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: 11130|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( U( x7 N! o9 Z  T4 t
netlogo自带的social science--traffic grid这一例子当中,: o1 L. B+ m6 t
globals, s3 Q8 O* T0 J
[8 p, v6 B" ~" V7 [9 `
  grid-x-inc               ;; the amount of patches in between two roads in the x direction0 R5 h: b5 c( Q* s, k8 _; X7 y9 n
  grid-y-inc               ;; the amount of patches in between two roads in the y direction) C0 b- W/ o( T* \% k6 m: N  P
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if# s, U) e, S. l) O5 O! p/ y
                           ;; it is to accelerate or decelerate+ s1 ~0 m" P( Q6 J
  phase                    ;; keeps track of the phase
! [, {1 p# m' }1 J% w( n1 r4 W$ J" i2 c  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure5 Q5 g* u5 e! \
  current-light            ;; the currently selected light' V1 G2 p) P6 `# |, Q2 L
7 p* Y2 s+ X. ?6 j* \
  ;; patch agentsets/ `* f& i  c& i7 _
  intersections ;; agentset containing the patches that are intersections
/ W  A' t# [" M2 [, K4 ]+ V1 \5 o& L  roads         ;; agentset containing the patches that are roads
8 ^* [. z- P* p* u$ n]! A- Z" R- z( H
1 n. }' _3 l6 m' g; }! W
turtles-own
( \0 x  r0 B: m% K/ b8 s9 Z8 \[1 y  m  W& m. j. l4 u& c4 F4 l2 O
  speed     ;; the speed of the turtle3 @" |6 m; D* {6 M; G7 }- p/ x
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right! n' h* S  t! a) O4 }  W
  wait-time ;; the amount of time since the last time a turtle has moved
& m+ E% I3 X; J]# P& G# M& i6 ^, `
3 M' U# L5 [+ j% R! {6 r$ {! j
patches-own, N6 Y; C2 u, y  m" s. V
[
+ R& S' L" G2 }/ y& r  intersection?   ;; true if the patch is at the intersection of two roads
1 \" S' P/ d: v4 W% a: j/ A) G  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.6 i5 K: W0 j0 c! a( J
                  ;; false for a non-intersection patches.7 Q2 B  y! ^5 m/ y6 t5 F+ y
  my-row          ;; the row of the intersection counting from the upper left corner of the
0 i1 L) L' _9 k/ D' f5 b                  ;; world.  -1 for non-intersection patches.
) a1 V* x8 W- |. r1 T- L  my-column       ;; the column of the intersection counting from the upper left corner of the2 H/ ~% n& Q$ N% X) P7 ^: c' }, [
                  ;; world.  -1 for non-intersection patches.
- W; B) K  i, x8 l5 B3 U  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.% G" c7 z/ A$ e: E% C
  auto?           ;; whether or not this intersection will switch automatically.* k3 R& V( m/ v# G# o; D* o5 x
                  ;; false for non-intersection patches.
+ a8 o% u& P* k1 H" `) T3 @]  l, {4 ^! W, E1 z  L* B

  Y& B: ]' y) c! K: X8 Z
5 m, \3 ?5 E/ |7 M& F8 J6 F;;;;;;;;;;;;;;;;;;;;;;
7 V' g. t1 K# I% I7 Z! z;; Setup Procedures ;;0 A* z" B+ g; i4 K/ F5 O! {
;;;;;;;;;;;;;;;;;;;;;;
* X( n: s* ^. v
- N4 \/ M5 v2 E6 C;; Initialize the display by giving the global and patch variables initial values.
6 O" M0 O+ ~' Z;; Create num-cars of turtles if there are enough road patches for one turtle to
5 \% S0 o1 @6 K( b4 T& p9 D7 ^;; be created per road patch. Set up the plots.- ~! c' ?) |6 p! A, @  x, ^& q
to setup" X- o$ X" B$ l2 w) }* Z4 E  V8 y
  ca# Z) }4 H# j& x# V7 M  `
  setup-globals- B6 s* F$ @/ x% A3 W8 u

