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: 8846|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。4 j+ }4 E+ h2 ]
netlogo自带的social science--traffic grid这一例子当中,% E* }# z* K+ G+ ~; f- M& w+ D
globals3 x  x$ a* o" j. t  G
[( I2 W2 x; W: G1 Z1 T+ F
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
4 G8 V' D+ G1 j" a7 C  grid-y-inc               ;; the amount of patches in between two roads in the y direction" Q# k# }2 ]# ]2 t
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
7 _; T% ~4 a) L# w# |) J                           ;; it is to accelerate or decelerate
! o( p, P5 A3 T. D6 W( Z  phase                    ;; keeps track of the phase2 t3 s' `. }1 w) R+ |: V- [& `
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure
. k" H2 j. C: X9 u$ x  current-light            ;; the currently selected light+ b, y" C8 c3 A- b8 I7 `, ~  }  i
! \) R, b/ G: M  U, V( f
  ;; patch agentsets
+ x) E6 I; t9 A/ l3 r  intersections ;; agentset containing the patches that are intersections5 p. }: m7 A# \; f
  roads         ;; agentset containing the patches that are roads7 V7 |5 K" |( @
]" }7 S/ l9 s: c

+ j# V0 `' t. A6 v( ?; tturtles-own% v$ M- H! `; N) P/ _' D' G
[+ H4 B1 l  J5 R: E( ^+ @. c. D
  speed     ;; the speed of the turtle
, F. q& T8 W+ k0 Y, u  up-car?   ;; true if the turtle moves downwards and false if it moves to the right- ?3 {- D) D# \+ [+ ?) s  [  s0 i
  wait-time ;; the amount of time since the last time a turtle has moved6 N, d& z# _- y' H
]2 |  D6 l% X4 X' X" B0 }+ [

  x1 K9 M9 h# d' X7 Qpatches-own3 b: c1 D0 [( A
[
5 y( ~- R% {0 U& ^" ]3 R9 q. p  intersection?   ;; true if the patch is at the intersection of two roads
6 g' A; z; p& e9 d  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
; `3 i7 d& h1 S0 O                  ;; false for a non-intersection patches.
% N& `, W/ j6 M- ~* Y: n5 m  my-row          ;; the row of the intersection counting from the upper left corner of the+ m$ H/ m% U7 h* Y3 r. ]* G
                  ;; world.  -1 for non-intersection patches.
8 V$ h0 i7 @& J4 J2 e( [: m' O1 b  my-column       ;; the column of the intersection counting from the upper left corner of the
' R7 [/ u, o' z) ?                  ;; world.  -1 for non-intersection patches.
, L  b5 ~2 G$ u8 ~; {  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.# p! J5 W- V9 c( P7 M+ U, A
  auto?           ;; whether or not this intersection will switch automatically.
  O  j2 j1 p# C. y3 ^                  ;; false for non-intersection patches.
1 z! l' k8 I! O( {+ A1 b2 |& C1 i6 y]# b7 \; s1 A7 K1 d! S

) q! @% D/ I& C: {  u: x2 x+ B9 E7 c2 I: b5 b5 H
;;;;;;;;;;;;;;;;;;;;;;
) B, f6 M8 k3 D2 B0 ?4 c/ Y4 n;; Setup Procedures ;;. q0 [* _1 s9 Z% y) {
;;;;;;;;;;;;;;;;;;;;;;
, ], S7 p' s4 F5 y* B' \& N6 w% ?# F' r" ~
;; Initialize the display by giving the global and patch variables initial values.) ~& |3 k& t# H- S4 _% p
;; Create num-cars of turtles if there are enough road patches for one turtle to
& r3 H# |+ o& L8 p;; be created per road patch. Set up the plots.
1 ^6 O$ L2 h* u4 Q2 Kto setup1 s0 a. r$ T6 B  D! j7 a# [* o4 d+ V
  ca
, J( p# z. t' ^8 Z# D7 Q9 d# V  setup-globals) ^& x: x0 q% O# q. A# T3 b7 k

0 q" L# O1 h" J9 G, G* N& K  ;; First we ask the patches to draw themselves and set up a few variables
, t4 E; N: ~) K' M  setup-patches
+ \! `: h- [% f# O+ C4 K) u  make-current one-of intersections- z$ e8 T5 J$ d2 _( U
  label-current
. @6 m2 u9 B$ y" t  |: E
  W) I' t& s$ H* x  set-default-shape turtles "car"$ [. }5 @. T$ ^3 K8 `/ ^

