ Z# _8 h; F
, p  \' F  C% s4 O  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color* s1 a+ B& f1 U, M8 n
  crt num-cars
, e" k% V* u0 ~  C* ?" e  [3 t0 A2 Y) |) [% t2 C' q6 p
    setup-cars* r3 r  u9 C% X' n
    set-car-color
) ^* y% e" l0 C4 O% `. @3 e* l    record-data' m6 I- v/ k' p: Y
  ]) V4 Q9 v3 k4 c' n: I

2 y4 \4 m* E9 Y  ;; give the turtles an initial speed! z# U' s0 o6 B0 T, @, l) ?
  ask turtles [ set-car-speed ]
0 y6 \* s) k$ ]7 `1 Y4 s% l
1 f& m9 Y% P+ J2 ~( h! F, i  reset-ticks3 ^' {: K! i0 H' U0 p6 E3 b% A4 A: v
end" H; c1 s8 _+ N. j- q4 Z

) z. m; c9 m4 t- V: @;; Initialize the global variables to appropriate values
: n( J2 C( }0 v# pto setup-globals4 E% @/ O: n; d" q
  set current-light nobody ;; just for now, since there are no lights yet; W9 a, p$ j# ?5 a/ S: J' r, e
  set phase 0
5 g& y1 W6 c1 Z7 `  y+ }5 r5 W  set num-cars-stopped 0
% u6 y6 `: k( X1 D+ X" b$ u  set grid-x-inc world-width / grid-size-x4 O# _: f2 ?9 }
  set grid-y-inc world-height / grid-size-y
9 k) b! [8 W% R: @6 h! m
. [! w" R; x- b! C* Q4 A+ V  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary8 g# v) [1 L; j' y* v
  set acceleration 0.0992 W, e6 J" l0 C. C' j9 o
end
/ m/ b2 S& M! E# p) F0 h% O3 }& Y
+ b9 X6 j* R5 n; E1 k;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 z2 b6 c4 ^' m) l
;; and initialize the traffic lights to one setting
( V* F  L: B8 x& s! {to setup-patches% i/ K5 f" D/ g! }0 e( u
  ;; initialize the patch-owned variables and color the patches to a base-color
$ p' F  a" r5 E  ask patches9 g2 r. N' i) o( y, s
  [
, r! q* R7 a& Y( C    set intersection? false
; g: A# E+ O6 D, [1 D    set auto? false4 d# E: E8 d7 P9 e# ^
    set green-light-up? true  J( P6 I% l( x6 r
    set my-row -14 X  b: q, d( N9 n! [6 F
    set my-column -1
0 j. i0 {8 o7 |5 X    set my-phase -1
7 ?6 m; W! w+ i* i9 P  ]    set pcolor brown + 32 c! r( \/ F9 z) V. x
  ]2 y9 ^- Y: a& A+ z6 @" S$ [/ b" L
, l8 V1 P+ f7 [7 H2 v# O
  ;; initialize the global variables that hold patch agentsets  `& D" e, d0 q  Q
  set roads patches with
2 D  k+ H- j8 C: R6 }    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or* k4 A& q0 L% |, X3 p' n
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
  Q+ w. L, g& l  set intersections roads with
9 @5 a. _7 y' [0 Y5 T* t. B0 \    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
8 Q6 ~2 F; L0 y    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" ?# r1 a, o, b' u! D

% b# ?0 z( Y& ^0 A  ask roads [ set pcolor white ]( |* f$ x* L$ s# [) d3 D
    setup-intersections
! @% I5 b3 G" |; Q0 q" X9 Iend
' L. Z  j: r3 [" ^其中定义道路的句子,如下所示,是什么意思啊?
4 e# u# \( E1 ^) ~: k7 z1 {8 R set roads patches with
, D0 ^" m' |8 R+ p    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 F" q% f0 o+ f$ F9 L6 w( l
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 k1 u- @  Y2 @! q1 ~+ C0 x7 E
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, 2025-11-21 20:52 , Processed in 0.019072 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