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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。
7 v8 \8 J& o/ f# C+ T6 C" ]netlogo自带的social science--traffic grid这一例子当中,
3 Y4 d2 k* X5 I: R& I$ nglobals' {' y4 L1 U- k( }2 s3 w
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grid-x-inc ;; the amount of patches in between two roads in the x direction
# B7 u0 `- G; H grid-y-inc ;; the amount of patches in between two roads in the y direction
% X6 B8 C1 b4 e9 P8 F acceleration ;; the constant that controls how much a car speeds up or slows down by if) p2 U( o- I7 b% ^
;; it is to accelerate or decelerate
+ g: r* F6 f4 o! t8 n: Q phase ;; keeps track of the phase; R, R+ ]* S0 l. m- B% {% L
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ d$ C, C/ n6 p5 O) d' r
current-light ;; the currently selected light. u# ]5 d& x6 M
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;; patch agentsets1 L/ m7 q$ |* N# L7 |; a
intersections ;; agentset containing the patches that are intersections
8 s, q& @' F5 g roads ;; agentset containing the patches that are roads# G: o' x9 N/ t) ?- T2 W% g
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turtles-own0 q2 M4 A3 c" P/ T. q# C/ F
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( W' n/ V; F) z6 B# x speed ;; the speed of the turtle+ f9 s$ U" U0 p, z5 n. P1 q
up-car? ;; true if the turtle moves downwards and false if it moves to the right* G A0 j& a- q! S. }" L) Z
wait-time ;; the amount of time since the last time a turtle has moved) g: |, ~, N5 i8 m) d
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3 l9 r7 V6 E( r: H( R# W& cpatches-own! w0 F* m9 ]( P" S( A
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3 U( T0 X) s! Q- R2 \ B intersection? ;; true if the patch is at the intersection of two roads B" ^+ s" l# R9 I
green-light-up? ;; true if the green light is above the intersection. otherwise, false.- \, C/ e" J/ l
;; false for a non-intersection patches.
) b8 x! Y7 j; S+ [: a9 o my-row ;; the row of the intersection counting from the upper left corner of the' z$ W& f! @% Y8 M! a4 E2 Z
;; world. -1 for non-intersection patches.
( [. M, q, n2 I8 a2 o, _ my-column ;; the column of the intersection counting from the upper left corner of the( M) p# r& F. n8 @
;; world. -1 for non-intersection patches.
" v& Z! e$ L# p my-phase ;; the phase for the intersection. -1 for non-intersection patches.
6 ^! l, ~! |( Q# `# ?! i auto? ;; whether or not this intersection will switch automatically.
1 n9 s W, @4 C ;; false for non-intersection patches.7 c1 \1 H% @: C! a) n4 S
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+ T' f+ B, j5 a5 E3 U1 M8 u;;;;;;;;;;;;;;;;;;;;;;, Z; B) |8 l/ x/ i5 h
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values. @( v; y$ @; ?( q8 F
;; Create num-cars of turtles if there are enough road patches for one turtle to- Z8 Y- N7 y$ c9 Q& i. @3 B+ z2 E
;; be created per road patch. Set up the plots.% p1 l% e6 b' q- x, J
to setup
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setup-globals* E. T3 e$ r% {) _5 ?3 J8 q9 i
8 k9 t8 N6 A8 z% o% ~' o ;; First we ask the patches to draw themselves and set up a few variables( V% d+ Y3 q- x, J8 Y
setup-patches7 q+ `+ K3 N2 Y
make-current one-of intersections
( i7 j& H- I) d0 e label-current* y/ r$ }+ l: ^0 }! h0 @
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set-default-shape turtles "car"; U" w* o1 B2 V! E- `8 m# |
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if (num-cars > count roads)
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0 p/ ^8 D- b; A& W+ y user-message (word "There are too many cars for the amount of "2 V1 u g2 H# X4 V
"road. Either increase the amount of roads "
, T1 `& `( o# M! X# t: l8 Q$ G7 w "by increasing the GRID-SIZE-X or "
5 V6 J- z" p5 ~5 Z8 ]: o7 g$ J "GRID-SIZE-Y sliders, or decrease the "1 \( `6 a& J1 k% y/ q
"number of cars by lowering the NUMBER slider.\n") _6 H2 @, n- m( X+ k& s
"The setup has stopped.")4 X- `# w5 J4 N! p2 \: M: E
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color- b, k+ X9 H2 R1 O0 r
crt num-cars
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setup-cars* A" ]' Z! U0 p O6 h( S
set-car-color
h; \) o2 u( f record-data
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2 y3 s7 o) o( O ;; give the turtles an initial speed
+ B- Y6 F) l4 L2 I# j% B ask turtles [ set-car-speed ]
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reset-ticks* |: p9 p" }, D( g) T! C/ `
end- n8 `3 i/ R% @8 G& h
! A3 ^# P+ B4 E$ y;; Initialize the global variables to appropriate values9 L3 ^, |+ \ H- E
to setup-globals
1 P, b6 |) X0 I3 w& v8 m set current-light nobody ;; just for now, since there are no lights yet
$ J* P+ X( h; L# j; y, ^* k; e1 c set phase 0
$ ]& t) v; y: K/ x, l! h set num-cars-stopped 03 u+ O3 g* W4 r8 p
set grid-x-inc world-width / grid-size-x
& x8 w$ o" U8 c4 P6 G. \' d set grid-y-inc world-height / grid-size-y
P: W7 S9 M8 [9 E! b' }7 r% x
" ~4 {& n. [& f1 e- [! y ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 i$ B% I3 j- Q* {; V
set acceleration 0.099
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* w. v2 x+ O* R0 P% z7 V;; Make the patches have appropriate colors, set up the roads and intersections agentsets,* ?- }6 |4 M2 X
;; and initialize the traffic lights to one setting% t4 i+ K; \0 M% B
to setup-patches
/ X8 f( c& t5 K% e ;; initialize the patch-owned variables and color the patches to a base-color
) A4 p4 T3 ^+ Q( `% W j. B: v ask patches3 i" ~# o. u; Z: c: H
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* F2 K/ M+ d" ~2 ~, M8 v1 M" n set intersection? false
5 T$ J9 b& @) U$ c( h% @ set auto? false
6 M! [ u; S+ S8 P set green-light-up? true
. s" y4 O W. \% w* s) A! j0 W set my-row -13 A- o \. V2 r% k) a6 T9 L7 u* N
set my-column -1
4 `- M% C5 l. E) y set my-phase -1
# t7 W5 [5 i* I# o7 d2 | set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets% F- f9 c5 K* n1 E2 \3 E
set roads patches with, Y3 i7 u6 B5 A4 L
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 b8 o/ g) U& u6 P& i# H: l* U (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) P7 g! p i, m+ p! W2 q5 H3 Y set intersections roads with
9 ? B% w8 [: g7 M4 `1 Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
. n* E: u. h9 y (floor((pycor + max-pycor) mod grid-y-inc) = 0)], q4 M( A- X- c" E$ T$ k8 ^! q
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ask roads [ set pcolor white ]
1 a# H; [; {" K% _ setup-intersections
6 a ^& W* L) w' T$ ?end
' a8 t! D! C/ E& g其中定义道路的句子,如下所示,是什么意思啊?
D. N8 Z% s K% ?7 Q( G) Y8 E set roads patches with0 p6 ^- n: r0 I+ u' P. q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" y0 q' B: U' t4 h! `' t L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 w( ~$ E# a( K. o+ a6 a7 ~# V
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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