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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。
4 _; j1 Z& H; I! S3 \$ {, B8 fnetlogo自带的social science--traffic grid这一例子当中,
% j: ^0 o7 i0 X. |: X, [+ H1 }! tglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
) R5 k# x9 b- ^ grid-y-inc ;; the amount of patches in between two roads in the y direction3 T/ j- ~, B9 C! X [$ r
acceleration ;; the constant that controls how much a car speeds up or slows down by if! I0 M3 ]! y( a4 \& S0 b/ d9 `4 s
;; it is to accelerate or decelerate" O2 Z6 _, T. E- V9 H6 x* l
phase ;; keeps track of the phase" j9 A. [ u0 h( d# |& i
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
9 u. t- w% N6 J9 |8 r current-light ;; the currently selected light
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& S0 k1 o8 \- K0 Y4 m2 D ;; patch agentsets8 o( I! e2 m7 H) t, b9 R
intersections ;; agentset containing the patches that are intersections
* T0 m& J" N! H* y* x6 \ roads ;; agentset containing the patches that are roads: K; x1 o8 m5 S# f* t, e( W
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turtles-own' u+ `# c0 O% G4 @& s
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speed ;; the speed of the turtle7 f/ N! Y7 _6 {" l- r9 l
up-car? ;; true if the turtle moves downwards and false if it moves to the right7 j9 \! l" \# ?$ G1 D" h) I
wait-time ;; the amount of time since the last time a turtle has moved6 R }- a& N3 Y K6 g
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4 x7 q8 J7 b5 u- A$ `3 fpatches-own
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* d: s. V0 a6 v2 @% x intersection? ;; true if the patch is at the intersection of two roads5 I" G# o5 R# y ]* S3 X9 ]9 \9 J" b
green-light-up? ;; true if the green light is above the intersection. otherwise, false.1 L& Z9 o- ?3 r
;; false for a non-intersection patches.0 b( \& V' @4 o' U- c
my-row ;; the row of the intersection counting from the upper left corner of the
" ?1 t$ n) z4 f: T ;; world. -1 for non-intersection patches.# x" ^) [$ M9 |, [! D
my-column ;; the column of the intersection counting from the upper left corner of the" F8 W3 P: I" q8 e" @0 i& h! ^, f: y
;; world. -1 for non-intersection patches.
2 F i8 U& k0 Q% M( E9 `0 ~/ ` my-phase ;; the phase for the intersection. -1 for non-intersection patches.
, [& u S; N/ d5 Z) a4 a auto? ;; whether or not this intersection will switch automatically.
@; E5 _: v! d2 x ;; false for non-intersection patches.1 G* J6 M! h' V
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;;;;;;;;;;;;;;;;;;;;;;
% ?8 \0 [' H; w# V;; Setup Procedures ;;
2 Z) }6 v. p0 @$ z L9 s' W;;;;;;;;;;;;;;;;;;;;;;3 h' m# G8 c/ y' s
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;; Initialize the display by giving the global and patch variables initial values.
" l9 c) |, |5 J! y8 C/ P3 ^2 z" W6 L;; Create num-cars of turtles if there are enough road patches for one turtle to- z3 m: C& u9 G S9 d
;; be created per road patch. Set up the plots.# x5 u) }' [2 z/ K. T6 d
to setup
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- f0 a+ J- j! W! w5 g* ?6 \& y setup-globals& d& }+ N* E, Y; m" X' s Q. X' R0 {
9 {* m& m3 w5 o2 Q* U6 ~5 w9 ] ;; First we ask the patches to draw themselves and set up a few variables
- D8 t: N; Y7 O6 |5 V setup-patches
G' x! x C9 i make-current one-of intersections
1 G4 r* a, V. ?! y* c/ w i' ] label-current
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& x5 w3 v9 S. X" X, F% l set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "/ L# y1 S4 J! h" a' T9 K: ^* I
"road. Either increase the amount of roads "
) V8 l: F: g, c# _* ~- H "by increasing the GRID-SIZE-X or ", J% t7 d- K7 Q K
"GRID-SIZE-Y sliders, or decrease the "
5 q4 p! W' |. O0 Y! H "number of cars by lowering the NUMBER slider.\n"# h/ ?6 }; V. s2 e& {/ |' F3 R
"The setup has stopped.")4 `# z0 l* h; A- |' e
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color% `; N, Z$ }: W6 L5 J3 j
crt num-cars
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setup-cars B, { W. B) F& Y4 a/ J9 U
set-car-color
+ u# |& x0 Y4 Y+ ? record-data
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0 G$ { W8 w. @; x% W ;; give the turtles an initial speed
* d! h* ?* d1 N9 z* f8 `" Y ask turtles [ set-car-speed ]$ G% b7 i; ^; i# D- p: O/ n
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reset-ticks
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;; Initialize the global variables to appropriate values3 f8 I7 n( M( L
to setup-globals3 V8 A/ P9 U1 O7 _
set current-light nobody ;; just for now, since there are no lights yet
0 g; S& c d* [* M" T; z3 T; g set phase 0
( n- [9 V6 O! u set num-cars-stopped 0& Y3 A) ~3 U3 K2 a) T3 a
set grid-x-inc world-width / grid-size-x5 r1 O- j. H$ ?8 [! K2 W& H. c& B1 k
set grid-y-inc world-height / grid-size-y5 B* C2 i- P" b3 v. I
/ B# ?# }1 F6 q1 R/ @ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary0 B& e4 [8 j( ~! g( D
set acceleration 0.0998 r4 [- E5 x8 L9 }- p' I- W* f
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,% f+ Q) Q+ `$ r% E7 G; B5 B
;; and initialize the traffic lights to one setting# ~$ t3 @6 z% c0 ?( X A5 c
to setup-patches
& ^- U5 B/ J' P$ E2 P. G8 k8 i5 h ;; initialize the patch-owned variables and color the patches to a base-color
& G) A" M/ u* b: ~+ \; b- G o ask patches/ t- h- E1 ~! p* I* b
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set intersection? false
$ P% x( O3 P9 p! X2 x& j* p. p# |( } set auto? false" |( ]/ k: \1 f* E: ^) @
set green-light-up? true: k$ p! b# L" J9 K/ }* R
set my-row -18 b1 V, ` d9 O% D, D c, _
set my-column -1; o" T& q9 W& ]' K: N! J% Q
set my-phase -1
9 j) m- @3 Q% `$ |- w! B" V set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets6 x" B7 T i) `2 p9 k; D
set roads patches with
8 n& q( K+ z# M- I$ e [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 p2 e- T- Z$ G$ |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# D5 M8 a/ U/ E$ @. z! n, p9 j
set intersections roads with: O. K5 o' X0 M% q' g C
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
- ]- ~! o& E: e5 }2 B$ n4 S* _, K (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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2 Z. ^$ m y& B0 T! T8 e2 _6 l ask roads [ set pcolor white ]6 e7 J' H+ h. r+ L$ q( B9 c
setup-intersections! a8 ?8 d; e& z' w- f6 B
end
! v4 M: \; L7 w: m% @7 k其中定义道路的句子,如下所示,是什么意思啊?
$ q# p- C% @$ [- x4 O set roads patches with; z" c, \9 k }% p( i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 P! v: Z( _4 L% G: ^
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 a* v8 b' S; l% p* f4 J: @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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