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: 9390|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。) n( g1 S  T3 M1 h6 G
netlogo自带的social science--traffic grid这一例子当中,+ G5 M# `0 _# ~/ n( i1 R- R
globals
" Y; v) S5 f1 Z[1 p! p  u; X6 {2 b8 A" \/ r
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
" E% g1 A1 h6 w) Z5 O$ ?/ P  grid-y-inc               ;; the amount of patches in between two roads in the y direction+ o' d5 O) P. \& T  G3 x
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if7 Y+ g8 {' V9 H. {% D! v
                           ;; it is to accelerate or decelerate
+ h/ P( a% x1 H& m  phase                    ;; keeps track of the phase
4 p% J- j$ T' K: A$ x" |  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
5 V* Q8 _5 p3 v  current-light            ;; the currently selected light$ ?& _5 K1 V9 p9 f" F6 m; ]: {; q
, v8 Z4 b9 L% }0 B5 M7 _  q
  ;; patch agentsets0 `  l' ?3 o6 u+ j. ^- P0 j
  intersections ;; agentset containing the patches that are intersections
/ R( f3 ~' _8 F& z, y" I" G6 p- ^  roads         ;; agentset containing the patches that are roads8 R% c; \4 l2 \* D
]
5 N- j9 s2 x! ~6 N& k$ D9 S
$ Q- K7 y& |) Vturtles-own
% l7 s  Y* ?6 |/ X/ I[
( I+ c5 }, ^. z- Q$ D* P  speed     ;; the speed of the turtle
0 a: [( h$ K/ [; j. C& |, n/ T1 d  up-car?   ;; true if the turtle moves downwards and false if it moves to the right1 u7 r9 T: B6 {" f
  wait-time ;; the amount of time since the last time a turtle has moved" v+ N* d- _4 ~1 r6 X9 h
]
; F: v- Y' |$ o2 K& `
: S0 {- a5 Y7 w9 F6 T! J* dpatches-own
  b2 w% w% |+ E1 S- S3 f) m5 m[
! _: ]% n$ Q2 O2 z# }* n" e. i' i  intersection?   ;; true if the patch is at the intersection of two roads
0 b7 x$ Y7 T# Y: v. C% i  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
* a9 j- @0 c8 u9 _8 L% B                  ;; false for a non-intersection patches.
0 i' Q" D& e8 Z1 ^' l( ]+ G7 Z  my-row          ;; the row of the intersection counting from the upper left corner of the7 Z0 Z2 M/ |+ B+ a/ P; [8 j
                  ;; world.  -1 for non-intersection patches.
& D, u, r, G* V# ]  my-column       ;; the column of the intersection counting from the upper left corner of the) Z$ {& J3 [4 }0 M' W) n
                  ;; world.  -1 for non-intersection patches.' ~) x! U7 B0 A/ w+ d0 U6 }8 x
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches." s; L' Y7 }8 W% p4 \! a) C
  auto?           ;; whether or not this intersection will switch automatically.8 Q' u; X. t- P5 j5 o1 N. l+ ~
                  ;; false for non-intersection patches.
: ?8 H% c- E: X) g& ^]
# ~# z- ^* j; c. `& `/ ~+ Q
  ]2 i; B, b" t  d2 ], I& _2 ]6 {: h5 ?$ e2 X
;;;;;;;;;;;;;;;;;;;;;;9 k* R9 T! t. M9 A
;; Setup Procedures ;;
: j" F3 r$ G5 J7 `9 u% B5 A3 k0 L$ k;;;;;;;;;;;;;;;;;;;;;;5 F9 a& Y& Y+ j) w# c4 N
# T. m( e# y4 u% a: W1 P
;; Initialize the display by giving the global and patch variables initial values.
# c/ D- h2 i; `+ D. j. p;; Create num-cars of turtles if there are enough road patches for one turtle to9 ]7 n" u9 X0 e( V
;; be created per road patch. Set up the plots.2 d2 |2 I; J/ z+ c7 e
to setup
# |1 ]. s" h, u! @  ca/ `% Y/ m0 M; R! P
  setup-globals' `5 S* W0 Z6 }

