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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。
) l; g% B2 f) r5 f- ^% h0 n8 k" Hnetlogo自带的social science--traffic grid这一例子当中,! _8 j3 o+ E& l& a O2 B1 G
globals
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. q7 J0 x- z$ e5 h! T; A" a! Q grid-x-inc ;; the amount of patches in between two roads in the x direction* _- y ~! X C5 }& N
grid-y-inc ;; the amount of patches in between two roads in the y direction
3 T* R" f# ?- B# c1 [5 B acceleration ;; the constant that controls how much a car speeds up or slows down by if* n- i+ ?2 B8 u/ w
;; it is to accelerate or decelerate( F( Z" g( N4 [- R( ^. O
phase ;; keeps track of the phase
9 [2 v: u% }7 L# F4 a num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure G6 |% y$ u) H. J0 l! ^' P
current-light ;; the currently selected light
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1 u8 F/ A( ~: S1 [( p/ a ;; patch agentsets( S s# {3 ]7 G
intersections ;; agentset containing the patches that are intersections3 K: p0 @& p$ ]
roads ;; agentset containing the patches that are roads4 g/ j$ G4 ]4 G0 b+ ]7 |
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2 `1 @3 Y$ E3 x; F: @turtles-own9 D; Y, _3 Q$ v9 C
[
# M+ q8 m' A: \ speed ;; the speed of the turtle
; }$ [2 h5 p I) {2 g. y0 l4 u up-car? ;; true if the turtle moves downwards and false if it moves to the right
5 q6 r; Z2 Q9 \$ M4 x$ v9 y6 c; w5 C wait-time ;; the amount of time since the last time a turtle has moved/ |. ^) h" ~& m; V) e6 J3 c, d! } ^
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' z( R p z! h$ Dpatches-own
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intersection? ;; true if the patch is at the intersection of two roads
5 u. ]1 `% E& k u3 a green-light-up? ;; true if the green light is above the intersection. otherwise, false./ k: ?! @6 n- J6 P$ J
;; false for a non-intersection patches.( u8 i& a( ~ E& p) u$ @$ u# N/ r
my-row ;; the row of the intersection counting from the upper left corner of the
' @, ?% H/ A: S5 P$ m9 u ;; world. -1 for non-intersection patches.: I B& p6 h r- y5 }8 A/ n8 }
my-column ;; the column of the intersection counting from the upper left corner of the
! b" M* Z" U" ~" ~' J: y ;; world. -1 for non-intersection patches.
2 {; }9 d. K; @$ G my-phase ;; the phase for the intersection. -1 for non-intersection patches.. T& W; O2 s0 G2 i5 B; n; u
auto? ;; whether or not this intersection will switch automatically.
4 f2 e& k6 T( k% S2 K2 K2 u ;; false for non-intersection patches.6 p$ d% h$ Z9 a
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5 w3 W: l9 x3 C: T* w7 U9 r) J9 g;;;;;;;;;;;;;;;;;;;;;;
8 ~9 J& k/ K( K, P/ o7 e! k;; Setup Procedures ;;4 m, d9 B5 i4 `* L# ]
;;;;;;;;;;;;;;;;;;;;;;* n0 V( U6 z: e( [
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;; Initialize the display by giving the global and patch variables initial values.6 k/ Y, y r& \' i% c
;; Create num-cars of turtles if there are enough road patches for one turtle to$ }* d; r- g9 I3 Z7 X( T5 k3 } x
;; be created per road patch. Set up the plots.
