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: 9292|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。
( T/ R$ K! f2 G0 z: Q2 k& k/ [/ inetlogo自带的social science--traffic grid这一例子当中,
& c) G5 E' @( U$ iglobals- |8 |' @$ `' ]* s1 n- ~
[; J- o& U* F( L; j/ Z
  grid-x-inc               ;; the amount of patches in between two roads in the x direction
7 K( C2 D( O% S% L3 {  grid-y-inc               ;; the amount of patches in between two roads in the y direction
9 C: n, }( l+ b, |! I  acceleration             ;; the constant that controls how much a car speeds up or slows down by if
& ?" P8 N, y. ?1 k0 }; U                           ;; it is to accelerate or decelerate$ t; n1 Q! c1 A" [, ^2 V" i$ z3 d
  phase                    ;; keeps track of the phase2 z* K# R. Q% e5 o2 `2 K
  num-cars-stopped         ;; the number of cars that are stopped during a single pass thru the go procedure  k# |5 R% ^1 N; ?& C. Z
  current-light            ;; the currently selected light
# b9 ]/ `# I4 n+ z0 i6 T3 N
7 _& C5 q$ Z$ U- _# m1 x  ;; patch agentsets
& L* j* @1 `) _  intersections ;; agentset containing the patches that are intersections
* J$ h' Y" G) E$ M  F& H5 v- e( `  roads         ;; agentset containing the patches that are roads. h  @" P" J% @
]
2 C$ B. A" ^5 e4 s1 j! K* C* F6 E6 S& ^/ D4 G' a3 _; \& g0 ^6 y4 ]
turtles-own
, |3 C  g/ x8 E. J3 c( t- l[0 y1 x- x# M0 S, {* J
  speed     ;; the speed of the turtle
7 d! K7 W0 Q/ _: s6 u4 S  up-car?   ;; true if the turtle moves downwards and false if it moves to the right
/ H  I/ k) n; _* a  h  q- J  wait-time ;; the amount of time since the last time a turtle has moved
/ Z# ^: C0 n# k1 H3 l]
4 q+ u' W& ?$ Z% g- y+ `- ^/ \
& Q: L& w3 X$ `+ H/ Q5 D5 qpatches-own
+ `* P1 O' K! e[
* ]% I$ k: _3 ]/ {% X  intersection?   ;; true if the patch is at the intersection of two roads* z" x; A5 |) j+ Y2 m( H5 h& m
  green-light-up? ;; true if the green light is above the intersection.  otherwise, false.
# f# @! v- h+ J" g# g1 d                  ;; false for a non-intersection patches.
/ y2 d1 H" X) `+ @. I4 D  my-row          ;; the row of the intersection counting from the upper left corner of the
- k9 j; U  P4 O/ m* a: E                  ;; world.  -1 for non-intersection patches.; ?$ c" H# i: G/ p1 N4 ?; i; ?& @
  my-column       ;; the column of the intersection counting from the upper left corner of the
9 r( `2 q% [+ k0 ]0 F                  ;; world.  -1 for non-intersection patches.: c% o. m1 Z$ r8 h5 j0 n2 U5 [
  my-phase        ;; the phase for the intersection.  -1 for non-intersection patches.
1 Q& ~1 d- ?# B( _2 U+ K8 v  k  auto?           ;; whether or not this intersection will switch automatically.
& u6 p& A$ @9 P3 {# c                  ;; false for non-intersection patches.# h3 |$ g. a  J. i$ {8 e% P( w
]0 ]; G+ ?) k5 e/ C9 j4 g3 h% w