4 y5 j" i; U( Y3 m+ Z+ w& J  if (num-cars > count roads)- W2 A7 T2 J3 A. J7 R
  [
* r9 n; j. }; d1 R) N; f8 Y5 M    user-message (word "There are too many cars for the amount of "2 @; a! r9 y7 R1 U4 r* f# C7 q
                       "road.  Either increase the amount of roads "
9 I$ @1 O) \( P. m+ ]3 ?# I& j  |                       "by increasing the GRID-SIZE-X or "
7 K2 Z! X" g* ^! r                       "GRID-SIZE-Y sliders, or decrease the "" f+ y6 s5 N3 Q2 S2 F
                       "number of cars by lowering the NUMBER slider.\n"3 S: B7 j5 G3 T; ]5 Q# `
                       "The setup has stopped.")! q' H) t% u$ r; f/ C7 j
    stop
# b# Z: P" @. r2 \6 W; f- V  ]6 X7 a4 V2 L" J. R1 |% U

3 B6 I4 B& k5 u9 U, x, T! N  z. s( ^0 n  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color8 U! j5 `  j3 k( s& U9 k# H
  crt num-cars
1 }" f+ z& s: X8 E; P; Q( U  [6 X* ^6 V: a! e
    setup-cars$ J1 P: f. W3 Y+ j
    set-car-color
1 }6 K$ Y( A9 Y. u# E: x1 L: n    record-data
5 k! R- y, b$ Z7 l  ?5 N  ]. `/ k6 [0 [% m
$ {/ S1 w7 o, C) D/ {- I+ u
  ;; give the turtles an initial speed6 P4 V% D3 G/ x
  ask turtles [ set-car-speed ]# J! f: w' l' [8 k; p7 r
6 ~- C+ y4 e& F) a0 _" V
  reset-ticks! ~6 y; H6 ]2 T: |" `
end
/ p. W9 x0 O. E; r4 U$ J# V# L  j$ V. x, w+ Q: @' U  d
;; Initialize the global variables to appropriate values
- q+ n5 i: V& Z5 v# Bto setup-globals
# n5 p) T3 M9 [* Y8 t) J  set current-light nobody ;; just for now, since there are no lights yet  K- L9 U6 C7 u- N" D9 b
  set phase 0# Y" I9 p5 _/ i* R
  set num-cars-stopped 0! E5 U& q& ]) p  _: b: S6 V* c7 r
  set grid-x-inc world-width / grid-size-x0 L% x& t& k! n9 t$ i% X; a
  set grid-y-inc world-height / grid-size-y, t5 ^3 u* F6 {$ M, T
, g1 W# C& f5 D7 t3 N) f
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary8 L# l' w1 f: ~  z, l3 @
  set acceleration 0.099! B0 s- b/ A" o
end
8 ^' b4 t4 ?: c3 c) D6 Z% x0 ^" Y5 [# C, i* s9 y
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,3 o3 i+ y* j3 ?& N; L1 v. M
;; and initialize the traffic lights to one setting0 F5 d4 `' b$ Q- O# T  `! d4 O
to setup-patches
% B' H: t% t- Z) Y7 }1 Z  ;; initialize the patch-owned variables and color the patches to a base-color3 R6 y* \6 g2 ?9 Z. [. h" P' r
  ask patches/ o; x- k7 r) @7 o  _. L( k3 D
  [
4 ^6 J! K9 U* n    set intersection? false+ P: q& T: Z0 K2 d0 C6 B% }
    set auto? false
0 w- f1 |+ m8 S, R! l% Z  }; D- o    set green-light-up? true
8 e6 t# o% w) n. J    set my-row -1) X9 e/ {# `/ N$ n: e. Z
    set my-column -1$ a8 h% p8 {, V* }
    set my-phase -1$ r1 {+ X4 M- }( t: N# k! g1 E; ?
    set pcolor brown + 3) _5 @* ^6 ]" U3 d1 l0 H8 }/ L3 D
  ]& O. X8 y% \$ e- V, M
+ r- B2 Q8 N" o  K- N) C
  ;; initialize the global variables that hold patch agentsets
. P7 D# V- L, ]: d& |! z0 t1 B5 O. Y  set roads patches with" p$ o7 ], b8 \9 D% s$ ?) i
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
' |# m3 K- z: {5 @6 N5 h    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; T+ N* I3 k8 Q/ W4 e
  set intersections roads with
6 D/ w9 Y: c  E2 p1 m    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
8 k4 Y7 j( _. \6 s. ^    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) p# p9 R, y5 I3 y. t% u& u: W4 }' z8 X' B. e, ?8 }; A4 J
  ask roads [ set pcolor white ]8 \: k$ _% f( n7 f( ]
    setup-intersections2 [7 c& r: [9 \! K' M
end
/ {' |/ q) j. `- J其中定义道路的句子,如下所示,是什么意思啊?
; L$ E: E2 Q) H set roads patches with4 J5 X% @5 N# e& X) |" \7 ?- }
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- a2 w4 D. n% Q. v
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; }4 k: Y$ G/ m9 Z, I
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, 2026-3-12 16:49 , Processed in 0.016531 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