2 A4 j. o4 _- H2 k+ G* t2 r  ;; First we ask the patches to draw themselves and set up a few variables
2 k' @; a( v# h! D  setup-patches: ]: M5 N0 `# P, |  m" y. m4 l9 j% C
  make-current one-of intersections7 b' Q$ N0 y. P
  label-current
* I* h# e  W  ?9 d1 T; i, S! i8 e
  set-default-shape turtles "car"
: I  H8 X/ V% q  g, B! p
( v9 T. q' r( j4 P: ^' d* n! N  if (num-cars > count roads)' C* J/ x9 G8 u, F+ J% R; r* M
  [
, B, D3 j7 V+ i  e6 f: V# v    user-message (word "There are too many cars for the amount of "
8 E' _3 r( J# l1 w3 n( Y& c                       "road.  Either increase the amount of roads "5 ~6 S4 \* L6 Q% O
                       "by increasing the GRID-SIZE-X or "
5 F0 k; L7 L6 y                       "GRID-SIZE-Y sliders, or decrease the "3 V/ B" _  o& K7 Y
                       "number of cars by lowering the NUMBER slider.\n"
. z' G" F- R' l% g) ?" q                       "The setup has stopped."); r$ h3 M3 p: n/ {8 G! z$ q
    stop
6 n( {* d( G' \# j" y  ]# Y% N2 d! G7 P' y7 Z: Q
7 i6 D" C. b+ N
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color: r: h# ?+ I. `9 j# z
  crt num-cars4 \8 O2 ]; R, e& Z4 S, ]+ ~  V
  [
+ N* W$ i' I2 Q% F$ J3 q0 r+ F0 |6 h    setup-cars
! T! l. P9 b; {    set-car-color  a% v' J7 ^9 \9 \, ?( Z2 `+ l& c
    record-data% _! F' m. S+ y! a. b: A  N+ x9 X
  ]' _' _9 h, T9 R, ^7 [: k7 ?

9 r) q8 W5 z' }  ;; give the turtles an initial speed
# D5 q& p8 ]* U& }& E% y  ask turtles [ set-car-speed ]% S- x* ^1 y' k0 q

# y. a& v/ ~6 j4 w  ]  A3 `% @  reset-ticks7 r7 U* X+ A- a* }" o
end
- e2 w" e) g  C8 t$ R+ P8 @
: O5 I; R3 {; P+ }; s;; Initialize the global variables to appropriate values
& B- _2 H# h& d% w. rto setup-globals
, y. I# ^$ Z+ ]3 Y3 d+ {  set current-light nobody ;; just for now, since there are no lights yet
2 A8 r$ X) l5 u" T: J* N! t9 ]  set phase 0
( t3 ]  O  u# H" r3 K0 C( ~  set num-cars-stopped 0" S% R- Q1 d. X
  set grid-x-inc world-width / grid-size-x
/ ^- o0 g# [- l. D1 w5 n; s: v  set grid-y-inc world-height / grid-size-y
1 ?. v1 D2 {' K( I5 d9 ?6 f) B* K" K$ b7 R5 |( U" {/ V
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary  H. l* E, y8 F+ E) D' ]# L
  set acceleration 0.099
$ L) u. n/ k, Z; R" Lend8 Z$ @' C) M7 m; d# ^5 K* Y% u) y+ ?

; o+ I4 P- E2 M# f3 a* I( h: T( d;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
6 Z. d8 l9 `/ Z7 L;; and initialize the traffic lights to one setting
' y/ d5 A1 D; \1 ?6 Cto setup-patches8 A* d7 l5 ^  }' S2 T
  ;; initialize the patch-owned variables and color the patches to a base-color+ m" @9 w1 L  m. ^0 D" s
  ask patches+ v. E% A2 H7 D8 c0 p! j7 [! e' a0 I
  [% B  c* W9 l- ~; p7 r
    set intersection? false4 r! I$ s) U; ^8 L6 `9 Y& ^
    set auto? false
: ]5 K% |) ?/ o4 e: H    set green-light-up? true8 V" e1 u0 o) x8 D& W% z7 m
    set my-row -1
6 `4 @  ^/ O5 J4 u+ R; B    set my-column -1
+ t. w( R- `  Z4 j7 G# a    set my-phase -1/ p. v5 \6 j0 x; x
    set pcolor brown + 3: t" n2 u( D  J7 K0 }
  ]& h! p. x: N7 ~! r6 a7 F
% x. H! l% z/ w& M/ t- G, d) ~
  ;; initialize the global variables that hold patch agentsets
& w5 K$ |5 a# `) }1 d: L! O' S0 c- s  set roads patches with" b/ b$ |& j" ]1 ?
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 i/ P$ T- {4 o# T
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 P5 P$ }4 ~+ B) j% Y' G  set intersections roads with
# Y, r  j, c9 }! P6 k    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and: s: s3 E& s& {" v, f. `, C- ^  K
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- T; S: G% }) I+ t
* z% j: F" C% K# G
  ask roads [ set pcolor white ]: B: {+ y. Y1 i4 F- ?0 S" {6 X8 L
    setup-intersections
7 y' R1 ?% o1 t4 M  k5 wend
8 D, G/ u7 M! b其中定义道路的句子,如下所示,是什么意思啊?) e8 k4 s4 g3 `% b" O) [
set roads patches with
8 L7 S3 ^3 L$ B2 B4 `; Y+ \    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& F2 k) G! L! C7 R1 y5 r    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 c# w" K, K& m4 b8 q4 t8 |7 v0 }0 T
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, 2026-7-15 23:40 , Processed in 0.013280 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