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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。
& k9 `5 g. M7 O2 o l; rnetlogo自带的social science--traffic grid这一例子当中,; R9 \$ U) G. I4 m8 M, p- N2 \
globals$ J+ r; p. A: G: |$ l
[
. T2 ^9 {; L$ h( }5 F: m/ l4 \ grid-x-inc ;; the amount of patches in between two roads in the x direction
0 s+ {) `& G! { grid-y-inc ;; the amount of patches in between two roads in the y direction$ C6 l/ _4 F' W- [$ L2 \
acceleration ;; the constant that controls how much a car speeds up or slows down by if
" {% ^5 M, a T' N, |$ W ;; it is to accelerate or decelerate
- v6 O+ M1 r& X6 D7 u phase ;; keeps track of the phase
6 G5 a$ D' y a. D1 g+ g. W num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
& S* B- X T+ o current-light ;; the currently selected light. T- |" M3 R# y
, h, o; N( o W3 B- S3 M ;; patch agentsets, A$ H! n' }- k a$ j7 `5 V
intersections ;; agentset containing the patches that are intersections3 w' [6 R k& x' m- g g1 S! Y
roads ;; agentset containing the patches that are roads6 K" n* U* [8 M; h' ]
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turtles-own
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* e; K) @' C, }8 ` speed ;; the speed of the turtle
2 j6 c6 ?6 }, k% H1 F up-car? ;; true if the turtle moves downwards and false if it moves to the right
6 C+ E" `$ a) h( e wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads1 N! b, ]6 Q9 x2 b0 D$ I
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
5 [2 ~! ?8 } y7 |7 W9 b: A' s ;; false for a non-intersection patches.
4 O6 E: h* Q) h/ ?9 F2 @# Y my-row ;; the row of the intersection counting from the upper left corner of the
* c: n+ `, H! B+ H ;; world. -1 for non-intersection patches.
x( M# a& W4 t6 Y z% V4 W* K% ^8 g, t my-column ;; the column of the intersection counting from the upper left corner of the# Y n' ~- {# C: u3 W5 n
;; world. -1 for non-intersection patches.0 d2 M$ ]7 K. \8 D& e
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
i: R( }' {) Z% h auto? ;; whether or not this intersection will switch automatically.
6 K8 G0 u8 L7 m ;; false for non-intersection patches.! E% o ? w" O' j) R! ^
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8 z1 v, e5 u2 A% F) k& H) J;;;;;;;;;;;;;;;;;;;;;;
; X9 D) s/ Y2 m* ^+ c3 U;; Setup Procedures ;;% L9 b7 [' S2 Z9 r$ L. k
;;;;;;;;;;;;;;;;;;;;;;
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2 L) S* E) j ~& L;; Initialize the display by giving the global and patch variables initial values.
4 D7 B/ R Q2 S& q S, x5 m;; Create num-cars of turtles if there are enough road patches for one turtle to# M; P& Q" H2 i% u8 S! x
;; be created per road patch. Set up the plots.* v. B$ C) p0 t3 ^' @, @" j- U
to setup
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7 h) s/ n/ W1 v# q. h setup-globals. P% ^% A: `4 W8 I+ D9 [
! W% S8 ]2 a$ S$ b9 ^) P ;; First we ask the patches to draw themselves and set up a few variables
: w( }( y( q6 G2 ? setup-patches0 l6 a' d" i5 Q8 b) s4 ?
make-current one-of intersections) X' \( l+ L( L
label-current' K6 ~# G# F B! g! A
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set-default-shape turtles "car"
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) m2 s, d! Q( D1 C4 y8 ? if (num-cars > count roads)8 y' w# ?3 T# Q% ^
[
, B( g) E# @# `, i+ C+ x user-message (word "There are too many cars for the amount of "
+ h8 o8 n* ~% N) ?' w9 X "road. Either increase the amount of roads "
# F1 H/ Q0 s' S4 m9 y6 j0 Z "by increasing the GRID-SIZE-X or "1 g2 @% R9 t# u( W8 g) o
"GRID-SIZE-Y sliders, or decrease the "
8 ^) n; S# C) M. ?# [ "number of cars by lowering the NUMBER slider.\n"
3 f/ J5 k! s$ t- {% z$ b! d; o "The setup has stopped.")
