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: 12299|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。
* k  B. @  V: snetlogo自带的social science--traffic grid这一例子当中,
. y- P' o% p+ {globals
# c7 y& q# g( V5 @# o, Y: E# @[3 ^$ R  Z' J; g$ D. q0 S7 n
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
* x% ^  x  B4 T/ [  grid-y-inc               ;; the amount of patches in between two roads in the y direction
: l* _* i: j$ y' X+ y+ |  acceleration             ;; the constant that controls how much a car speeds up or slows down by if1 [$ F3 F, E& O" N3 u/ e
                           ;; it is to accelerate or decelerate
# P0 N. J% R- K, u7 g3 s  phase                    ;; keeps track of the phase
/ Y2 G; ?$ {4 g: m! E" \  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure7 P# g% u+ ?7 |; D
  current-light            ;; the currently selected light  T* R5 P; h, P: k, S5 m

9 f  n* ^5 g: Z  ;; patch agentsets
  ]2 b9 o6 a8 E  intersections ;; agentset containing the patches that are intersections! a# ^  S. e- v; A/ ~6 V4 p
  roads         ;; agentset containing the patches that are roads
% [5 @$ r; P# X2 H]1 f. e  d0 i7 |
/ j$ E" A# ^' P7 J! N4 F$ _5 C
turtles-own
- P- q8 n# \2 N3 ?) d3 W[
. ^3 L0 S1 u- u5 g9 v  speed     ;; the speed of the turtle
. D) [3 A8 T% P; |* R# b5 G: {  up-car?   ;; true if the turtle moves downwards and false if it moves to the right- G: Z- x5 D4 J
  wait-time ;; the amount of time since the last time a turtle has moved
* L# ^1 x- D0 _; S]
2 G) q" R9 M3 N/ P! V4 `0 y" i8 h$ [# J
patches-own
  c0 Q# r" p* P[5 W9 c3 |9 X5 C& n) n- C
  intersection?   ;; true if the patch is at the intersection of two roads! ^& ^" c' ~# i# P( V: J4 B9 t
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.# G) W7 e, V6 D' g) z  u
                  ;; false for a non-intersection patches.  r! V+ L' O% f# q( E
  my-row          ;; the row of the intersection counting from the upper left corner of the
$ D) P6 m6 g6 o' i                  ;; world.  -1 for non-intersection patches.
. @0 j" F9 v8 R* t9 k& Q3 Y  my-column       ;; the column of the intersection counting from the upper left corner of the+ m, y* H- |1 A& f; X, O- f* |8 e
                  ;; world.  -1 for non-intersection patches.
' Y) x. j, m+ z* J0 \3 r& b" \  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
) N3 D: X) ]! K8 g2 O  auto?           ;; whether or not this intersection will switch automatically., n/ w1 q; \0 J/ i1 ]8 _  L
                  ;; false for non-intersection patches.6 t7 }' a: l& ~! Z
]- S' t9 b; I/ @# S% J2 `0 X
  z3 r2 r- i3 A( O( z& q+ `
. y  s$ z- G3 Q, ?0 F2 H  ~& Z% z
;;;;;;;;;;;;;;;;;;;;;;' f0 D# F  ~8 T0 R, M0 A2 [; B
;; Setup Procedures ;;/ c7 X$ Z% Y0 N" y* s3 U7 J4 {
;;;;;;;;;;;;;;;;;;;;;;
/ h& M* c; `* B1 v/ b7 [- z( @: z, a/ S; w
;; Initialize the display by giving the global and patch variables initial values.
+ {' Y9 [3 T5 x+ E" X* `% ^. v8 g' l;; Create num-cars of turtles if there are enough road patches for one turtle to
: \; w- H/ @. v" g/ p3 {. K;; be created per road patch. Set up the plots.
" J$ _( \5 U& a5 P% S$ M$ Eto setup
+ O# }& Q9 d3 b  ca/ q$ \3 S6 ^& Q: r7 {
  setup-globals
6 d9 a& G5 z! `9 h9 ?( i/ y
6 z* r& a9 v! Z# @/ \  ;; First we ask the patches to draw themselves and set up a few variables  w1 u# c  L0 O* n! V4 n' V
  setup-patches9 q! M* g  a* Z( v; f. B
  make-current one-of intersections
! |( R$ |4 b0 Z3 u. J: i( v  label-current4 ^5 t' I4 d& J% e6 G5 y  @% _
/ I' b3 m: v# _8 f. ^- q; g, A1 s
  set-default-shape turtles "car"- p9 {- Y, }7 N& ~

