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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。
( k6 v' c/ S) a Cnetlogo自带的social science--traffic grid这一例子当中,( k+ R) \0 D8 S& K
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grid-x-inc ;; the amount of patches in between two roads in the x direction" ^; n3 L1 D) Z. J" P: K
grid-y-inc ;; the amount of patches in between two roads in the y direction; B. M- `5 c6 h8 [- T1 s1 N
acceleration ;; the constant that controls how much a car speeds up or slows down by if
4 d8 t) B0 Y# H, J$ U+ C ;; it is to accelerate or decelerate6 t, l% n, w Y! y' A7 R" ~- R
phase ;; keeps track of the phase' F1 B* {! f$ O6 r
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure! z8 ]+ [( d/ E6 K, |% q/ N0 F% f
current-light ;; the currently selected light! L/ k, ^+ k$ Y p4 n$ i
2 @0 h2 p& s% o/ t ;; patch agentsets" n0 G. t6 {8 H, W) J3 B
intersections ;; agentset containing the patches that are intersections, S6 G9 k. O& F
roads ;; agentset containing the patches that are roads
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# ?+ l$ m% n7 e; z* ?1 _" Dturtles-own% D- J- h) W4 D u
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7 |3 |$ j* F/ H* j" B0 \# W- { speed ;; the speed of the turtle* e9 C3 ^. w; K6 [) I
up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 \0 M, f, H ^' C wait-time ;; the amount of time since the last time a turtle has moved
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, a4 v5 b+ b2 T( T! p; ypatches-own
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intersection? ;; true if the patch is at the intersection of two roads
, j2 R3 ^+ ] Z4 s/ i2 L# _( R: G( f green-light-up? ;; true if the green light is above the intersection. otherwise, false.
1 [: @6 N# v m) j$ {7 a ;; false for a non-intersection patches.
' O) k1 ]- o# F; d5 d% C2 y my-row ;; the row of the intersection counting from the upper left corner of the
9 E2 u' E% h& t9 @6 g5 U ;; world. -1 for non-intersection patches.
5 F# \. a+ H, ?8 D& e" r- L# E my-column ;; the column of the intersection counting from the upper left corner of the
) b4 H( c) Y. M! W, C ] ;; world. -1 for non-intersection patches.
[- q7 R! g5 m/ S2 x9 m& ]0 ?) \5 p my-phase ;; the phase for the intersection. -1 for non-intersection patches.
+ n! w* K) T; K+ | ]) w2 P auto? ;; whether or not this intersection will switch automatically.: f c1 D! _ x5 g8 v+ d
;; false for non-intersection patches.
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c- P- h" n% p: t8 w;;;;;;;;;;;;;;;;;;;;;;* R2 Z' e. N. Q9 t( n* p! E
;; Setup Procedures ;;
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. \+ ^9 }" @4 |5 L;; Initialize the display by giving the global and patch variables initial values.
! F) N$ t R* V;; Create num-cars of turtles if there are enough road patches for one turtle to
' H6 v# N$ }0 S( _6 O9 m;; be created per road patch. Set up the plots.8 {! ~3 f- r; X1 T
to setup0 s1 q& o% h" U6 {8 o4 S) t+ N
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setup-globals* U. z; p( b: \ \7 A1 E; ~# g
+ B) b8 a1 N) X ;; First we ask the patches to draw themselves and set up a few variables3 t5 H# @+ C3 { N/ Q" j; d. o
setup-patches
$ A0 t9 }3 j: K" y make-current one-of intersections
; D5 Q* `) J! T4 I% w" B$ N label-current
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/ a2 ?: I! c4 K) }/ c7 B) N set-default-shape turtles "car"# c! L& k4 S0 @2 u, L, |- M1 Y0 q
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if (num-cars > count roads), H7 Q5 s% b1 @1 L* l) _
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2 K( {: G- N* n$ j: p |) {. \: O user-message (word "There are too many cars for the amount of ") T S& E8 E6 q3 U
"road. Either increase the amount of roads "
% g7 F, P9 L8 F "by increasing the GRID-SIZE-X or "# ^. s& O1 E0 _5 T6 }& u! z
"GRID-SIZE-Y sliders, or decrease the "! f, V& B3 q! @* g+ v6 R# ?
"number of cars by lowering the NUMBER slider.\n"
9 m6 Q, Q( q4 F) z+ I0 L. \: P: ^/ [ "The setup has stopped.")9 Y- o1 A3 E6 @, F% u! S* P
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
* }) }" O/ z8 ]- e" _ crt num-cars! `5 D& `& B4 y( X9 N
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setup-cars5 D- \& B5 u& k. b
set-car-color, N; O$ [% A/ X. R: U3 D6 S
record-data
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/ x/ k E8 |/ L7 Q6 K/ h ;; give the turtles an initial speed
! B/ U, l3 U8 [8 `, ] ask turtles [ set-car-speed ]7 [- c$ B0 B2 ^
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reset-ticks" r. K0 r0 G% j" w+ V4 t7 y# q
end
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; e" w# U/ U4 A. `+ ]! d;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet0 o7 r' g- H( |( e6 } l
set phase 0' N7 @0 i+ f- B" i( `" E! s# h
set num-cars-stopped 0
& g) V. \; a& w4 l- f$ K set grid-x-inc world-width / grid-size-x* L$ Y9 O* ~7 Y9 @& j( O
set grid-y-inc world-height / grid-size-y
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# H- }# o* d& t+ o0 m9 @ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary; A9 G; I0 g5 E
set acceleration 0.099 d0 r! R5 z' Y J
end
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7 Y! u {8 T+ V* m4 j/ E;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
g# H5 r8 i5 W7 V;; and initialize the traffic lights to one setting& l4 b5 S' S& I* V' ?( d; g' t+ T ~" E5 \
to setup-patches- v" r6 j1 |& h& X& U
;; initialize the patch-owned variables and color the patches to a base-color
0 Q; P- ~4 ~2 l* Q: h ask patches* p' \8 k6 E- b3 N$ i
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5 I5 d8 l# ]* f4 O set intersection? false
6 N4 A Y2 h1 W2 Y Z set auto? false
5 E, Y1 z) d$ [2 ~ set green-light-up? true3 t( ]! o: Y' f# ]2 t
set my-row -1
* @8 W# l9 P+ @4 d, U set my-column -1
+ h) D) y0 n) M" G/ i% c, F$ q set my-phase -1
" E: T! }+ z! I* R set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
3 h3 c" X4 X; c8 m( }$ E set roads patches with
2 p( m- p+ m% k5 d2 R4 h2 b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 G0 T5 c8 W& c3 x4 B (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 Z; f: s( V/ c1 s, i" |1 u
set intersections roads with. j w" }! L) Q) H# a$ S9 ?% c6 @
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
8 o9 K3 ~/ L( ]; O6 n3 A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 r! H8 {7 ?: k" Q
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ask roads [ set pcolor white ]
7 n6 L6 V1 g* u7 E setup-intersections& ^: I; d. V+ f E- g3 F3 q
end
# J* G+ w+ e U其中定义道路的句子,如下所示,是什么意思啊?# p! q8 `0 g- s; a8 B; @2 M7 s0 R
set roads patches with
8 g, h; h& f! G+ H' d' m) T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& N: H7 x% _/ G# c) S9 {+ ?
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, f5 E7 h, r, f! 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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