n; s) s5 J9 d0 e( m. D- b9 K stop
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2 w% \6 f" ~2 |7 D' J1 I0 e ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color+ U' j7 V/ J/ R7 ?; i
crt num-cars
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, B5 x [" A1 Z9 ]" O setup-cars4 T* X( x" v$ i
set-car-color
! D" U6 t( w- E record-data( }8 w, k) X" {( W* B- ~0 [1 F. C) v
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;; give the turtles an initial speed
8 P2 [. v5 q, C0 K ask turtles [ set-car-speed ]3 p6 P; X7 E5 w' t
3 C2 p( P. W: M/ H: i5 T' l; f reset-ticks7 ?8 k) x, {% H: n
end
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* {& A8 \, U" o; W+ e9 _+ t;; Initialize the global variables to appropriate values1 [; q$ X0 L" A# i' @5 p
to setup-globals E: o- v& {$ |3 @0 e
set current-light nobody ;; just for now, since there are no lights yet
. u E" Z% p" A6 O' b2 P( l8 } set phase 0
; B: Y F. I' f. x* i" w1 | set num-cars-stopped 0' b' Z/ s: _" c2 c0 F
set grid-x-inc world-width / grid-size-x
) M2 m3 ?+ B/ y& ]1 C9 O6 j# I6 a, C set grid-y-inc world-height / grid-size-y' i& x0 r |3 W# G+ N# H2 N- h) b
- H8 ^$ z8 y7 Q ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
: [! V+ |& q# y* Q" W/ ] set acceleration 0.099
$ T& D6 t" N$ ]; ?" y# ]6 J8 C1 fend. x, K& E, F& r
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 S: a' {- O$ e y+ W;; and initialize the traffic lights to one setting" ^# g! s' W. T: w5 q
to setup-patches
1 B1 h5 L# N& \. N4 ]! h1 H9 b4 ^% v: d% u% ` ;; initialize the patch-owned variables and color the patches to a base-color! _& m* [2 G- e* e% d
ask patches/ D7 G/ R$ {# f8 Y$ C0 G6 m" a
[
% x3 s# d4 `% Q2 G set intersection? false
$ n& ?* Z' S. u$ V8 ]# f( j9 D; e set auto? false3 H5 t9 L( ]/ h% }
set green-light-up? true
4 y2 g8 e g* f set my-row -1
' z( @" s; ]6 a+ t7 d set my-column -16 Y, D: @) ?7 l, {& Q
set my-phase -1, M" M, T8 f: G& F5 J# {2 v# R" [
set pcolor brown + 3
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1 h7 G+ ~+ Z0 i, m- ~' Y+ b ;; initialize the global variables that hold patch agentsets
8 N( O" S: w4 K8 ~* V set roads patches with
0 t: s: P' _6 @* P/ ]1 J. d3 o [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 G& g( z& u8 p/ y
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- A$ C1 H+ x% S" A$ |. [8 s8 l A set intersections roads with
& k: e# Y9 Y& _, _1 I [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! l+ o0 q$ U" X( M( r6 W: U' M3 I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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4 ~4 E6 K1 B8 o' T4 Z7 F ask roads [ set pcolor white ]
8 W5 N( C2 j, ~7 x setup-intersections/ }& V( B& y% J6 m% V1 F6 W& W# c
end
- l) O! Z* x$ Q- b其中定义道路的句子,如下所示,是什么意思啊?
7 _' s; h8 p) K# x6 E set roads patches with
( C1 z4 d# [& w$ L9 X! ]/ [; ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or H5 s5 v# G- p
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ n0 B4 T6 z- g5 V2 g9 Q+ m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? |
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