- J' v& }1 b* O7 {  if (num-cars > count roads)
; E2 C9 `) Q  {  [
( C' M8 O$ u/ ?+ ?    user-message (word "There are too many cars for the amount of "( \9 N0 d& X; Y4 }
                       "road.  Either increase the amount of roads "
- ~1 @7 }  |0 Q$ X                       "by increasing the GRID-SIZE-X or "
  v! `/ o' U; u; i+ p  [                       "GRID-SIZE-Y sliders, or decrease the "
; P3 j' P2 K. Z- Z' G                       "number of cars by lowering the NUMBER slider.\n". P5 f4 @1 A6 X' M, X
                       "The setup has stopped.")
/ z( B1 o# P  }    stop
8 k! g/ g. g! G  ], C' D* U8 v+ j! l) k, p7 a9 B
( M- S/ [3 j4 i' d/ f4 _" _
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
1 E1 N; x* o. i/ I  crt num-cars
1 q' p7 r7 Y3 x4 g/ ?. u( W  [& i+ Q( ?- _- Q/ l& m
    setup-cars
" R( A. d! s: M: j1 Q    set-car-color
9 O# f2 L# }" S! B  Z    record-data
  R6 T* n4 h4 Q! T. J  ]6 c( d% c- x- X0 s2 N

/ q* D1 J# `8 |2 \7 y8 _  ;; give the turtles an initial speed6 P2 R" \$ g6 d7 f. _
  ask turtles [ set-car-speed ]$ a1 y: [+ p: z5 H( W

5 i* z: K7 n% K* D! M  reset-ticks7 y) {0 w3 L! A5 D0 J
end, p" a/ j" y' \  t# g
7 [+ j% ]0 {9 R9 n8 R
;; Initialize the global variables to appropriate values6 ^' l, @/ c& b. H; a
to setup-globals8 T+ G8 E0 n5 o* r2 D7 h
  set current-light nobody ;; just for now, since there are no lights yet
5 S% W0 G& P) S; N4 N  set phase 0( n  i* F) d0 @  y
  set num-cars-stopped 0
3 i' j7 Q5 H+ B; G# H9 M7 q  set grid-x-inc world-width / grid-size-x
4 R; a2 j7 \( Q( V  set grid-y-inc world-height / grid-size-y# T% I6 `3 i! k# `1 D) U$ Z
: ?( z$ }/ W( e& D+ b) j
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary. O  [9 _0 e% q% u
  set acceleration 0.099
% C$ L7 p8 U  d# Y4 K. E9 xend- U. H, J5 B3 a: l; N8 b
- h0 y6 n; Z5 w/ ]2 f* G7 f# s7 |
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
+ u/ R, z0 Q# R;; and initialize the traffic lights to one setting3 G9 s; b0 m% _+ j
to setup-patches& c) T1 k: s4 i/ T6 N
  ;; initialize the patch-owned variables and color the patches to a base-color
$ g' L2 n+ M; d( y  ask patches7 u: H' q, p4 q- s6 r. Z
  [0 i3 ]3 f! U) n! M1 Q' N; s
    set intersection? false
$ s, ]% n7 ~1 t) W- t. I    set auto? false
4 f$ W* i% j! A& }7 b5 j% b" n    set green-light-up? true0 l0 K. _2 q% I" q
    set my-row -1  k! S* P0 ?0 s
    set my-column -1
' P( D9 E/ m7 x/ v5 p* A" d    set my-phase -1/ w* M- b- d! N) M9 e& ~7 p' j$ T
    set pcolor brown + 3/ ~- [; N# X. w9 Q  E' ?+ J
  ]) m2 f5 `7 K# y( E1 b$ L) w
8 |# ~' i6 k- M& ~& \
  ;; initialize the global variables that hold patch agentsets; v3 T6 K7 t+ i7 z7 Y
  set roads patches with
' z8 M5 \/ T; T: K    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or9 n3 S' |6 ^1 O1 H" q- W2 @
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 p5 u' K2 E* f2 t8 W
  set intersections roads with9 T0 p. D- T, }' b1 t# {: X5 F
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
( ^( d. V9 ^$ i# V    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; o: j$ @/ T4 X3 o. S0 `
) S! j5 Y$ g7 f9 u3 ^  ask roads [ set pcolor white ]) l  \1 c$ ^- A' O+ J3 W, f
    setup-intersections+ c! g6 ]9 b5 @; b
end* v3 e, [% T. p2 A& f( k9 z
其中定义道路的句子,如下所示,是什么意思啊?' p+ o; d7 \: @8 V3 j
set roads patches with/ p( N( B% C. B7 x
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
' p% m0 D5 C- d    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 F* L! i0 B1 V' Z& c* l- d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, 2026-9-15 12:17 , Processed in 0.016264 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