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: 11980|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。
1 W$ p! h7 Y9 G5 w# U) A9 t! u3 xnetlogo自带的social science--traffic grid这一例子当中,# Q9 ^4 \; `- C4 O: O4 j/ p
globals+ _- S2 q+ }1 B4 o6 {) r
[: D, E* L% ^" U' \3 e
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
& t5 {  ]- g% y7 k  grid-y-inc               ;; the amount of patches in between two roads in the y direction8 L7 x, \: i9 b& ^8 Q2 R$ H3 @
  acceleration             ;; the constant that controls how much a car speeds up or slows down by if" o& i/ g& X. s1 ~6 I8 T. o$ b3 I
                           ;; it is to accelerate or decelerate" n* i% y) f) n0 @: i$ N/ X5 i
  phase                    ;; keeps track of the phase
' w7 Y; Z+ K/ t; N2 [4 R  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure8 N) K" G6 b, z% ^
  current-light            ;; the currently selected light
% L% l  n4 e' z8 U9 e* p, q9 j; P1 C. m  d5 Q$ o9 W% |
  ;; patch agentsets
4 W- m6 n+ v: b  intersections ;; agentset containing the patches that are intersections* e* L; e: `& k4 R9 m5 u
  roads         ;; agentset containing the patches that are roads0 W, j3 F3 D4 r0 q5 I) j9 k# H- {1 V
]9 ^$ L5 d. [5 p! u( @

1 {4 @7 e2 d9 ]6 I9 a) `4 J  Aturtles-own
7 D% T7 U  E' g. N% E7 q[; y: J1 B) ]6 H2 s( C+ q
  speed     ;; the speed of the turtle
7 F0 a6 u) d; I3 e  up-car?   ;; true if the turtle moves downwards and false if it moves to the right. }% ~4 g3 l: B2 Q4 b
  wait-time ;; the amount of time since the last time a turtle has moved3 I) z( U/ D$ O! ~" @( I# A1 O
]
3 u5 R0 b+ |5 \# b% u% z1 Q# n* U* I2 X
patches-own
) b2 X$ `# f- S' Z  L' S. P[
- I1 ~+ K3 v. N  l9 }  intersection?   ;; true if the patch is at the intersection of two roads
5 v# E: W# g9 b, p* D( M" l  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
% B$ L, S6 Q3 _7 L9 E                  ;; false for a non-intersection patches.
0 x  p' b" h8 ^6 _6 L- f) T  my-row          ;; the row of the intersection counting from the upper left corner of the
7 G' p8 N4 y4 {7 N! f4 P3 r                  ;; world.  -1 for non-intersection patches.
3 q6 l& g0 o. y: \  my-column       ;; the column of the intersection counting from the upper left corner of the
6 c; B& @0 u- E( Z; W                  ;; world.  -1 for non-intersection patches.7 x5 p, R. z5 R6 S4 o1 |9 A- L3 @
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
: h* W1 Y, ~/ ?1 a6 ]1 p  auto?           ;; whether or not this intersection will switch automatically.
% L6 [- u! v! |. r: T) M                  ;; false for non-intersection patches.
  S$ V! f. E4 g8 _]
# ?0 a# ?6 I* [6 Q4 d3 c
+ @4 x" U; g( D+ e9 a$ n1 {# }2 n% ~; J5 B) \2 M" n7 C$ p1 g* ?; ^
;;;;;;;;;;;;;;;;;;;;;;- n& ?  j" h7 D8 S/ v9 H
;; Setup Procedures ;;9 D& G6 [$ ~$ i' A+ X) q
;;;;;;;;;;;;;;;;;;;;;;
4 `+ z) M( ~1 N2 m2 R/ X
6 E) s4 s. y& r* ]7 a1 s;; Initialize the display by giving the global and patch variables initial values.
# Y# K% |( o6 i# Y;; Create num-cars of turtles if there are enough road patches for one turtle to) |/ V" u) d6 d  y
;; be created per road patch. Set up the plots.- u/ A) M6 K6 q: H
to setup9 o; \( r( v3 q# t" o
  ca
+ R3 r$ d/ J$ o/ _  setup-globals
- W7 v+ a& d: T5 H7 v4 ]5 I+ q( y$ ]2 J! T# |
  ;; First we ask the patches to draw themselves and set up a few variables
) J+ P' k3 _: j, v3 P  setup-patches
/ @' m; H0 |  ?, `7 f, I: g  make-current one-of intersections
" l! v$ s  y5 _0 t7 y! u* T  label-current
; l8 h+ g4 C- ^  M) t
0 k" N% v, ~6 ^7 E  set-default-shape turtles "car"( M7 U, C- _( D: a& E# l* w2 j8 p

