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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。+ P9 o5 i2 F! P" q
netlogo自带的social science--traffic grid这一例子当中,& Z9 E3 G0 |- m: { `
globals# d% R# {" n: g
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1 E& {) E1 s: @" X2 ~ grid-x-inc ;; the amount of patches in between two roads in the x direction+ V I0 U8 f/ F2 T
grid-y-inc ;; the amount of patches in between two roads in the y direction
4 j: w* v0 ~/ g. S acceleration ;; the constant that controls how much a car speeds up or slows down by if
' x7 [ G# o" F" O" e. S3 w ;; it is to accelerate or decelerate E' f# U* P: _( t
phase ;; keeps track of the phase0 T; S5 G2 _4 B
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
}" @1 W* G! K current-light ;; the currently selected light$ G& _6 ]5 f% _2 O0 }
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;; patch agentsets
4 y' h" ^; M% z) @. T intersections ;; agentset containing the patches that are intersections; q# j9 p ~5 l2 C. P0 W5 C
roads ;; agentset containing the patches that are roads
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# e& e. P7 c& B: \/ {% Oturtles-own
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speed ;; the speed of the turtle
$ b; _( M# n U7 S$ ~+ }- X up-car? ;; true if the turtle moves downwards and false if it moves to the right
0 h" p) X& d1 s7 N2 S: J" o: x wait-time ;; the amount of time since the last time a turtle has moved
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patches-own% ^3 ~4 P2 C+ S T' g% H
[
0 S: H: W. {" ~8 \ W. k. ^. { intersection? ;; true if the patch is at the intersection of two roads
: @# ?! z8 k/ _7 h! i' V f5 A7 d& W green-light-up? ;; true if the green light is above the intersection. otherwise, false.
& X3 l) G% c u Y) c ;; false for a non-intersection patches.
9 D _$ J4 z; d5 T' S; B my-row ;; the row of the intersection counting from the upper left corner of the; X5 ?: o( B! d" R2 X L
;; world. -1 for non-intersection patches.2 E) U: Y1 b# U" W6 j$ A, V
my-column ;; the column of the intersection counting from the upper left corner of the( ?. ]& H2 D* g$ Z, Q& g
;; world. -1 for non-intersection patches.
: D/ S: q V3 S3 o4 z1 x1 D0 x my-phase ;; the phase for the intersection. -1 for non-intersection patches.
& h' {2 s; S" h9 g/ d auto? ;; whether or not this intersection will switch automatically.
3 Z A- V$ m/ Z" J ;; false for non-intersection patches.
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: i- t# O" }; }; R! T o% j; k;;;;;;;;;;;;;;;;;;;;;;
: N) e+ `$ X( }# ~5 H/ |;; Setup Procedures ;;0 q: n: s* Q! Z" ~0 V' l
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.8 n4 a2 F* ~: D8 K1 o( d0 [& D
;; Create num-cars of turtles if there are enough road patches for one turtle to
4 y, u/ U9 i# r' d# h, n;; be created per road patch. Set up the plots.
8 d6 h7 f9 X d9 v2 I3 S' N' z( _ wto setup
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' ~; }7 _2 r+ O) m0 H" p setup-globals Q& M u# m) Z% q$ H2 ~+ P- M
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;; First we ask the patches to draw themselves and set up a few variables. h2 s/ ]# F. o6 N e9 A
setup-patches" k) r1 @9 C( V1 `) t# U; B, T- C4 y& w
make-current one-of intersections- `- h+ ~, o9 W6 f! E
label-current
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3 S, }3 Y% X- {& x+ d; F set-default-shape turtles "car"2 U7 i3 z6 Z. c
; ? D. s& d& t0 ^ if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
5 B6 G5 d; Y. @0 N "road. Either increase the amount of roads "
( M! p, Q2 h& J& i9 F. t- n1 O "by increasing the GRID-SIZE-X or "0 O6 Y* l3 \. s, }) A o7 c
"GRID-SIZE-Y sliders, or decrease the "- w2 j$ I6 x: ~, k# L% X+ t( r
"number of cars by lowering the NUMBER slider.\n"
6 |/ V* F& J, j: ?( u ?) y "The setup has stopped.")
% k6 L* D7 b3 t& K stop: c4 H2 J+ U7 D8 X0 D
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 n# g8 K3 B0 |. f" \4 f crt num-cars
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# e5 w" K; B- I+ w0 B) {" _1 z setup-cars6 ^4 r, E( @ W, D3 d# e. u0 N
set-car-color! Q h# K, H) E2 O- r
record-data
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;; give the turtles an initial speed
2 Q$ z, |3 X5 B" _: {) Y( C ask turtles [ set-car-speed ]1 W7 e' K+ ^# |
2 P. f! D# G- _ D; f! q/ h$ q reset-ticks1 I0 k3 U$ [. y; m6 T7 R
end
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;; Initialize the global variables to appropriate values
: J8 ]( y% `$ Fto setup-globals/ ]% n. B1 y( [- J! F% g' v J- y
set current-light nobody ;; just for now, since there are no lights yet5 s2 E: C4 w9 p, z
set phase 0
2 q5 {# m" `8 u$ r set num-cars-stopped 0. K/ b* V. X% I
set grid-x-inc world-width / grid-size-x0 Z- ?- e! [( n; c
set grid-y-inc world-height / grid-size-y; t; e/ V N1 V7 S. ]
8 F+ w+ E6 e2 ? ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
! k* S+ s# r" w4 j3 @ set acceleration 0.099
% l3 C: s, E- |end
0 n, o& x0 V3 {
- y5 d4 I0 }3 Q;; Make the patches have appropriate colors, set up the roads and intersections agentsets,' {8 K- N7 Y% f5 i9 R
;; and initialize the traffic lights to one setting0 ], f, o' v! ? f$ F
to setup-patches3 M* n7 i+ G! u4 A) e
;; initialize the patch-owned variables and color the patches to a base-color* e4 N) u$ ?9 ]( V
ask patches3 r* \. W3 b; T+ k0 ~$ R, Y" ^
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$ t# ~! s1 Z( ]; p! Y set intersection? false
- ?; ~3 ]3 p, F- r+ x0 a set auto? false" z$ N1 T3 n( X& ?7 y
set green-light-up? true' J3 @3 a7 A2 V; ^ y
set my-row -1# m, |' X' }8 n) Y( x' i
set my-column -1
8 F* i5 l5 C; t' ~ set my-phase -1/ w2 Z9 Q5 e4 R# m' s
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets$ z& A& i' z: j% T+ D
set roads patches with
6 P/ ]6 F8 ]& ~+ R% ?# Y9 D [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
' j% M) u, q t5 u7 ~. c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- @7 P& N3 i, u W/ S' E9 s4 k' m
set intersections roads with
' r8 s: l, A, j! W7 i [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( i) ^" o3 X) K4 E1 p( c
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& \" {. u, J) O9 x' x- ?
, D% O0 [/ L/ J( n S* r2 q5 E ask roads [ set pcolor white ]
% h& L; V% B e4 l; G/ p setup-intersections2 _6 d% s. h3 x5 c/ p8 g
end
; w, p0 ~/ C3 y0 _/ [0 H其中定义道路的句子,如下所示,是什么意思啊?' ~& l) t7 X$ C/ w
set roads patches with: Q: N% W: k1 K* U" t! E# h
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# c$ G5 J- P/ o3 j: L (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 w. H( e+ O2 m# X3 V3 j% K5 [' |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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