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: 8996|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。
8 o! M( r4 S& V: _, i6 Fnetlogo自带的social science--traffic grid这一例子当中,
5 T/ J: u1 p# Gglobals
" ]- |6 K, m, E: w9 [- z[* P+ e, P( w# [/ t. q1 y* n2 U, |/ o
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
8 Q+ Z3 j" M  z- _  H4 V! l  grid-y-inc               ;; the amount of patches in between two roads in the y direction- `3 o5 r7 b1 v1 j* C
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
6 a# q& ~, T  ~0 e" h! q6 }                           ;; it is to accelerate or decelerate: U) ]! P- B; U/ W& A
  phase                    ;; keeps track of the phase+ D7 W  [) O: `' X( S2 H
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure6 Q0 Q' E. }# _" ~! k( N2 P. o5 }5 n
  current-light            ;; the currently selected light
6 q! U7 T1 Z# {' d8 I
9 ]& J6 S3 e0 l' Q  ;; patch agentsets' _' k+ W6 D& n$ N
  intersections ;; agentset containing the patches that are intersections
7 g( V- x, f2 w6 @  roads         ;; agentset containing the patches that are roads
0 ]7 ^- q/ x& x& j9 \7 l2 []& E6 s7 a; J  j! ^+ A

! f- d3 j/ c+ f- X) Bturtles-own
3 C$ W  D1 i) D% T( l6 x$ x[
5 J8 b* X2 \7 G# X( F' j1 y& A  speed     ;; the speed of the turtle# \3 V  i! E1 {, L  Q5 |0 v, _" q" i
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
" [- s' B$ e- }: U  wait-time ;; the amount of time since the last time a turtle has moved8 {9 O/ Y  A1 h6 Q* X
]$ E( e% Y: h- g7 n' d

$ G. K) q- s, m1 {patches-own1 z/ _1 _; \' B( p( y& Q: q  J
[
: r2 t. N" r9 C  intersection?   ;; true if the patch is at the intersection of two roads
  `; q+ M" V0 g; S  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
1 ^8 Q% U; Y) o$ }0 T6 [                  ;; false for a non-intersection patches.
3 Q- T8 Z2 s4 |  my-row          ;; the row of the intersection counting from the upper left corner of the
) K" e  S1 T* v/ p8 b# ]: W3 W                  ;; world.  -1 for non-intersection patches.
, j' h" L9 }$ o& s, V4 T  my-column       ;; the column of the intersection counting from the upper left corner of the1 N, O7 }" o2 o9 u' G  h4 r
                  ;; world.  -1 for non-intersection patches.
  {9 N8 t! h: d4 Y$ x$ c4 _  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.7 T, Y: E% w9 \
  auto?           ;; whether or not this intersection will switch automatically.
2 ^% B6 y5 b' o: u                  ;; false for non-intersection patches.
# b: }/ H& @6 W5 b9 ^9 }]6 B1 A$ ?5 K, `3 o1 S5 v. d
* k9 s7 a7 j2 t% \( z" B( c8 o
! C2 P% o8 c4 P- l1 j" u: X
;;;;;;;;;;;;;;;;;;;;;;. p& t2 r8 K$ O
;; Setup Procedures ;;
9 H0 h: X# r& z- N8 F; w;;;;;;;;;;;;;;;;;;;;;;
  ]1 Q6 s" d. A5 H' B. Z6 B+ w4 p( W' `8 ]8 C8 T( {6 p
;; Initialize the display by giving the global and patch variables initial values.
0 C# z: n% B) X;; Create num-cars of turtles if there are enough road patches for one turtle to
1 F" X  P" l; M2 h5 e( u;; be created per road patch. Set up the plots.
& `7 @$ j; g5 ]6 A; D  [to setup
# U3 e; x, ~' ?/ Q. f  ca5 @- c+ I% S+ b
  setup-globals
. z2 J+ }# Y: F; p7 r9 p6 ^/ D9 S- E; f( X7 u4 X
  ;; First we ask the patches to draw themselves and set up a few variables
+ w. A2 {6 d9 E( P  setup-patches
, `! y5 M1 `1 o4 m; W6 j  make-current one-of intersections
* U! r7 s% E0 F  A8 m  label-current7 m& l  V% U) _( D: L. b

