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: 9590|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。; B# d5 T3 w. G% o8 C1 y- j
netlogo自带的social science--traffic grid这一例子当中,- Z: [$ i- }# z% K3 p  ^
globals2 e$ H! g, u6 k. x; y9 X* u% X
[- p3 ?- _" Y- P
  grid-x-inc               ;; the amount of patches in between two roads in the x direction0 w7 s* @4 y' W: O( z
  grid-y-inc               ;; the amount of patches in between two roads in the y direction
) v4 X6 K: C2 K  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
5 v: h; A. Z+ x, S) x+ n' q                           ;; it is to accelerate or decelerate
/ w8 Z  `3 o9 C  phase                    ;; keeps track of the phase) f7 c% ^. D) v# J
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure" V7 {- H) c5 {. m% m: [
  current-light            ;; the currently selected light: A4 m7 \' y6 ~) ?5 `) ]
! h' h. s# K, ~% N9 `
  ;; patch agentsets  O! L% b4 O. P
  intersections ;; agentset containing the patches that are intersections9 K, M' M4 e* o. V% @
  roads         ;; agentset containing the patches that are roads
, Y: B6 c7 o9 i+ ]]& }" C  l4 t  x* z* K) Y7 g
) c, S( E" i7 v5 V2 k
turtles-own3 T" D6 A" Z7 H( D, v
[
" {8 h/ ^! H0 h+ o- S) A! _  speed     ;; the speed of the turtle1 C1 b+ a" X, k  V0 @& S
  up-car?   ;; true if the turtle moves downwards and false if it moves to the right/ ?& m0 Z1 T- U, ~" F
  wait-time ;; the amount of time since the last time a turtle has moved, s+ _) \4 l8 Y$ x5 ^
]3 }( X  \% d7 e1 ]# s) |4 a

% b4 T3 u. ^: Mpatches-own
7 R5 K8 t& s3 D! K' s1 T[
; _  x3 m5 }( }& g$ a5 D  intersection?   ;; true if the patch is at the intersection of two roads) _2 G3 t$ Y; E% e5 t/ O
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.; q: L7 ?& L  S. ^! S( ]# R7 F7 t  U
                  ;; false for a non-intersection patches.
, z" ~2 `. ?1 Q" E" w  my-row          ;; the row of the intersection counting from the upper left corner of the+ k* F2 M. g' K0 W) r9 B
                  ;; world.  -1 for non-intersection patches.
& D$ b' W6 ?) c# G8 _, f0 o  my-column       ;; the column of the intersection counting from the upper left corner of the
$ V6 T( A; x# M: n! f( J) D                  ;; world.  -1 for non-intersection patches.
! t; ~- \9 h; O$ ^- n" o) j" ^  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.! v  L5 @. G4 ]: l1 U
  auto?           ;; whether or not this intersection will switch automatically.5 j* d2 B; G9 z0 K) Z4 o- J( E
                  ;; false for non-intersection patches.2 F# B% ?5 ~8 H4 E4 x; o
]
# G& }7 V( k& J3 c
3 S7 W. J3 Q* a  f2 P7 w, e# V, n4 v6 O( ~
;;;;;;;;;;;;;;;;;;;;;;
& T; ]- @# y& |* J$ A;; Setup Procedures ;;# b$ y) ]' `. r+ _
;;;;;;;;;;;;;;;;;;;;;;
2 S+ a3 {; ?) e' J" `& \4 P& g+ h% d& }4 g0 D- s* b5 C
;; Initialize the display by giving the global and patch variables initial values.
" \( `1 _0 x0 f) h8 J;; Create num-cars of turtles if there are enough road patches for one turtle to
! Y8 W* b! `7 }& Z3 r. v;; be created per road patch. Set up the plots.- \3 Q" k) p6 V" A
to setup
: A. _, i4 B/ m( L: S6 c  s9 Y  ca
1 k, C* N8 a' q5 U$ M: H* u$ F  setup-globals
$ @0 k& u! L. u/ H
+ O9 \/ _) x/ B( \6 I0 F( X3 i# w  ;; First we ask the patches to draw themselves and set up a few variables/ S6 r/ ~8 d/ D+ r2 ?7 S1 U
  setup-patches
6 G) E% F* J  j: v& B% N  make-current one-of intersections
; ]9 ~9 S5 x3 ?- J$ h# S/ f5 g- }  label-current
: n( |! h/ }2 x% i- t- s* p
$ b& n9 }% E3 S2 L# x* q6 Z' [1 P  set-default-shape turtles "car"
/ Q# p1 r! w& \3 e( Z* ?0 d0 Y, Z, A1 F3 A) p* Y: L
  if (num-cars > count roads), y& N- s0 [0 d8 y1 D( R  r7 E3 B
  [" n/ a& _; J- A1 {9 e
    user-message (word "There are too many cars for the amount of "
5 `; C% A2 W" x8 Z4 d' E8 S0 z: a                       "road.  Either increase the amount of roads "2 g. y; X0 W- d- V  q; |- \: ?. S  F
                       "by increasing the GRID-SIZE-X or "6 M- |- u: X' A9 [
                       "GRID-SIZE-Y sliders, or decrease the "
* C4 y. e, U1 {0 h                       "number of cars by lowering the NUMBER slider.\n"
* m* F- L3 U& _3 J                       "The setup has stopped.")1 P8 v8 @7 L6 r4 F
    stop- C9 I8 n6 S4 A, ^  h! w4 B" e
  ]
/ k! M2 x! Z2 n4 H. |  U' w
* U  ^$ g! T9 U" c$ l  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color! E7 M2 S! W, q7 q
  crt num-cars
  _+ d* x. W0 [1 b: P  [
+ B, o- ~! f& s0 _, Y1 M    setup-cars) `0 E, I  J, w1 \
    set-car-color# u3 D5 J0 W' i% H2 n, l$ F6 C' h
    record-data/ H+ W3 H. q! t! w. P/ Z
  ]7 b* ~+ Y8 ~5 ^/ F! b  h
; b' v1 E% R6 p
  ;; give the turtles an initial speed' a+ j, c+ H) u
  ask turtles [ set-car-speed ]& c; w* D5 H5 `0 v5 M

