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: 8000|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" o9 a8 `! K$ Rnetlogo自带的social science--traffic grid这一例子当中,
1 A) A7 V4 G- W! T4 tglobals# m0 h0 d8 `! C; J" E8 i. ?
[
, o5 J0 C- ~, |  grid-x-inc               ;; the amount of patches in between two roads in the x direction# a# P* P! y2 q* R  R( r
  grid-y-inc               ;; the amount of patches in between two roads in the y direction/ D- I% M- X& ]
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if4 U' D$ {8 a: Z. G7 `$ w' [
                           ;; it is to accelerate or decelerate  q6 m7 B  N) |% w2 n7 n9 z
  phase                    ;; keeps track of the phase* t4 ]* B9 K6 [9 {
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure+ A/ \3 L1 [$ p& J4 @9 M
  current-light            ;; the currently selected light
4 j2 X' ~9 Q& R9 w' x% t" d
# E: I/ J# s) Z5 ?* S2 k  ;; patch agentsets
5 `+ X1 p' y+ g1 \) i: ^' W! |  intersections ;; agentset containing the patches that are intersections) s8 [; d+ \: j4 q
  roads         ;; agentset containing the patches that are roads( ]# p" S$ K5 Q  }, C( R8 X
]
3 R& |# Q7 ?# p/ l6 c
) ?) B8 l. [! k# cturtles-own6 E" ~% X7 s* c& g
[
5 D8 q; t' b3 S' L6 Z! l  ^! ]8 \& O  speed     ;; the speed of the turtle
# v5 E* {( i! y5 R  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
# I0 y- t6 }2 N" x$ ^0 y  wait-time ;; the amount of time since the last time a turtle has moved; L6 Q( u# b/ I6 q& v& p9 l( U
]
  k4 l0 L3 t* {+ D+ L6 B
1 o% T* r( _/ Zpatches-own" o5 T3 z" t) h" {% ^+ \
[% d* f# L1 o7 x5 F6 a* c
  intersection?   ;; true if the patch is at the intersection of two roads8 p1 x( t; q9 r
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
. x9 N8 R1 h6 T! }" w: c                  ;; false for a non-intersection patches.
1 I0 ^6 c0 J$ F+ u' D5 R& F  my-row          ;; the row of the intersection counting from the upper left corner of the
" B0 ]3 P* r  t$ O                  ;; world.  -1 for non-intersection patches.
! r+ H1 [- J3 X; i6 }6 A  my-column       ;; the column of the intersection counting from the upper left corner of the  |( ]( U6 [% U% S( g  j) l/ u
                  ;; world.  -1 for non-intersection patches.9 Y) [$ {- `  v% v1 ^3 Q4 p
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
, M( K& t( X6 n) `8 o/ R  auto?           ;; whether or not this intersection will switch automatically.
" r: }: a# `4 ^5 k) n                  ;; false for non-intersection patches.
2 K) d! P! d8 j$ V- i" L0 m' \5 B]
3 b- \6 W' f& G, Q+ G  {% Z2 c$ W, t, l; e  l4 l: `
; B! S4 f. f% o. y% A
;;;;;;;;;;;;;;;;;;;;;;1 |2 V' ~. T& Q1 G# t( x
;; Setup Procedures ;;+ h$ U- d" A8 H: D& z8 X2 s, r
;;;;;;;;;;;;;;;;;;;;;;
8 `& |" x/ o. \* \1 t+ f3 m: o/ D4 @0 X
7 Z, a# q) _) d9 V# R* y& c;; Initialize the display by giving the global and patch variables initial values.! [5 J7 n; Y+ R9 i
;; Create num-cars of turtles if there are enough road patches for one turtle to1 P" F2 t5 ~" m
;; be created per road patch. Set up the plots.
2 M( U5 ~8 i! e3 h; |: X( H9 a9 qto setup/ q) q2 K5 P& M% @: S" m, w
  ca
$ w. e! m) S; e6 H  setup-globals9 Q1 R% F$ S6 D6 K/ h

9 ?1 |6 t) [/ K/ ^  f  ;; First we ask the patches to draw themselves and set up a few variables* c  S0 Y) Z) K2 k" t
  setup-patches
( S& n" Y( D9 w- q8 @8 _  make-current one-of intersections( {8 k5 W8 Q. h2 i* j. |2 t
  label-current# U' i7 {6 l' ?9 p; j5 L9 [( g

