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: 7268|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。
# }/ e$ V5 J7 F7 dnetlogo自带的social science--traffic grid这一例子当中,; O' y; W+ ^* e8 O5 U; k
globals2 J' d/ a2 x. i/ v
[
4 v/ w- z8 l7 h* q  q  grid-x-inc               ;; the amount of patches in between two roads in the x direction
+ K1 |/ W, `. L  grid-y-inc               ;; the amount of patches in between two roads in the y direction/ z4 @6 `7 x" T2 d$ Z
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
$ ~2 \3 Y0 X- {5 `7 D1 O  }8 L! A, g                           ;; it is to accelerate or decelerate, r" Q9 T9 h6 l7 k/ W0 t* b$ G# U
  phase                    ;; keeps track of the phase( Y2 b! B  Z- u9 m
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure$ }# M4 m. [  L" q# F4 i) {# p
  current-light            ;; the currently selected light
( S( W2 Y1 r: K& }; l5 [& c! b  `! x+ {/ y# e# Y
  ;; patch agentsets
* v3 M  U0 M) y* X' _  intersections ;; agentset containing the patches that are intersections. T) ~% D: q: ^/ y5 x/ Z% W
  roads         ;; agentset containing the patches that are roads
: t9 H" @" i1 k  [5 E$ \" @8 a9 i]
: ~2 b, b" S5 K
" A2 w' C! H7 A: Hturtles-own
: t3 h) P2 G% p  ]: e[# ?! W% P4 t8 @5 V5 Y5 [1 K
  speed     ;; the speed of the turtle
7 A: S7 r: `5 R" p  up-car?   ;; true if the turtle moves downwards and false if it moves to the right  q* R% r3 T1 c- }& h" j4 e
  wait-time ;; the amount of time since the last time a turtle has moved- q: {" j4 p' u6 G! t
]
) z# U" N" f) v. w6 U8 \+ w+ J; F4 K1 Z+ `
patches-own' {8 B6 E4 C  D2 A9 U7 p
[
9 N( h$ z  a8 w) t/ ^% {1 Q  intersection?   ;; true if the patch is at the intersection of two roads
% r$ E. D6 Y1 m/ A3 }" @, J- ?  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
, J+ m# l( S" b; E                  ;; false for a non-intersection patches.% K! ?1 G/ ?) C: X) O0 K% m1 `
  my-row          ;; the row of the intersection counting from the upper left corner of the
, q. s; y' d" f3 C) K                  ;; world.  -1 for non-intersection patches.
6 I  I' g( F8 {' K; h5 k! \" y0 f  my-column       ;; the column of the intersection counting from the upper left corner of the2 P* L* r' p! x0 A# _8 U1 C7 x1 E: {
                  ;; world.  -1 for non-intersection patches.3 O. i  c. n& G; ?
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
' G" ]( `7 _7 G  auto?           ;; whether or not this intersection will switch automatically.1 J% O$ l# g& X7 x7 [! p' K; X' {* T
                  ;; false for non-intersection patches.
* x- y+ G3 K9 k4 }, l( C5 |]/ F, O* I6 z8 g4 w) ?# ~6 E

' N4 N" M0 a) l. q0 u4 E4 |% W/ Z. N* Q" N# ~" }  n
;;;;;;;;;;;;;;;;;;;;;;! Q7 _4 \( m% a$ y5 {3 m. \5 e( ^
;; Setup Procedures ;;
8 P; X7 M7 A% E/ F* U  D;;;;;;;;;;;;;;;;;;;;;;3 N/ v" v$ ]" ]- V

