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: 8889|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。
. t$ ]  l  x1 nnetlogo自带的social science--traffic grid这一例子当中," K/ [& y+ A, \: a7 @- k2 P* y
globals
0 ~: H  D- c5 @3 b1 t' y! p4 v' p[: ?" \, ^, d0 L( a: Z# H% x
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
, ~$ A/ P% m5 C" U1 j  grid-y-inc               ;; the amount of patches in between two roads in the y direction& B0 q9 f3 P: y4 U% i/ H$ Z3 A
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if6 ?8 @2 a3 ]( P7 |& {! I5 W
                           ;; it is to accelerate or decelerate
9 c, C5 q0 V4 G2 \& [  phase                    ;; keeps track of the phase
1 g4 R0 k9 D. S& X! _$ G  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
5 c9 o/ \. F1 y  current-light            ;; the currently selected light; ^* O% n" q' d) {8 T
( J  g9 ?3 J) l; {
  ;; patch agentsets) Q4 b( O% d% n' w5 ^6 W
  intersections ;; agentset containing the patches that are intersections
3 ~2 F/ t' Q% O" r  roads         ;; agentset containing the patches that are roads
5 w$ q1 ~. t8 j( `8 s/ }]8 L4 z; p/ s3 Y7 y$ d5 z

6 c1 Y6 @& [2 Q0 f% D6 {  mturtles-own
" b* G9 A, Y. r0 z8 `[7 _8 m& c& }* p5 |" p
  speed     ;; the speed of the turtle
# N0 O$ ]" W' h( X4 n  up-car?   ;; true if the turtle moves downwards and false if it moves to the right3 M1 r9 E, W! Y! u( ?& ]" p
  wait-time ;; the amount of time since the last time a turtle has moved
% d& x, F0 z9 A) a9 ]4 Z) U, r]% b. l" S& i% u/ j- Q) }! L( A
# m3 N1 o) ~4 H6 G7 p$ a! ]
patches-own0 {2 g* Q  n! l
[& e' M4 l1 R0 X: z4 R5 g% U
  intersection?   ;; true if the patch is at the intersection of two roads$ L3 F+ O/ L5 t) `
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
% H: ]( i7 [& I( p$ I' m2 I                  ;; false for a non-intersection patches.6 d" I5 d# O% Z9 |/ b2 l* e: w
  my-row          ;; the row of the intersection counting from the upper left corner of the
* @) ^4 a' Q6 V7 a                  ;; world.  -1 for non-intersection patches.- W1 F" ?6 A) i$ u, l" o! h+ t
  my-column       ;; the column of the intersection counting from the upper left corner of the
, n: _/ k/ f7 t4 n! y                  ;; world.  -1 for non-intersection patches.
+ y7 H& x+ Z' @8 v9 Y* _; D  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
# ]! |4 o4 `' H  auto?           ;; whether or not this intersection will switch automatically., C  t$ ]9 M. E) ]
                  ;; false for non-intersection patches.$ [8 N: h! j0 A  s. b
]
: \4 o+ E! W9 v
' m! r# W1 B+ d; [; y
; k  c9 w/ |4 w9 d, N8 C# H;;;;;;;;;;;;;;;;;;;;;;4 q7 o: Q9 c9 m  I+ }+ j9 Y$ k2 D
;; Setup Procedures ;;7 ~& H6 q! [; w
;;;;;;;;;;;;;;;;;;;;;;  L0 ^  t) W, G. a. ~0 t& w8 e

- n  o5 G2 L# p- l) D. W: h8 J;; Initialize the display by giving the global and patch variables initial values." i& W5 F0 P* k+ k
;; Create num-cars of turtles if there are enough road patches for one turtle to
2 S) b7 t9 J9 V* Y; v) _5 ?% I* \6 @;; be created per road patch. Set up the plots.
& G% N5 F% {3 W1 d, Y1 c( h) z9 Z! Qto setup
( W+ z& @* x$ B  ca! l; c7 |; q# [- i) G. }
  setup-globals
, m9 e8 c! A) h  \; C7 Y1 S0 e0 N8 T6 P. f/ M% E
  ;; First we ask the patches to draw themselves and set up a few variables
+ f# _3 ^, _# P# y; ]& H2 l; z% d  setup-patches: b; ^" E9 _. E1 ]  O$ ]
  make-current one-of intersections! C5 k& o# I- F! z0 U9 G
  label-current
9 g, ?" q7 y; P# k! c, |: y$ u& g1 T7 f# Q) X: C( |4 G# _
  set-default-shape turtles "car"$ i/ L# t9 G* u! h' w' E: m
6 x% e; \! l1 n6 X
  if (num-cars > count roads)
0 X! {4 [$ M, o, S6 D6 N1 G  [8 p8 b, Y6 G" B3 Z, Y
    user-message (word "There are too many cars for the amount of "4 u% [0 u8 Q# r. n: a/ N3 c; U$ i
                       "road.  Either increase the amount of roads ". y  L1 ~5 y6 P1 G
                       "by increasing the GRID-SIZE-X or "
  n( W+ H0 a' D* t' F6 Q, Y                       "GRID-SIZE-Y sliders, or decrease the "5 c7 ]5 z! I, X: c/ C+ f
                       "number of cars by lowering the NUMBER slider.\n"
! |3 G4 y3 W6 G' u+ S* @# p  l                       "The setup has stopped.")
5 i  [) |" j* g2 Y7 x' w! l    stop5 T" F! _9 G- T1 u. g" Q8 ^
  ]
6 L! t# g# D- E! g/ y( R2 t5 I7 N* d6 j7 w. s& R- d
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
  l( Q$ I- j4 @' G3 ?- e- ^- P  crt num-cars$ N/ e" P6 L& ?
  [
: C8 q* u5 E4 ?* J3 J    setup-cars8 K" J; y7 E9 k+ G! D
    set-car-color7 d" o7 M4 G0 D$ ^: O
    record-data
/ q2 _. ?) |. M: Y  ]# {( P4 D! w, [5 }4 x$ o

