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: 11993|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。
! g2 g" x0 |( t5 @; Q" Qnetlogo自带的social science--traffic grid这一例子当中,. v! w( Y  v+ q6 t" t+ E2 q5 G& p
globals7 {' g7 [  L# k$ |; q' {) I
[: E8 [. l8 C. ~5 Q  o5 p
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
1 V$ @2 ?6 o6 R5 P; x$ d  grid-y-inc               ;; the amount of patches in between two roads in the y direction
1 C1 f+ ?. I4 T# @  acceleration             ;; the constant that controls how much a car speeds up or slows down by if5 T4 M1 w2 d* n' i6 F. O) v
                           ;; it is to accelerate or decelerate2 c& y$ R8 m8 \/ [7 l. C
  phase                    ;; keeps track of the phase  O# M2 k* P- M; ~( C7 e
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure8 P& H# t6 e# v- ^1 z1 C
  current-light            ;; the currently selected light9 Z6 A. t  a% ?3 B
4 F# |$ r3 P) ^/ ]6 y! a; `
  ;; patch agentsets
: m) C, Z! l8 a3 i! w" A& _  intersections ;; agentset containing the patches that are intersections
. f3 Z2 M: f; r* y% d  roads         ;; agentset containing the patches that are roads
8 C+ \' B' f, b( L]
* X  D/ B6 E. _' ^' K, a" f" `$ y* @0 L
turtles-own
2 Q4 m8 w% c' t, L[
+ ?4 m, J: K& u: T+ k  speed     ;; the speed of the turtle# y# p& ~5 ~1 Q- b- T3 O. \
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right- D0 P' y2 A; N; K. w: N1 @  w  n
  wait-time ;; the amount of time since the last time a turtle has moved, l0 N% @. i2 U- z1 q2 {1 l
]' i) V5 i0 @! Z$ ]$ c
$ l: h  O  p0 H* U( W
patches-own$ @9 J4 ~6 B' y
[
8 d$ g  |* u3 r: y2 x0 v+ X, |  intersection?   ;; true if the patch is at the intersection of two roads
4 {6 x( j2 s' S8 y0 {  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.* {5 r7 |+ h8 U2 |" Q' Y: a
                  ;; false for a non-intersection patches.
* p' D5 |. Y8 N2 a5 c3 q# C  my-row          ;; the row of the intersection counting from the upper left corner of the/ W# o& B" c8 A. T5 q8 n1 P8 W2 E
                  ;; world.  -1 for non-intersection patches.% V# m( }% ~! \
  my-column       ;; the column of the intersection counting from the upper left corner of the, S7 M# X5 w- B; \4 x: F' U- D
                  ;; world.  -1 for non-intersection patches.# N4 t) s* o. A0 N9 J7 x
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
$ C4 k. w6 t, J$ c  auto?           ;; whether or not this intersection will switch automatically.
6 t' V! W/ }& L                  ;; false for non-intersection patches., E1 ]6 A$ T9 T  q( q$ z8 E" _
]
7 {* p7 r# c+ l2 Z; f! H+ g! P1 v! h$ @

5 c5 T2 Q7 b9 f1 ]) S;;;;;;;;;;;;;;;;;;;;;;  e7 ]3 B# s( D# e! f# x
;; Setup Procedures ;;& x- s- ?9 i# Z$ z3 V
;;;;;;;;;;;;;;;;;;;;;;1 l- o- l7 b2 ?* f; |( ?5 j
  h9 ?) q6 f  j9 m" d
;; Initialize the display by giving the global and patch variables initial values.9 a+ e. k/ n' r
;; Create num-cars of turtles if there are enough road patches for one turtle to
1 c. @+ d3 ^2 v' ?: x;; be created per road patch. Set up the plots.
0 Z. w& f+ ]  y! zto setup
. r/ d6 c. `0 z1 K; }/ U  ca- N9 L3 Y# [6 \. ]' x! V7 B8 Z
  setup-globals
9 e" W# R( B" ?) l
6 S( W3 r& n  X) ]9 I  ;; First we ask the patches to draw themselves and set up a few variables
& ~( E$ M2 B5 v+ b( e  setup-patches7 f# G! A& r4 Y- P1 P2 ?1 q
  make-current one-of intersections* J/ p% r  b6 L9 m/ C$ i
  label-current/ R/ l2 @% k  `$ F

