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: 8620|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。
' q) S- H6 M5 v+ T+ [: ^" Wnetlogo自带的social science--traffic grid这一例子当中,9 r* X( T" q; P! @% B
globals: ^+ F  L3 B, Y1 w& e1 P
[
: r* l5 x0 q7 C# ^. k  [. I; J$ D  grid-x-inc               ;; the amount of patches in between two roads in the x direction
$ ~# L! d; t; C+ K  j1 L  grid-y-inc               ;; the amount of patches in between two roads in the y direction: I+ a8 w6 F/ G1 {
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if' R3 n9 E+ _& ^3 c; I2 B
                           ;; it is to accelerate or decelerate
3 ?' B9 y0 ]. j8 ]. j- D5 m  phase                    ;; keeps track of the phase
+ D) w6 ]6 @8 Q  l$ @. N2 p  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure+ l* r' T+ j# R; b
  current-light            ;; the currently selected light
- f# ]4 B" G; ~# Y7 ?1 p" f# D9 L- s2 S  L( I$ O7 A  |
  ;; patch agentsets& H6 o! g+ o' H; {6 O6 E) G
  intersections ;; agentset containing the patches that are intersections# G% L( E4 u0 k1 F
  roads         ;; agentset containing the patches that are roads) S2 z% S9 w' E, X3 \& ~" Z6 j
]
! q% g: N0 I" ~. X& F  _9 f' A3 I' `  W* ~: Z3 n
turtles-own4 |! q+ ~! \: [; g% e
[& t* `0 Y6 Y$ P3 [+ B, A' F, ]
  speed     ;; the speed of the turtle
$ S9 V& t( g+ [# l. u) W  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
! q' T2 Q, F/ S' g5 k  wait-time ;; the amount of time since the last time a turtle has moved/ W2 f8 S" O  y
]
0 N0 w  ^8 X3 ^7 C! n1 X/ J5 P9 l0 q7 V, A$ e3 j: Z
patches-own
) c. ~: H5 ^8 @# D8 B. Z[
& L6 N8 N, n6 L2 N* ~/ ^  M+ S  intersection?   ;; true if the patch is at the intersection of two roads
! \8 g! D+ W$ c. R! [  z' ~  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
: S7 N" k' w( g- d5 s5 B! b                  ;; false for a non-intersection patches.
; p& J; R- L) F. o, p2 Y  my-row          ;; the row of the intersection counting from the upper left corner of the& [/ Q' d/ A* W3 `( T/ E( D
                  ;; world.  -1 for non-intersection patches.0 @% U: _  h6 `5 J4 Y  I" U
  my-column       ;; the column of the intersection counting from the upper left corner of the* l4 K: x1 `2 Y# ~; [8 G* I- W
                  ;; world.  -1 for non-intersection patches.
& w' i" A) Y3 y7 l& N0 E$ a  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
& k/ ^% U! N9 L' i  auto?           ;; whether or not this intersection will switch automatically.& y% J/ ?+ l( q* p# M
                  ;; false for non-intersection patches.- P1 |! W+ U5 E3 J# ]
]
  f- V0 P! L2 a' Y  I
' H* F- x7 G% J) H3 Y) r1 z3 c' _+ v6 f* a
;;;;;;;;;;;;;;;;;;;;;;: h# D8 L/ S( k' X: @' ~
;; Setup Procedures ;;1 a+ F! P# C( ]* ]5 ~9 c: n7 r
;;;;;;;;;;;;;;;;;;;;;;
* m) B+ a! @8 c$ a; b
8 ]) I; b  A* q/ E/ i/ V8 {! s' E;; Initialize the display by giving the global and patch variables initial values." r5 K/ D" ?2 {9 ]
;; Create num-cars of turtles if there are enough road patches for one turtle to* z+ o) Y9 V6 ]* ?
;; be created per road patch. Set up the plots.
0 p* g  ?* o/ m- n% c! jto setup
3 U/ q3 \! d- V+ m/ n  ca
1 q' K; r' @; V9 X  setup-globals
7 c% A, K  ~: F: e5 N6 k6 d+ ~5 u4 s: ?# Z" W
  ;; First we ask the patches to draw themselves and set up a few variables
% c( y/ {9 g5 l' p: z  setup-patches7 @* I! x/ }2 C0 G2 _
  make-current one-of intersections
- D# J* D1 _) S! Q  label-current
. d" m3 l9 `6 b& d9 x8 @2 Q' {
. `8 U% n1 M. G$ {( s  set-default-shape turtles "car". s! _- }2 a0 n( R: u