+ j; e" d# y: Q7 u& n;; Initialize the display by giving the global and patch variables initial values.
' e% O) q. k# X; p. \% p;; Create num-cars of turtles if there are enough road patches for one turtle to
8 t9 e8 p5 |) q9 U- A;; be created per road patch. Set up the plots.9 _* }% n! R  \: ]; j$ U
to setup
# B: R' F1 l3 l& q. i8 d- q  ca7 j6 H+ w* ^6 S$ M
  setup-globals
5 ?9 \" a" i4 r& r- O
) @( k! F! g# k% s/ V2 v- L  ;; First we ask the patches to draw themselves and set up a few variables
6 I5 f5 F% ~/ l6 p& u/ P" ^( {  setup-patches
: W; x! q! H8 C$ t' B  make-current one-of intersections+ d2 s4 ?( [. c0 H$ S. [
  label-current! x( E+ N8 r+ r* G) s+ I) T
; w. Y: ~; c" b* t. [( O; i
  set-default-shape turtles "car"6 ^3 Q; Y. C# D+ x" \- {& E1 C
* r  J. A# x, u# q1 o: k
  if (num-cars > count roads)
3 A! O7 u# e; `* s: v  }  [6 c7 d5 {; A. `% R, u
    user-message (word "There are too many cars for the amount of "
/ r2 z3 R4 ?' P                       "road.  Either increase the amount of roads "% f9 k  P# q$ S% F# j* M. `1 m: \
                       "by increasing the GRID-SIZE-X or "
( H+ d$ I; K1 t1 I$ y( m: b* n5 m                       "GRID-SIZE-Y sliders, or decrease the "
" ]2 F( A9 j7 U1 Y. m                       "number of cars by lowering the NUMBER slider.\n"
5 \) u; O' m4 z! M5 E8 N$ y! F2 W                       "The setup has stopped.")
5 y1 `/ X+ B: m7 u9 e    stop
7 {4 }5 n2 _. ^1 R6 f. U  ]
( e: k# C7 p2 Y2 t: A0 s1 v! e0 |% r5 E! X+ p2 H
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color" D, Z2 _  Z7 w* X  w
  crt num-cars: r( \; e: j! R' W% {  X
  [2 ^* I# G0 H& p2 S% ^3 V
    setup-cars- H7 d7 e- F  g$ B' t- n. U- g3 E
    set-car-color0 }. K6 w: z) v$ s6 H+ p
    record-data/ Z5 S1 p& @+ u
  ]
8 S: c7 ^8 o" q1 e& S. n+ i. `
' ~* J+ A! ~1 V! G2 O  ;; give the turtles an initial speed
3 `0 o$ _! `8 I& W: A$ \  ask turtles [ set-car-speed ]
# a& a# g2 b/ z0 i. p
. z, A  s, k0 Q  reset-ticks& E3 P& X3 ]' l; H) |, A& K
end  ~; y6 P/ Q0 [, \. n" z

/ C/ Z6 ?/ C& w4 V0 k/ ]% H;; Initialize the global variables to appropriate values
; j6 \( V! g3 m! S7 }3 Q3 R4 _: sto setup-globals
* m/ w2 @% X6 b* j  set current-light nobody ;; just for now, since there are no lights yet
" }5 v, ~9 G- s2 K  set phase 0/ ]: L9 i- Z6 B6 a
  set num-cars-stopped 0# o; V7 F# ?8 X$ {  _4 {
  set grid-x-inc world-width / grid-size-x
4 y4 O$ v+ G$ T/ s( e6 O  set grid-y-inc world-height / grid-size-y7 K+ r& A) J' i$ V! Y/ D

, d4 u  e2 j# }' B% h  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: J- |2 O$ [: @* g* W
  set acceleration 0.099" a8 C% G, U3 P, s' W& a! M9 F
end
# f# P. i$ e$ t3 D( O! `; v) ^9 D% }- L! [+ p7 e
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
; y% R! T) y8 e' [) o* a# e;; and initialize the traffic lights to one setting8 L4 M* R% x: W, H, q
to setup-patches
; T6 B# \$ h8 C  ;; initialize the patch-owned variables and color the patches to a base-color
; r' k  Z8 Z% E6 p9 V  ask patches: G. Q/ p0 p' C3 D& r7 B+ N1 b
  [
) c' p. w3 J0 N! X- m$ e8 _8 a    set intersection? false6 \* n( ^# w: _  N5 ?- _3 G
    set auto? false6 ^. K# T  _# W8 e* M
    set green-light-up? true
* l# p/ i, W8 Q' p' ]" a! y8 ]    set my-row -1
: \3 W; y6 Q) a5 H7 D; g    set my-column -11 G8 }0 q% d: o! h9 S
    set my-phase -1$ @) h9 Q: |! m# L8 y8 `0 v6 ~: F. x
    set pcolor brown + 3  s2 X  M6 L8 t# ^. P" y
  ]8 x( b. j0 o' b. P5 L: P7 ?

. l! m* c  t3 l+ L$ N/ E  ;; initialize the global variables that hold patch agentsets% H0 s: o6 ~1 z) q! \
  set roads patches with9 a$ M, _, y2 u1 F
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, ^3 S7 q4 a2 G! F- f: P( Q
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 ~* L. v( a. F( f
  set intersections roads with
2 x6 D# T- K' l3 n0 M# [4 [    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
( D. n0 k) W; c' ^    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 T% y6 J) h3 Z# f* T/ W7 D8 m
1 g" b# v$ x$ O; q' M: [. P; C
  ask roads [ set pcolor white ]
+ `/ c& N) U! }+ X$ Y    setup-intersections
" e$ G- I9 f9 r2 D* F2 uend) \6 o! j4 W- a9 x4 B1 _; Z# r1 C
其中定义道路的句子,如下所示,是什么意思啊?9 a! {5 e9 W" b( M: Y/ U
set roads patches with
- E# m+ j" _9 Y+ A* y/ l    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
; r3 m, V* d# `- g! T" J    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 w/ N& g7 U& o, @( 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, 2025-12-3 20:20 , Processed in 0.024294 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