/ A- w  j" }8 Q- {) Y9 o
& |3 T- Z# k/ _0 K$ z;;;;;;;;;;;;;;;;;;;;;;
& B' C% r7 i1 y: r4 t;; Setup Procedures ;;
; G# O& C; q0 `1 Q; ~/ p" @;;;;;;;;;;;;;;;;;;;;;;* v9 @4 n4 P: o5 [5 w! E
  k0 b" A6 h) S" R, E# c& D# a  r
;; Initialize the display by giving the global and patch variables initial values.
  v& r+ E  N% [7 x* D! B. t;; Create num-cars of turtles if there are enough road patches for one turtle to
8 y% c7 w, r8 U3 f' T: o, M- {;; be created per road patch. Set up the plots.: Y9 [9 p( u& @7 v" |* H7 O
to setup( I2 Y9 @! k' _* M
  ca
0 K6 ~0 ~1 H8 Q" X  setup-globals5 M& P/ ^9 F, j" m
( F/ S& P6 w) e1 e+ X  r2 g
  ;; First we ask the patches to draw themselves and set up a few variables
8 {  i7 r3 M, b9 b2 ~2 `! O5 F  setup-patches7 W) Y# O0 h- c) x( f1 I  z, Y
  make-current one-of intersections; X% q9 s0 p( N# {4 F: E
  label-current& v* i7 {/ G( u& K
0 d( E3 z( n8 S- K2 }
  set-default-shape turtles "car"
8 \! b6 g4 ^% l$ a. q  O3 G2 o  v5 S
  if (num-cars > count roads)
% Y4 V! k6 R2 t" [* Q  [
5 i+ i3 x$ p. V6 P" u9 Z+ o) j) m    user-message (word "There are too many cars for the amount of "
/ C1 P* M: d% a) V% \                       "road.  Either increase the amount of roads "- s. I" X8 O  F* s
                       "by increasing the GRID-SIZE-X or "6 Q: H9 e2 t9 h9 ^9 j; s5 }! j
                       "GRID-SIZE-Y sliders, or decrease the "; y, T1 H4 N' E0 c- P
                       "number of cars by lowering the NUMBER slider.\n"( Z( b' h9 n+ I+ k. w
                       "The setup has stopped.")6 g# G6 P& n! s/ G4 {
    stop" y. r7 r9 Y& g& g$ h( J9 B' L5 d) v
  ]  n3 k6 f$ @8 W8 R& L- O- q6 k
. b' E" m, l: C
  ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
+ {- E' G% b0 }: U6 ?$ @+ d  crt num-cars, H) _; t. _/ Z8 _  ?, s
  [' t/ v% K6 q8 P+ k* i" m/ N
    setup-cars( e) A1 h) e3 L2 r5 O) n9 v
    set-car-color3 d) s$ F3 d1 d" r
    record-data+ p* F& N+ r3 p3 E3 y
  ]' X% z7 R( t4 o; @
2 z2 u( ~5 D5 l# e" C' l
  ;; give the turtles an initial speed
, t+ C. N, _! p9 ^7 `' }, ?5 ~; v$ j  ask turtles [ set-car-speed ]$ M0 V+ [$ U& ^: k

6 ~/ U% d9 a- q1 P# R' m+ K  reset-ticks6 d/ x- }7 m1 f
end
) }6 d: l9 q# U1 _6 Y9 e  M) b& g( Y: }. a6 Y! Z2 x3 b
;; Initialize the global variables to appropriate values
. d: C+ P1 B* C* p/ K( d" @to setup-globals
2 q" X( T7 @" \: K: F5 S) K  a  set current-light nobody ;; just for now, since there are no lights yet* q! ?0 {3 y* y) P5 @
  set phase 01 J9 _. A" b9 y  l- v0 }, Q
  set num-cars-stopped 0& [! G: w; z' A1 \+ x
  set grid-x-inc world-width / grid-size-x# K$ S1 p, H9 h$ K& [
  set grid-y-inc world-height / grid-size-y/ o' z( L0 Q, n' Y

. ^5 d$ K8 n5 g  ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
3 K# E! L3 T3 |7 D3 P  set acceleration 0.099- |- m2 v6 j" R: X
end7 {- G+ G) c8 i5 X& U6 y
9 J& R; T) Q. f, n
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
6 h9 J6 Z/ s4 p;; and initialize the traffic lights to one setting, Z) K6 z1 j$ o
to setup-patches
: o6 ^$ N% B! B6 w" y# R  ;; initialize the patch-owned variables and color the patches to a base-color
6 U8 w/ K, U  H  ask patches
& ]1 }  R3 G; g7 @$ B  [% a5 \% z4 G7 z3 a* m5 @1 `
    set intersection? false* W) D- N5 {! i2 {
    set auto? false
, E1 S4 z/ s) W' n    set green-light-up? true
) ]. x# R0 i. \1 t5 y    set my-row -11 ?6 S2 E% b" X! s# v- t
    set my-column -1
6 C# |: X. W: ^; B/ ?* n    set my-phase -1% f1 I/ @; F0 H. o" w
    set pcolor brown + 3: y% E! ?* X0 g! c0 W
  ]
. _6 b& Y% b" H  s! S. O3 }! [& R& g8 ]& h" G
  ;; initialize the global variables that hold patch agentsets
) S: y' u5 L% ?  set roads patches with. q# h9 s- |) s3 l  K
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 H0 F5 a, [6 e7 c9 c3 m: R. X    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& E" n8 v3 V' x: Y% w% ]
  set intersections roads with
3 U3 i0 j$ V2 X+ z& h# p0 H- S4 O    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and3 ?) O( \1 t( F5 x3 I2 \" [
    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 K. p5 ]7 e6 j. ]' M2 P+ O% m. O" g$ [& R) S
  ask roads [ set pcolor white ]8 }* U% F+ X) l$ r, o) N4 o
    setup-intersections
( l  R7 B' e" I$ U1 {1 gend
! L4 o5 h. `8 c* x( a" M7 A其中定义道路的句子,如下所示,是什么意思啊?7 T3 \0 E/ C# q9 q2 I
set roads patches with7 c7 L/ U* o4 F- ^) Q& J( P$ V% f
    [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: J# Y  o6 t# J! Y    (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' B! E& [  D7 A. 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, 2026-4-8 11:29 , Processed in 0.020582 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