6 [0 S1 P6 y; \0 ^" \# Q  ?3 }) E  ;; give the turtles an initial speed8 A! Y+ a" a4 Y
  ask turtles [ set-car-speed ]9 u  _/ j% p0 ~

& x3 `' D) A9 r  reset-ticks( W1 [" v1 T  [3 `, F$ n
end" n$ o- P" O7 ~

( m$ A9 V# a- f! x# Y;; Initialize the global variables to appropriate values: _& \& [; u& q
to setup-globals
9 K) W+ W4 H; G5 b1 d. E) Q  set current-light nobody ;; just for now, since there are no lights yet
% \+ l4 l# \7 ^* w  set phase 0& e7 @' i1 }: l) U
  set num-cars-stopped 01 ~- R, i1 w# M9 X
  set grid-x-inc world-width / grid-size-x
4 }8 e- X/ i" b0 W, B. ~9 J: [; E# Q  set grid-y-inc world-height / grid-size-y
  Y! H0 d; F0 _' [/ y. `* j! {- m# `' h; s7 _
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary* r( g7 w& L, [. S
  set acceleration 0.099
: k' E2 @! j' l: h* S8 o9 S$ Y) Yend
" h3 o  s: N8 ]  {. G, g7 A% P" \
. G8 j8 S2 e( b) D;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
$ S, @0 G" e9 i$ P) x% t;; and initialize the traffic lights to one setting9 ~4 ~1 R- G, J% j, t4 \0 M
to setup-patches
7 G: Z) z3 d8 \# m* h6 B  u  ;; initialize the patch-owned variables and color the patches to a base-color
" T6 y: l9 ~9 L3 u3 Y  ask patches. R9 k' l  {" I) j3 R9 ~: b
  [
8 o$ D+ O, f* q% {0 e- ^8 W6 d4 v    set intersection? false, X* K( L2 w& i7 I" b2 h0 p
    set auto? false# U/ \" }" \- }" B2 N
    set green-light-up? true7 o$ H; j1 P9 J, L% R8 Q) M
    set my-row -13 z5 C% Z; b8 e5 N! C; i
    set my-column -1! L; a6 _- }' v" H8 ]3 l
    set my-phase -1# P7 G/ D2 L  y- ^3 y% s
    set pcolor brown + 3
+ D4 `' J. ~+ F! e! e# I: C  ]
) w+ g$ z& T8 t& ?3 L
$ g# A- ^! }0 G* v4 d  ;; initialize the global variables that hold patch agentsets
: n& I6 F% o5 V; ?# _  set roads patches with
: Z1 I; ?; g2 q$ a    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, L8 t' j9 O6 g# W' E5 r2 M
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% R6 A! E* U+ m7 X
  set intersections roads with+ S. T" R+ Y. C, e2 `" [4 I6 N
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and4 x& H7 ?! \2 x7 w* `3 e- e
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 B# `" H6 @8 t. n7 j

9 H/ ?5 x0 q' i9 r! T- t; \  ask roads [ set pcolor white ]
  g- t6 W9 m! Z3 q9 e    setup-intersections
7 D6 b: a+ Q- {% K- s" o8 C5 Oend9 r; D! Y* j. i4 Y- i$ o
其中定义道路的句子,如下所示,是什么意思啊?
* _6 Z3 W1 S' x; _& a; z4 m set roads patches with
4 S. G4 n) n) R. B- f0 E    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* q- a+ X, Q; p1 W- x# N; q4 \% G$ v    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, c; ~: p4 M- o! J5 m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, 2026-3-14 05:20 , Processed in 0.014801 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