4 U; u; E! J. G+ P* W" A  set-default-shape turtles "car"
: t& _$ @9 v+ r& E# M2 @' z" b. ^/ I; g/ c3 c% L( q5 {, A- L
  if (num-cars > count roads)* x, }  S2 w. v
  [7 y# ]1 ]& I  c: \
    user-message (word "There are too many cars for the amount of "
4 @8 `- O2 w' H0 r+ t                       "road.  Either increase the amount of roads "
( ~7 z6 K+ K* l" B) D9 _! ^: }  H                       "by increasing the GRID-SIZE-X or "
5 S4 r' _- c8 R3 ~- T9 K* `                       "GRID-SIZE-Y sliders, or decrease the "
8 [8 ^! M' l5 Q7 f- L                       "number of cars by lowering the NUMBER slider.\n"
9 g3 ~" C. W9 X5 K" Q                       "The setup has stopped.")
: r! `$ u- G" o2 D    stop' O- h- W/ [+ a; Y
  ]3 @& P1 M$ o3 c3 g9 I
- Y; G5 s. v7 J* _
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
% w, R* l2 D, O  crt num-cars
" V2 O9 g1 {8 H, E! o, g: ^  [) z2 m- K8 B# a& q; [  j! P
    setup-cars9 ^7 [1 ^9 n2 \
    set-car-color
+ A) K' \9 u, K4 _    record-data% i* I* E! l' e
  ]5 ~# v. o" E: n( Y2 S

- c" {' z# C% |$ v/ ~* ^  ;; give the turtles an initial speed  N+ _: ~" M5 u: @3 X6 {
  ask turtles [ set-car-speed ]
! `  X* d" O% U' n; P5 |; a. a- V' o* K( ]8 q, a9 {
  reset-ticks1 M) J4 d3 C! g  P
end
5 x5 m, S+ B6 c) \3 x: Z- M( E* o. g3 N# ^+ d( U8 V. X
;; Initialize the global variables to appropriate values" u. u) Z, G- h# B: g. Q
to setup-globals6 n9 l: Z- l8 D, a, \
  set current-light nobody ;; just for now, since there are no lights yet
: V4 w  }4 Q! |3 y- U  set phase 0
& w$ I5 T- e! l; `- @6 B  set num-cars-stopped 03 J/ c# `& m9 V3 F6 `# j
  set grid-x-inc world-width / grid-size-x8 e* x# P& S5 S1 Y- E' ^. x. W
  set grid-y-inc world-height / grid-size-y
  |: [. X$ J: Z) }4 U/ S& K
  I  B/ n, R, ~* t1 @% \  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# Z8 b* A4 c' h1 J+ {+ u6 k! n  set acceleration 0.0998 e! k. O; \; X. Q. ~7 O$ \# _
end
* d" c7 z% C1 F, F9 n- T$ H; P& W+ s- g; S
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
! ]! _5 g( p) K3 f" T;; and initialize the traffic lights to one setting
* O- n& B- u) \to setup-patches/ d* V/ E# O3 [% B# F6 a( V
  ;; initialize the patch-owned variables and color the patches to a base-color# {! m$ ~* e9 P3 p4 F- t, G
  ask patches
0 s/ @+ F: _7 {9 K% ~: R, h1 d  [
  `; B' ^( P3 }- Y& X5 _    set intersection? false
1 H6 X& t; j# |9 K. C    set auto? false
, E" E: I7 U5 F$ w% Y  y4 j4 o    set green-light-up? true# i" W  n8 y6 z# B
    set my-row -1" _- z5 b$ @& d( B
    set my-column -18 w, s/ e+ g, s
    set my-phase -1
' [$ ?. ~/ f9 C, I" x2 D0 O    set pcolor brown + 3
+ F, S) T0 a7 L$ T  ]& N1 a* w% q. T2 n: @8 f  |
6 ^& L' |  N. e8 V3 Q. w) H9 L
  ;; initialize the global variables that hold patch agentsets+ G' q; e/ m7 R7 m& f, ^6 r
  set roads patches with
$ ?3 e" o; I% `8 u$ N    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) |, `: P# U8 }
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" R7 Z" c9 G* G5 ?8 H  g9 I! H  set intersections roads with9 r) S' l! N2 B6 a
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
7 X7 E1 _8 m7 b4 ]7 F3 b3 Z    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; Z0 ^9 M2 u9 b0 b, C  S" F

4 z4 O# M; J, N' o% G. F: P( M  ask roads [ set pcolor white ]# g- E2 b/ k# L7 J5 E) O& a3 A
    setup-intersections
- z, l- F9 J/ k, P8 t0 E1 t' Oend
7 y8 r' f! @0 a2 l/ I! Y# L其中定义道路的句子,如下所示,是什么意思啊?" B0 V3 T& g9 U
set roads patches with
0 W9 S7 C6 Y3 T+ P8 [/ ~    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 L# ?7 m: u* {6 M
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)], A2 E7 t7 N; o! u  c
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, 2026-1-27 09:42 , Processed in 0.020230 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