. ], z: Y  V1 G. e  set-default-shape turtles "car"
% e5 k. c: x7 u( R/ v
, a0 g; j; O0 a5 C3 }- k  if (num-cars > count roads)
" t8 X/ G; A7 u+ C! T8 u) O4 Z  [
3 i; X6 z) A. |# Y    user-message (word "There are too many cars for the amount of "; c- F  x1 Z/ z3 |, M7 _& ~
                       "road.  Either increase the amount of roads "5 p" l" {2 v- b  @5 L, r
                       "by increasing the GRID-SIZE-X or "
0 W6 b3 _9 X5 l3 c' v9 r0 u0 e) K                       "GRID-SIZE-Y sliders, or decrease the "
0 W! R% n# G. F2 b  c# H% L+ t                       "number of cars by lowering the NUMBER slider.\n"
" D9 m9 c' f) F, T7 I                       "The setup has stopped.")
: b3 K* t5 G8 Z& b8 {& Q    stop# {1 n, |  d5 c4 V" R0 l# |$ S
  ]
# V" m5 Y1 o) c' a' E& n, u+ k( r8 a/ S
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color# a9 i1 i7 `3 Z$ D6 h0 o7 F
  crt num-cars
; z8 J- l0 Q- M6 ^  [8 v2 C/ g& R- |& i8 ]
    setup-cars& F" a8 t, F7 [) U* S2 N) W9 U8 x
    set-car-color% t) V+ n+ a) F
    record-data
% w6 K/ |$ H$ d. J! @) V# B  ]# Z2 |! u. y& Z, X# D# e
3 P# I; U" g! ]: Z
  ;; give the turtles an initial speed
. O/ u( x, W4 |( a9 E" m7 a  E. u  ask turtles [ set-car-speed ]6 j# e6 x, y3 h# m
1 G% p, W2 b5 A
  reset-ticks
. I/ T7 Q& t4 r6 ?# s7 zend" L) b: H) G5 _! @- [, n$ z

# [* ^$ G5 k" H8 ~9 [;; Initialize the global variables to appropriate values! @  X- }* l( x- |
to setup-globals  d3 `  A) R) h) x* q
  set current-light nobody ;; just for now, since there are no lights yet7 H7 O/ x+ E0 z4 X
  set phase 0# B8 Z: Q, {' b
  set num-cars-stopped 09 g. H3 }4 N; ~9 l- p
  set grid-x-inc world-width / grid-size-x4 o& [! U5 V# R( F
  set grid-y-inc world-height / grid-size-y
! K9 Z3 T9 ~  a1 x$ M2 p0 i
3 d0 a# P4 X$ a2 C5 X  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
2 K2 i2 {. o. }  set acceleration 0.099* U/ y% q7 \( H& B' P8 J
end4 D8 \0 |) ~- L! ~/ J
7 t$ N6 ]: n0 m5 N' b
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,+ S6 B) D0 N5 V0 N
;; and initialize the traffic lights to one setting/ f1 G, {1 S) X
to setup-patches7 F0 {8 A: N% X0 p: [( [
  ;; initialize the patch-owned variables and color the patches to a base-color8 j( Z: k4 v* R3 T0 {$ K! o
  ask patches
2 V  c, E! c1 H# e  h  [
9 r/ i9 v2 l/ G) n    set intersection? false
8 h) r5 W+ X! [2 u4 A" r2 G    set auto? false
& K1 E4 ], h/ I4 d5 G( m    set green-light-up? true9 z# `3 N- M* N: r
    set my-row -1
' {' A. C( Z" _- h2 z6 m3 T    set my-column -1
" B( C; B/ S! U; k9 E) t- ]    set my-phase -1# Z1 R( t1 N; [! x, M- \7 _# c
    set pcolor brown + 3
: j: i9 S* i' D& m  ]
' ]8 z" J7 m2 z! ^5 y9 q3 Z9 \4 C7 Q1 [3 q
  ;; initialize the global variables that hold patch agentsets
" i9 V6 c. P) l% K; o  S( M/ ~  set roads patches with; z& A7 c+ v2 H8 Y/ }6 c# ?' Z1 v
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 [2 B' f7 N6 m& e1 a0 Q  f- k5 i
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- y' T% c5 t: D1 N  set intersections roads with
  J- G2 j7 S# s- l" R2 B    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and$ ~: G( `7 c: X2 |% c
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" Z& i6 t9 d% s2 ?* m$ K
- ?% H! g* o+ t& R$ Z; R; B" L  ask roads [ set pcolor white ]
9 W& _. u% A) v+ Q4 n    setup-intersections# I8 E& R$ u% _/ L: q/ T$ H
end  u4 e0 R4 R( h, @7 |
其中定义道路的句子,如下所示,是什么意思啊?
5 |1 P) Z6 C/ b. Y0 m& X4 y set roads patches with  y; p" u. e( f# l
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or  B/ j7 H! u% z/ C) l' y2 v& y" R
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- V3 b$ V5 Z% `# \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, 2026-8-28 21:18 , Processed in 0.016053 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