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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。' z' P5 ~) K1 l- g. m
netlogo自带的social science--traffic grid这一例子当中,
3 @, O3 K! |7 M4 o* P" iglobals* P, ]& o2 f! x/ k, a: l% ^$ g
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grid-x-inc ;; the amount of patches in between two roads in the x direction
; U# p2 A5 l# S; q8 _5 z grid-y-inc ;; the amount of patches in between two roads in the y direction
0 N% u. \, `4 B acceleration ;; the constant that controls how much a car speeds up or slows down by if+ i7 D8 Q4 d+ ~. k& A8 e" n
;; it is to accelerate or decelerate
2 x6 v8 ]( e) P' O! g+ I phase ;; keeps track of the phase
& p9 l& h& d7 v num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
) g* y2 `0 S; Q9 I0 d& @ current-light ;; the currently selected light
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;; patch agentsets/ `; T. @# b6 [/ j% P; J. \
intersections ;; agentset containing the patches that are intersections
+ }% i& x% P- @, y roads ;; agentset containing the patches that are roads
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6 K+ P, u8 X6 U# t5 ?6 vturtles-own
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- m: i N% L$ d- r [6 S- N speed ;; the speed of the turtle
1 C6 n& N h2 w" Y0 t% x; _; O up-car? ;; true if the turtle moves downwards and false if it moves to the right
! D2 c s% v. o; m& i wait-time ;; the amount of time since the last time a turtle has moved6 `6 q: h9 Z- ?" ~0 n+ x- x
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( d4 c- [$ ^, [$ o2 `% wpatches-own1 ]) ?# d6 t8 Q+ J4 l o( C% F
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intersection? ;; true if the patch is at the intersection of two roads0 [/ y: K( ^+ J. [+ D5 Y
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
8 Q7 E2 Q- P+ z9 W ;; false for a non-intersection patches.6 ?" f/ @( i. m$ L& i4 Q! E
my-row ;; the row of the intersection counting from the upper left corner of the
2 k3 p, u- b) Y8 X+ h5 t& h) _ ;; world. -1 for non-intersection patches.9 \, \ y7 Y& ?5 d$ k& g. u4 w2 W
my-column ;; the column of the intersection counting from the upper left corner of the; r, y7 L; K9 x. M" w4 n, Z2 Y
;; world. -1 for non-intersection patches.4 R2 l) S- g6 M6 D
my-phase ;; the phase for the intersection. -1 for non-intersection patches.% O6 h" j1 @( s7 f# f I! ~! B7 J
auto? ;; whether or not this intersection will switch automatically." I. _) G0 y+ {) k# O
;; false for non-intersection patches. B8 j; T$ }- q# P) R
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4 o3 L1 A/ }9 i! \$ n, j6 @4 E% T;;;;;;;;;;;;;;;;;;;;;;
# S( u% O2 j! T& q;; Setup Procedures ;;! ~' ^; P! p* T: T& d6 P; X1 w. K+ F
;;;;;;;;;;;;;;;;;;;;;;7 ~: d+ w* V; _! `0 c
9 k0 l7 E( H7 f+ O% h3 |3 E" Q- y;; Initialize the display by giving the global and patch variables initial values." ]" q! P' I2 ?1 X8 {
;; Create num-cars of turtles if there are enough road patches for one turtle to# K( k- }0 b& r$ `" m, V$ s
;; be created per road patch. Set up the plots.
! `: b& r! [2 S( v8 m$ a# eto setup- Y {4 K; S) k8 M; _
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables5 p& _2 m3 K. E0 n# K: t* a" ]7 Y
setup-patches
* ~' x+ t. }6 R7 [5 S make-current one-of intersections2 X- ^4 T( M+ M0 B1 Z
label-current
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set-default-shape turtles "car": y/ o. C5 i: J& N; y; D$ p
& D/ ]% W9 r) X) G if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
1 a. q5 i: x1 L: T "road. Either increase the amount of roads "; h) ]! a. O6 R
"by increasing the GRID-SIZE-X or ". g [ z1 e- Q/ c: |; y6 [5 K
"GRID-SIZE-Y sliders, or decrease the "
5 f+ ~/ i9 H* Z "number of cars by lowering the NUMBER slider.\n"
9 U& ~+ Q, P5 X "The setup has stopped.")$ O. s1 V/ x. a
stop" Q$ X) I) l- q) q6 Z4 `& n
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1 n B0 a0 O7 s+ {( s ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
# H) g3 v2 C4 t+ ]5 k0 q crt num-cars4 n/ t% |. b5 _% [4 N, y( R( U( @
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- u0 W% f( `& I setup-cars
4 v3 v9 |; ^: z% ?5 _ set-car-color
" ?- h% c0 z) b9 X' C# s" a record-data2 ^* n4 h# g, v3 N1 d: Z
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;; give the turtles an initial speed. b% ]* ^) g: @) y
ask turtles [ set-car-speed ]2 @6 Z0 T, ~( k5 c# R
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reset-ticks6 z! ]( ^4 j: c: ]5 ~( L
end
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) j/ h) }. N+ }8 @* c8 y- z;; Initialize the global variables to appropriate values
# w8 }; T- @8 S( s( L j: ito setup-globals
! B- y( L! |3 W% c# f! ^9 i, [ B# b set current-light nobody ;; just for now, since there are no lights yet
7 _% b+ l3 A3 P: ~" z. a set phase 09 H, Z2 \" } z) b* I
set num-cars-stopped 0& |" o# E8 b# |% i1 V$ k
set grid-x-inc world-width / grid-size-x
# D3 o8 n1 b6 [% h set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# |1 ]5 h1 |* j m3 c% b set acceleration 0.099
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" i0 B$ i8 E1 x;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
+ D* E9 G7 f2 U0 s( F/ E, I' M;; and initialize the traffic lights to one setting; s: o' a- K5 W1 V O& J+ G
to setup-patches
. y5 f$ h. M+ [5 G ;; initialize the patch-owned variables and color the patches to a base-color/ M1 O4 H' z4 P6 J* i2 ?( x
ask patches
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+ {" C& t/ X; e8 P3 s set intersection? false
; _# Z' |8 e# G5 T set auto? false
/ Y8 i4 {: {5 a8 d1 H% H, Q) i set green-light-up? true
7 s4 Z+ M% ]( s- H& @( W4 P1 s set my-row -15 {3 T' _& a3 U& A) k( P& h2 w
set my-column -1
5 h7 y0 L+ X* E" ?0 v, Z set my-phase -1
2 C% ^& V* Q: @& }: g" @) f6 C' Y K set pcolor brown + 3
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) T# F6 x" v6 B. q$ U* V$ ]- V ;; initialize the global variables that hold patch agentsets! A: R! u) d' G) _3 o
set roads patches with
: C# x$ R; U' {" ~5 v [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" S% I2 c. Y) I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 |& r; e) V8 R% c3 p* B& G# v6 w
set intersections roads with8 V% x" P2 h1 Q Z. \5 D8 L9 G
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
/ Z+ D. q: R+ W5 ]: ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)], ]( r0 c1 q( b! x
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ask roads [ set pcolor white ]7 p, w6 _9 P4 m
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
: K6 }% g6 e; X set roads patches with) q( ?/ Z0 W4 Q: y) p7 c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ |7 F( |8 o) v8 B: c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 D' n2 j; R- j+ A$ ?6 F
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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