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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。! v% H6 E" z5 J4 r$ w
netlogo自带的social science--traffic grid这一例子当中,$ w1 e& E5 M" t \0 h6 b$ r
globals
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/ y% i+ h9 v5 o- X7 O& Y grid-x-inc ;; the amount of patches in between two roads in the x direction
& i; g9 ]% q6 z% O# Z! l grid-y-inc ;; the amount of patches in between two roads in the y direction
: a2 Q, j/ o# q9 d- Y acceleration ;; the constant that controls how much a car speeds up or slows down by if- l. L. O* S+ _. G5 H
;; it is to accelerate or decelerate) d; k: l: m+ g3 V s, H! J& Z, `( Z
phase ;; keeps track of the phase
; C. Q+ q) W1 I+ N" n& y, t q3 F) i num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure( D" b; ?) r9 P' g, S7 U
current-light ;; the currently selected light- Z' R, P" n$ y) m+ b
: W6 \& l j& b8 ]6 E ?7 U% K$ D ;; patch agentsets' @5 o0 a! f* h9 ^
intersections ;; agentset containing the patches that are intersections0 A) H5 o. U; q+ ?
roads ;; agentset containing the patches that are roads' I* X0 R5 T/ o4 A: r+ d
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. R7 [2 a: i+ Vturtles-own
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speed ;; the speed of the turtle* d# _ p f4 G
up-car? ;; true if the turtle moves downwards and false if it moves to the right
, X! k5 w0 _8 J5 x; r 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 roads
4 U+ y" ~" y# k; y/ _7 S K. e green-light-up? ;; true if the green light is above the intersection. otherwise, false.
3 z' [/ [9 B6 G1 M, _' M9 E6 ?5 o ? ;; false for a non-intersection patches. \5 O! G+ Z% E$ s. O' G
my-row ;; the row of the intersection counting from the upper left corner of the
4 f7 A5 H' {* N7 b5 @ ;; world. -1 for non-intersection patches.
" ?9 g' {9 }- P. J B my-column ;; the column of the intersection counting from the upper left corner of the: S- D9 z7 X/ w- e9 i, L4 n( A
;; world. -1 for non-intersection patches.8 p' k! F7 ^, n( Q4 S/ Y
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
6 j; w+ A. k$ g auto? ;; whether or not this intersection will switch automatically.
* E% A) ~- A: }0 l) ?# `2 g$ h. T ;; false for non-intersection patches.; K9 u0 M) j9 k* h! S. Q
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;;;;;;;;;;;;;;;;;;;;;;: U1 B; W6 s/ P0 M
;; Setup Procedures ;;
, @1 P6 u4 H7 t;;;;;;;;;;;;;;;;;;;;;;. W' ]& k4 n% p
: T) c2 w- ^" e" A2 W6 R" v6 N;; Initialize the display by giving the global and patch variables initial values.
3 O W3 ]9 L4 R2 m" K+ E2 o;; Create num-cars of turtles if there are enough road patches for one turtle to
/ h: O K0 E4 O7 ~;; be created per road patch. Set up the plots.! U' g0 V& l# G9 R. o% {" ^
to setup
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c1 }% i6 L7 a, D setup-globals. \) X- l: b6 X* {1 a- ?5 |: z
$ q8 ]1 t; E' {1 n! j/ m u ;; First we ask the patches to draw themselves and set up a few variables/ {& ^- z. j- W" ~/ ?8 v
setup-patches
( h- P& o6 H ^ S3 W+ W) n make-current one-of intersections7 n$ X+ L) s) `) x- {& p8 o E% J
label-current2 R8 X2 u+ e0 t1 l
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set-default-shape turtles "car"
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; {% F: I+ [: p% Y+ J2 y if (num-cars > count roads)$ V/ Y/ B: X0 @( ^6 x9 |
[
+ k8 I# a7 T s; ^9 Y8 d& p user-message (word "There are too many cars for the amount of "
; w% H; |/ g$ d: D; z "road. Either increase the amount of roads "
, J5 e% B5 [4 ]* g. e" m "by increasing the GRID-SIZE-X or "
% @! i) u g+ c1 O "GRID-SIZE-Y sliders, or decrease the "% z! C- i! f- @- W9 w0 O1 @& O
"number of cars by lowering the NUMBER slider.\n"
# x" W$ Q, g- U8 l3 `& _ "The setup has stopped.")
: k8 L X; E+ W* y+ ^ stop: K+ n: r$ Z2 O( J2 j/ p: E3 b; W
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! m7 o. a/ A% e ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 N9 @8 v( x7 \ crt num-cars
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4 l7 H* a- f2 c- k% Z @ setup-cars6 Y* w( z% v( V3 H l+ g+ m
set-car-color- p! L9 X. n* c s2 v& x
record-data
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;; give the turtles an initial speed6 g5 v( l. A9 A; I* Z0 H
ask turtles [ set-car-speed ]
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reset-ticks
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6 s& H E0 X3 Y! l7 v' ^' b; y) Z;; Initialize the global variables to appropriate values
/ @( I6 l6 A1 C- U7 _to setup-globals
) O: A8 G& A( f+ p set current-light nobody ;; just for now, since there are no lights yet& m! H2 q8 i# y: g) U; \
set phase 04 o' R8 U; ]; C; p
set num-cars-stopped 0( Y8 |; |" g0 \6 [. ]
set grid-x-inc world-width / grid-size-x
6 D% N$ |! ]/ R" u0 h: o' @ set grid-y-inc world-height / grid-size-y
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0 P4 y1 p7 ?' \" t ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
$ D) }" {" i& U# T/ V set acceleration 0.0993 B6 `+ c$ l: i' b! _7 M8 G
end
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7 o% c% l. y: T/ ^. Z( N$ {;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
) F+ M* `8 [3 g) c; } _1 l;; and initialize the traffic lights to one setting" g. s8 A# |7 {6 y9 n9 s7 I! j
to setup-patches; n" M2 Z0 T; S4 h" `
;; initialize the patch-owned variables and color the patches to a base-color
" ], }9 T, p* n; a% M9 l ask patches) B. w1 G% B, h8 Q6 `- n6 J
[
7 _! I) z6 i5 ?$ r9 S6 Z set intersection? false
8 z2 w/ L {3 P6 | set auto? false: r2 |6 t/ q8 k
set green-light-up? true: o" R8 V6 i& F
set my-row -15 k6 p! x* n% U4 e' M, u( H
set my-column -1& T+ X. g$ f# a# L. V0 V' W& {, E* e
set my-phase -1
; G1 A1 B; f5 D9 x set pcolor brown + 3
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+ |- H9 R9 Y6 n4 v: F4 n ;; initialize the global variables that hold patch agentsets
5 j* _, G! ?$ w% H" f* }$ l" C set roads patches with( Z0 \- O$ t6 |5 U5 H
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 @( d7 m, P% L9 G$ g6 p (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' u: G0 @* g9 A! b6 {7 P2 y$ { set intersections roads with
: { f" w8 q) m6 v9 b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 F4 M& a0 Q( W; `
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ], L+ h1 d& d0 o# N3 o9 A, s
setup-intersections
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r [8 t; Q7 K D, f其中定义道路的句子,如下所示,是什么意思啊?8 L. X, \+ r) o$ }2 v, B
set roads patches with
) F" [% \; s2 Q. |2 H [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 y1 z5 i O. W0 i7 _5 s (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 { F% p7 X7 j8 K4 d
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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