: S0 \9 X4 J. [- c% n  ;; First we ask the patches to draw themselves and set up a few variables$ ?- x; P2 X: [& o6 `1 S2 Q
  setup-patches
% Q8 A4 |) k! h* y% O+ l3 j  make-current one-of intersections' I) ?4 y! d8 Y7 L
  label-current
9 g" d( ~) {2 Z8 m7 `$ y  I; A! [/ `1 r1 e+ P3 {
  set-default-shape turtles "car"
8 n/ V9 {, ?/ h1 Y9 v% B4 J, E& v" U! D0 n
  if (num-cars > count roads)1 i/ a" }; g5 Z5 T- R. J: w
  [
' F) i, ?* O8 {0 A5 z; {    user-message (word "There are too many cars for the amount of "
% s9 C( x- A5 W                       "road.  Either increase the amount of roads "4 t  k  s! c6 i& w' d% |
                       "by increasing the GRID-SIZE-X or "
. c% }' l& q$ k6 X6 W# a( e, k- I8 K& i                       "GRID-SIZE-Y sliders, or decrease the "
; B6 V8 \" h6 a, C; _6 L" _                       "number of cars by lowering the NUMBER slider.\n"; u6 x5 V2 C) N, {3 D7 Y: O
                       "The setup has stopped."): t+ V' {# \6 S; O4 g7 \6 h
    stop" V( R3 V1 x; ]0 A
  ]
" i7 s. B+ G7 N# p0 ^0 I, c8 U  R; C. T% [
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
* @+ L7 ?% \* X  crt num-cars4 M. m0 Y9 |; n5 n% x
  [& H( y- L, z3 {5 k  p1 L
    setup-cars
0 @( M+ B" Z% w: o    set-car-color
5 f& V  Y( q% G6 W    record-data2 t( _& X4 Z7 @4 n% z
  ]
0 N! r7 ?1 U3 D- R: M- g. z3 @
; [7 @- h: d2 s) D  B" b! ~  ;; give the turtles an initial speed
6 a/ m/ b8 \# T4 S0 |  ask turtles [ set-car-speed ]
+ G( @; @- g6 c( ?+ i3 }# Z8 W4 q& ^* @' g/ d% n
  reset-ticks; y5 c& X" B9 O
end
9 ^  w6 Z( M0 g
& J  T3 |0 y, E# \5 F1 A;; Initialize the global variables to appropriate values0 Q+ F6 |6 C  e( J- d( S
to setup-globals
( ]# R8 a8 ~# R4 N  `( r5 Q  set current-light nobody ;; just for now, since there are no lights yet. l) }3 ?- l- _$ I
  set phase 0
5 @: N- W, `/ f+ u1 K/ M' C# ~& B  set num-cars-stopped 0
$ E# v  p: Z5 P& J% W  set grid-x-inc world-width / grid-size-x
+ q5 V0 s& f) D; c  I' o. B2 w  set grid-y-inc world-height / grid-size-y) G7 |0 d( Z, F, V3 f

; ]' \: i$ o! J. a1 Y; J  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary. ~) o7 p9 J% \; R0 c! a, I, N
  set acceleration 0.099
8 W  x* ~1 l' Hend
4 W( u3 l( n9 v/ q
. m6 X; y# t  s( p, B$ ]5 X. z- E: Q;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
% K' m$ D( P" t; i5 \0 V;; and initialize the traffic lights to one setting  {! y% O. m$ G8 Q5 `% Y
to setup-patches% ?: j& D" V) ]' v+ b* w1 x2 p
  ;; initialize the patch-owned variables and color the patches to a base-color
/ k& L8 J0 I+ ^  V  ask patches/ r, z7 P7 o9 R& ~
  [8 H+ O) g9 J* _
    set intersection? false. m. D* M! }( W. |' a6 a- E/ \
    set auto? false* `, F! ~0 C! U8 c
    set green-light-up? true' w4 i' D  U4 O7 R# t$ D
    set my-row -1; ~* V: C2 ]# x% K  i7 q
    set my-column -1
0 i8 Z% S: E, K! U8 E    set my-phase -1
3 G6 @  h: Z' ]2 D! V* u    set pcolor brown + 3
9 z# k3 j) u7 \; m  ]
# A4 l9 u* t* e, _1 W$ a$ u. E8 z: a& X# h8 v( \1 P& T6 i
  ;; initialize the global variables that hold patch agentsets5 ?3 R( J0 [8 b# [! d) b
  set roads patches with- F: \5 V$ z' l+ G, f& j
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 W. A* D8 ~3 {/ m1 M& G
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
  j$ @3 |6 t1 O* o- u  set intersections roads with
/ l4 `5 h( ?0 y& p5 o9 ?9 c% A, J    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and+ ^/ J$ N/ \4 ~7 D3 V" [. W- g) C4 Y1 q
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ e1 e& F% D# B, S4 j) T

$ F$ o, x: w) n- m9 I3 l3 u& u  ask roads [ set pcolor white ]
) v8 @: i+ A1 W% o; D4 g& n    setup-intersections
8 G+ B  C5 |7 X0 x# u  q3 Bend
5 D9 z& s, O9 }  b其中定义道路的句子,如下所示,是什么意思啊?4 u- i2 {6 O/ a( R
set roads patches with( Z7 v5 L0 q9 ^! k) D2 L, v9 m+ h
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. c- K( y2 R3 V3 x
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 c4 X. m9 ]( ]5 @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, 2026-4-13 04:04 , Processed in 0.015253 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