* s% O/ Q) g" g7 @; i2 ]  reset-ticks
6 Q  I, q, {1 h9 V6 Cend! k/ w! A* O3 y! e" V' H# b6 U
! c) X9 I. g% E8 O& f5 s% P
;; Initialize the global variables to appropriate values
+ ?* \' n' m1 n6 n" j4 Kto setup-globals
2 w' r& ~$ f( f0 Z7 ~: b& g8 b" a  set current-light nobody ;; just for now, since there are no lights yet
# }0 p- Q- w- R5 c# _7 y  set phase 0( w% \2 G# E$ D) W
  set num-cars-stopped 0
& a- m: O2 }9 Z1 T! ]8 y  set grid-x-inc world-width / grid-size-x) w* ?; a# E" E+ Y! M7 j/ _. K
  set grid-y-inc world-height / grid-size-y8 _: r9 A: Z) g1 F! o* F
7 A0 m) y8 r, D4 G
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary# G6 Y; ]9 L1 R. D; ?) a" A
  set acceleration 0.099) N8 y& A" F: L) ^
end) J8 }& E0 a, s, ~4 D+ j

5 A9 o/ r, ~' }  w# l) A;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
: M1 m! _# o" A5 L4 Y0 u+ v: |;; and initialize the traffic lights to one setting
" L2 k- k5 G2 P) K6 T& lto setup-patches/ w- J; H  I# i7 L2 K. @* V
  ;; initialize the patch-owned variables and color the patches to a base-color
- n" J: T5 P+ C" `2 Z  ask patches$ q, a! I8 j% U/ h: K8 F
  [
7 C% R% Z0 h1 n4 N. w" E& V    set intersection? false# J0 D; L* m" z* }
    set auto? false
, f- f( ?: m$ U; g& a1 \, \/ }    set green-light-up? true
+ S" D( a7 ~3 b; E2 n    set my-row -1
! y. v# ^  b# a0 a; l" |, y  R  ~    set my-column -1
9 [: _3 `0 v& E. ^3 ^    set my-phase -1/ x/ [' M5 l, |: U  l" o  o
    set pcolor brown + 3" O; U% J+ T. ^9 T2 D
  ]& A8 O( i! m0 ]: M6 S

8 _& B# `) P/ h. H4 n6 g  ;; initialize the global variables that hold patch agentsets1 J/ \: Y  h5 v- z% w: J
  set roads patches with& P) N( d, E' `% |* E) k
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. W: m' l! n6 B! M1 R    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. p9 O+ h4 H8 Z8 F% q; k8 d( t! @( e  set intersections roads with
5 @7 S9 w# y: x3 R0 Z: {    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and9 a8 w: T' Y) |6 ]
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 }+ l4 _% n& H5 C, d
( \' w* N4 L- U6 [1 x* ~7 F
  ask roads [ set pcolor white ]
: n. M: ^, U9 y) P0 p  z) w    setup-intersections8 [& o0 d' _' X9 _
end
( k0 Q: d7 R  V* q* R; b& T  I其中定义道路的句子,如下所示,是什么意思啊?3 k9 B1 @1 M% z2 [3 S
set roads patches with" v! `+ M3 d% n$ L# k1 ^& D0 r
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
3 c$ B- M8 M+ Y5 S" I6 x; Y) D- V    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 P2 x3 l5 I9 T3 q
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, 2026-4-23 02:43 , Processed in 0.016672 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