) }# L9 U- U5 H/ {/ G; q  if (num-cars > count roads)( n. b. e# v, [; M1 }
  [
" ?) F! d" k2 V8 e6 f8 h% Z# t    user-message (word "There are too many cars for the amount of "5 y' I* `( u+ i" c  N0 K: k
                       "road.  Either increase the amount of roads ", v+ V2 n/ c7 I; m
                       "by increasing the GRID-SIZE-X or "9 f- F) `, a% R) `# X0 x9 S
                       "GRID-SIZE-Y sliders, or decrease the "/ m" \8 b( e& H' ?  c4 m
                       "number of cars by lowering the NUMBER slider.\n"* S& h3 L) Z3 |$ V4 i7 }% C* C
                       "The setup has stopped.")( L% l4 e, \1 A' g
    stop
7 \$ e/ @9 f4 r1 |# l( E  ]! F/ e! H2 Z8 M" }2 ^' v

+ ^/ v7 c0 G6 e3 \  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color# D$ g- g9 d  }% \
  crt num-cars
( G- [- A) p/ v0 `  [
  N& e3 z- t9 Y+ m4 O5 z! w    setup-cars
* T0 }; D) ~# m4 X$ ]* t% C; N+ P$ d0 {  p    set-car-color1 g! W' {6 m8 ~  A5 }% _" {
    record-data& O! c, `3 `0 Z4 w4 |
  ]
1 [  C- l2 |- i6 s$ F9 h
2 X( ?' @* g. G$ X% ?' M5 J  ;; give the turtles an initial speed8 d, x6 `: F+ k, S
  ask turtles [ set-car-speed ]
3 j  G: _- _7 }) Z8 Y1 j- [4 l$ P3 @  k$ n# h" |: R) H) k
  reset-ticks
6 s& o4 Y. ]2 K6 `end
2 E; x  Y4 ]/ A
% b" G2 m" S% Y;; Initialize the global variables to appropriate values. S5 A& }- R: q- ]: c' d2 d* H
to setup-globals
( O0 k# N5 h* f* r  set current-light nobody ;; just for now, since there are no lights yet3 P$ a1 u& n- }( ?2 v4 ?
  set phase 0
4 A' y- m0 c+ O9 b! g! C  set num-cars-stopped 0; H2 ]+ \' t( d7 C. X0 z5 B- ~
  set grid-x-inc world-width / grid-size-x
2 o$ |: L9 A. T! _5 }7 R  set grid-y-inc world-height / grid-size-y
1 ?9 ?$ A. j1 `+ @: w, x3 U4 j5 k: B2 G3 ^* E) B" ]+ B! `+ V
  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary! \/ U) p  S8 Q+ [
  set acceleration 0.099% T" L% v! f) D
end" A1 e3 m& ?9 @: O+ P4 I
# K# d. M1 X: {1 n: `
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
  J/ j! Y; E  l9 T5 F: ~;; and initialize the traffic lights to one setting
# V  r) v# W" B6 p: R  s& wto setup-patches
) S6 [% p0 j& S2 o# C  ;; initialize the patch-owned variables and color the patches to a base-color
% A. U1 D+ ?* Y! K  ask patches
8 P+ o+ u6 T% z3 L  [
. D7 f* @3 e) ^- W$ `    set intersection? false  a+ d3 Z! N  C4 c& d- u
    set auto? false/ u% s% q- C1 _
    set green-light-up? true
2 v" e6 G% o( }& i4 W    set my-row -1, I" d1 z/ [" }- o
    set my-column -1* w/ E! V( d& u) x5 A
    set my-phase -1' p; ^, G  P+ v- O+ K
    set pcolor brown + 3
5 B! U" a. ]. R" V6 Y  ]
. F3 A8 r2 q2 Q1 i
0 O  E0 _5 l: w; V" Y( Z8 M  ;; initialize the global variables that hold patch agentsets
* L6 n! S* q# o/ ]* [2 v& j  set roads patches with! ]5 {# K2 R: z0 V8 ]5 x8 i
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ @5 i% `5 M6 \0 }    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 Q/ Q! G6 I" N; C1 _3 A& Q7 D# h
  set intersections roads with
& k3 w" D+ s0 z+ E" G. I2 ?. }& V+ l    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and7 O7 e: H- ~% S# X
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& D; ?! A( ^9 G' H
: f. ]7 U5 s( G3 v* \  ^  ask roads [ set pcolor white ]
- x& J: M( v! Y: b) J; E% ?    setup-intersections0 ]  n0 A/ q, d) b/ q% ^
end
8 _# @  k2 j1 e2 l9 p+ \* o其中定义道路的句子,如下所示,是什么意思啊?
" f( L# @( G' c- f. q2 J& Y; S set roads patches with5 f3 U8 `# `2 M) n
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ V" q' @$ c! ~+ q6 d: `    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 K. ]$ h5 N+ q' X& [4 P6 A5 O$ A
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, 2026-8-28 02:37 , Processed in 0.016968 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