2 {: b: g  |" _) \  if (num-cars > count roads)# Z( v" j6 Q/ s2 r: J3 T  c1 C
  [% G. Y  y" s+ A1 g
    user-message (word "There are too many cars for the amount of "
5 ?: [3 C9 X) R% S9 Z; {5 F5 Y                       "road.  Either increase the amount of roads "
, V! V% z: g9 p/ G& S) l# Y! y# r                       "by increasing the GRID-SIZE-X or "5 r) v+ C: `) v- r+ q2 p# ]( l! b
                       "GRID-SIZE-Y sliders, or decrease the "4 Y7 P& K. {8 K1 r- d% f
                       "number of cars by lowering the NUMBER slider.\n"! R  p0 y; l9 K3 I: @) z
                       "The setup has stopped.")/ ?5 H5 U3 m' s% Z3 S$ v+ m- J
    stop" M  V- K: c8 e" `6 _  b; ^/ g
  ]$ D" I1 w; B0 y; h6 W* y
% m+ _9 H: V4 E, ~
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 k# q4 L' k3 a8 D8 U% ~  crt num-cars
" z4 f' `3 ^. D- U) H$ _9 D% @% q, g/ {  [
& b# B7 m/ O' K- n9 A  |4 k: c    setup-cars
/ H' d! H( Y& B0 K3 N    set-car-color
8 O) r& |/ r3 x# R7 z$ ]    record-data
2 b  |6 x, y! ?8 J) R3 p/ C8 P  ]
. l" [, @# J0 M8 F
5 @# G* b2 I. a' r8 [/ e7 I  ;; give the turtles an initial speed# R4 V% K# x8 L  _: [) O
  ask turtles [ set-car-speed ]  }9 N" K1 U/ W

" t* e- a/ U% X: w* Q7 Z0 N/ i, o  reset-ticks
  I5 B! a- A8 q) \3 E0 Z7 q' X" b0 _end
) A0 n) X1 V7 _9 i9 a
# S0 x: i. Q8 v;; Initialize the global variables to appropriate values
4 ]0 a2 o- t/ J' U7 Eto setup-globals# I7 Q- d3 h- o+ X% M  s
  set current-light nobody ;; just for now, since there are no lights yet! e7 L7 ?9 M( x! H! J
  set phase 0
# f4 \& Q) C' [' o. G5 y  set num-cars-stopped 0# Z- f- v+ u0 ?- w8 [/ H2 r
  set grid-x-inc world-width / grid-size-x
0 S4 }: H7 \0 C$ Y  set grid-y-inc world-height / grid-size-y3 q, E0 h9 W& l- m
. Z& c' W5 a/ u" A; O
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
; {2 O- {1 E1 V3 S0 ~  set acceleration 0.099
" j0 X9 \! _0 _, ?/ fend6 F& Y- M' X4 P% U0 L
; e. G1 f6 [" q/ z0 F0 E
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) a, P) a; Q6 d
;; and initialize the traffic lights to one setting8 F6 _6 R0 p/ T& L6 e5 P0 ]$ q
to setup-patches* r5 o' x: t5 O3 ~( B
  ;; initialize the patch-owned variables and color the patches to a base-color# m3 {0 f! V+ X& Q4 X- I# w
  ask patches& j9 E, O& P- O- ]% e& C1 x
  [) M( A0 o0 ~0 X
    set intersection? false2 e' D6 h: B0 `- p* M
    set auto? false
# i8 H* s' M5 ^5 q' i" _* k- U    set green-light-up? true
4 G, m2 y! Y7 F- @- k    set my-row -1
; b$ X# q* Q* T4 _    set my-column -1* h3 _! W4 `. [! O/ J3 |; B
    set my-phase -1' j% g* Q, _- y
    set pcolor brown + 3
3 l6 @6 N% S2 i% u# I  ]$ t$ H& F3 U% q# H

* |( n2 i# Q. c. w/ s+ a1 X' ]2 i+ U  ;; initialize the global variables that hold patch agentsets" K+ T' i6 R4 ~7 p5 J  {
  set roads patches with
/ L* C, e# B% c0 m6 H" T9 [    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, v5 p$ B$ m) q    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. j3 o. u1 a/ ]
  set intersections roads with
6 r+ t1 m/ a3 [* b% u; n    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
- C0 j9 w5 h1 g& l    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 {9 i* u" B7 t+ I/ x
* D0 ]9 k$ i" r9 H' r! [- v
  ask roads [ set pcolor white ]% f, @) k& h! p. u
    setup-intersections; Z7 W+ _, P5 g/ `+ ^9 u
end- o% R+ E3 n/ R- e. H$ E
其中定义道路的句子,如下所示,是什么意思啊?0 q6 }& T4 n6 W# h" m$ G" E: f
set roads patches with9 b# E+ L' h7 c- Z4 C7 F: E
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 m5 C; C" Y3 r% J: `% `    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; a$ K( h. b' _" k# `3 n
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, 2026-2-28 11:50 , Processed in 0.018136 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