! n! | Q. N9 bto setup' Y* K. L3 E5 l7 r4 P
ca
j0 K0 P% m# a; s- ?& D ? setup-globals M) ]* S& e! i& g. |" `
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;; First we ask the patches to draw themselves and set up a few variables
6 q+ T+ _# v9 C setup-patches% }/ |0 r( W) a- Y1 s
make-current one-of intersections
8 b9 G2 U0 n5 S* L" ^ label-current, h3 a% X' z" S3 T: w
4 R b* n% E: _1 R. a set-default-shape turtles "car"
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if (num-cars > count roads)$ r2 x: n7 x# M$ V1 z
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user-message (word "There are too many cars for the amount of "- Z9 n# e r- C1 k# W3 k6 R. t
"road. Either increase the amount of roads "
$ [% n- a+ j: ~% h0 A "by increasing the GRID-SIZE-X or "
W# I' p2 C' ?& U6 R6 @( C) s "GRID-SIZE-Y sliders, or decrease the "
! [+ S$ ?1 @9 G' o) S& ?0 O. M "number of cars by lowering the NUMBER slider.\n"
; z# B- o# P ?3 N "The setup has stopped.")
/ p! K6 _% @( y; ~ stop5 H3 t/ Z0 q+ M+ {4 M6 q
]
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3 ~7 I: V! A2 R) Q$ ~( y% n ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color& G! r! w1 k: Y: H/ Y, I
crt num-cars, E4 z7 Z1 R/ r' T
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setup-cars: P) d9 d: G; M; E
set-car-color
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;; give the turtles an initial speed8 a* k' `% J0 ~$ g0 H! `# h
ask turtles [ set-car-speed ]
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/ L( q4 d, _# X0 B reset-ticks$ m3 M' W7 W/ V
end
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) ^+ F* L! v/ I0 B;; Initialize the global variables to appropriate values
: Y$ h8 l0 L; W! a# H. v7 ~4 b) }to setup-globals8 T; o3 a$ c; p# \& o
set current-light nobody ;; just for now, since there are no lights yet8 e {2 X; M/ B' \7 u
set phase 0& |) L9 p6 g: m1 k' M6 r
set num-cars-stopped 0
6 p. T" }4 I& I6 t2 g. W set grid-x-inc world-width / grid-size-x$ l2 N9 u7 G' N( W0 g
set grid-y-inc world-height / grid-size-y }* `3 D# `( }/ D
# X/ ?& x0 N4 ?/ G ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary) f3 M. ^. \' P) g, ?
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,* I: B9 S" n3 \
;; and initialize the traffic lights to one setting
) P7 a' p$ ^# h6 ?( v0 F% n" _to setup-patches- R3 t) h6 B1 B7 q- ]2 ~
;; initialize the patch-owned variables and color the patches to a base-color2 A$ W/ ]& y; |6 n' x% l
ask patches
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set intersection? false) U; j. B3 R8 Z: s5 y
set auto? false; a" V& v- {. ^8 s2 V
set green-light-up? true" S* f6 z% f( @3 `* z
set my-row -1( x/ S+ A3 F [9 s6 [
set my-column -1
5 o+ M/ B' V/ L2 C set my-phase -1
2 L! p2 e, } M$ E set pcolor brown + 30 T4 p" z7 f3 K' ~$ D
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;; initialize the global variables that hold patch agentsets: v+ |, v3 D& z- t y1 l
set roads patches with
+ b5 w4 o8 g# Y [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 ?; \1 A' V5 d, S5 |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]" r1 i8 B1 d5 K4 ~. n+ f
set intersections roads with, K5 G% l- J h0 h" I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
$ M: I$ l/ i, u0 a% u (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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4 T; Z7 i4 f& w* w ask roads [ set pcolor white ]
" F& J+ `9 R) O# J, W4 r7 Y setup-intersections3 d7 Q) }7 S& G! N
end6 ~5 w& x% F; F$ P' b, t2 |+ Z
其中定义道路的句子,如下所示,是什么意思啊?/ z1 A6 ?( q4 a e- ]3 C) N
set roads patches with2 E9 z% L8 L7 f# U+ ]
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. x. @$ ^5 l1 J k (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 P, Q0 b# V% `2 q/ C0 x; s6 o0 Z! ?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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