! V6 b) j% l- A. c  set-default-shape turtles "car"/ I$ B  o. N4 h" |5 `
- s8 I5 r* \. }; e2 S- M4 O2 F
  if (num-cars > count roads)
5 Y6 v1 k" n# f, a$ B0 X  [/ K, M+ j. E( i% H/ S
    user-message (word "There are too many cars for the amount of "# {, j% _1 h, P5 w! z1 t) D
                       "road.  Either increase the amount of roads "4 a+ Z! v) ]1 n- n* c7 ^4 ?
                       "by increasing the GRID-SIZE-X or "
. \% T, A; B8 T8 e                       "GRID-SIZE-Y sliders, or decrease the ") {7 a" `- D; u0 Z9 ~# j
                       "number of cars by lowering the NUMBER slider.\n"
" P$ H$ c& y6 u$ S2 A  c7 ?6 z, `7 m                       "The setup has stopped.")
) y" k  J% h( V+ x4 G    stop7 x/ L* Y; o# `6 A/ ?( V/ D
  ]7 U" V1 V' T8 P; B$ L( [
2 ^) C. D5 J1 d8 S& ^" c( x
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color! }# x* i9 O  w0 o% \+ J* r
  crt num-cars* [6 L* {* ]% |( ^
  [
* g) _( k+ c* E6 q  k* s: H; V" Y" t2 p    setup-cars
1 `: N- K8 M7 Z; Z/ |    set-car-color
& V/ e3 s. f% t  O. ?% \( y& r% }    record-data
5 v6 }9 D$ @; O6 Q. U& _' a/ T  ]
  `* c3 K. I7 Q8 `; [
4 H( G) u0 G# Q4 `8 J! T. g* M. X  ;; give the turtles an initial speed. Z  M( F! M3 z( Q- H  j
  ask turtles [ set-car-speed ]; @. o" M9 |. h# q" n* i2 z

4 c* A' ~$ m+ M7 u' d2 `. l! v  reset-ticks
1 g; o9 h! L1 nend
5 O# K  E2 [. j; n/ B3 v! e7 \) b; U* ]" |
;; Initialize the global variables to appropriate values
/ y2 T4 [4 X* m  nto setup-globals
8 ^0 a* h. \# Z8 |. D* f  set current-light nobody ;; just for now, since there are no lights yet. f( s7 j+ F9 G
  set phase 0
9 j# o" v' _4 A  set num-cars-stopped 0
, z7 `: o. n3 X* X: i  set grid-x-inc world-width / grid-size-x
, b2 u2 ]0 ?5 @+ l  set grid-y-inc world-height / grid-size-y3 @5 X: |$ d# W5 e. J
( x" T7 u( u* P: `" s8 }0 {% b
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary7 H  `8 {  Q& y7 u
  set acceleration 0.099
! Z3 O5 E, N/ n. E# I6 Wend
/ O& f* D) O; \/ z. y9 n% e2 k0 I+ v  L5 [4 i
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
/ R( b, C" \' k# [% H! \6 V;; and initialize the traffic lights to one setting0 u5 z  C) V2 L! l' ]- H! C6 G! _( n6 p
to setup-patches/ D  {0 |5 j6 ?! F3 B# y7 E9 g5 {, ^
  ;; initialize the patch-owned variables and color the patches to a base-color  a3 n/ `  u2 e  ?
  ask patches9 P# j& O1 N8 k. ?
  [# ~+ h& |6 m- v9 D- [
    set intersection? false
, ?$ X6 H& ?: s9 w3 f7 t; R    set auto? false
* I3 k' |, l4 ?3 O0 g0 G/ }( O+ D9 H0 f    set green-light-up? true7 c1 S# Q8 P7 k9 A, r7 S/ N
    set my-row -1, S' O% ~" ]0 Z: u- s7 F7 I
    set my-column -1
+ g7 O  D- X3 N4 f1 Y' r    set my-phase -1
; A. H' [6 H- U+ e, }    set pcolor brown + 3
0 t3 q9 g* G# e% U  ]
: q' K+ r- H+ i! Y: w, O2 A, ^
3 s! Q* j3 k; j& ?% S  ;; initialize the global variables that hold patch agentsets
( J& W9 P; L, D1 X6 v. i' X% a  set roads patches with
0 s+ A1 l3 h# m4 c  z( O1 W    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 R1 D2 T1 c; z# W( w    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ G( B0 X9 N( n2 }
  set intersections roads with  |! }( D/ k4 t
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and9 r4 k1 B! \, d+ R
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* ^. `6 H) G7 m3 S: M# l

/ _( ]/ V) C- ]) \* E4 X1 ]  ask roads [ set pcolor white ]7 s+ S$ L+ s! Y7 q, S9 A
    setup-intersections
! d0 b1 S* x2 l/ b# Yend6 O5 \' `, Q% L9 l
其中定义道路的句子,如下所示,是什么意思啊?
7 a$ v! N! B7 h5 h) x5 S set roads patches with
* }( b+ d. I6 x9 \& @: C' o    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# }% m& B! R; \9 t$ m    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
7 N1 s# \9 g- K- y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, 2026-3-21 11:00 , Processed in 0.017071 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