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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。
$ I; a. C4 ]/ l8 ]netlogo自带的social science--traffic grid这一例子当中,
9 r* k% L( m) o& L7 K) G& L& pglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
' w" W2 p4 A2 C4 [1 D- E grid-y-inc ;; the amount of patches in between two roads in the y direction+ [5 M& g6 v3 l8 u- t6 v
acceleration ;; the constant that controls how much a car speeds up or slows down by if
. d% W' h2 E' G% i/ i" f ;; it is to accelerate or decelerate
8 N4 o+ D2 M/ ?( u+ z phase ;; keeps track of the phase. p! y& H1 ~% y; a+ h4 a
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
7 a, ~, L: S% |) i" s" i3 g4 B6 \ current-light ;; the currently selected light
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9 F2 `+ b' M4 _ ;; patch agentsets! w5 h: m) L& ]; ]/ l% h# F' j
intersections ;; agentset containing the patches that are intersections
7 y: K. w1 D4 x roads ;; agentset containing the patches that are roads
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5 s3 G! q Y1 @% [6 |turtles-own$ s: Y: ?' D, k- F4 p8 J* R
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speed ;; the speed of the turtle
0 W; `" G; u& w5 m$ F up-car? ;; true if the turtle moves downwards and false if it moves to the right h- V6 S" l/ E3 S( c$ P
wait-time ;; the amount of time since the last time a turtle has moved; T) C. s( y; @/ T
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
9 I6 F' _. P, H4 C green-light-up? ;; true if the green light is above the intersection. otherwise, false.; O7 ]) e. J4 ^7 ]9 z `
;; false for a non-intersection patches.0 b9 P4 R9 s. X+ P
my-row ;; the row of the intersection counting from the upper left corner of the6 M6 M3 P' G! R& ^4 m/ h
;; world. -1 for non-intersection patches.
9 W+ l9 k9 d! j# ~4 N my-column ;; the column of the intersection counting from the upper left corner of the
, A% ~! f+ @2 C4 ^6 M, d' F3 y, _ ;; world. -1 for non-intersection patches.
. Z" S' `6 u1 R1 }' R3 t6 g my-phase ;; the phase for the intersection. -1 for non-intersection patches.) X' G1 b8 s% ]1 _: k+ ]7 m% ~: b; B6 j* q
auto? ;; whether or not this intersection will switch automatically.
) B9 u N& ]$ E9 P- A/ i ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
! n3 X7 G0 d; R& ]( _;; Setup Procedures ;;9 A O2 j v* q( N- p$ k% |2 H
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
Y" i: m0 U0 x! C' t2 e5 z;; Create num-cars of turtles if there are enough road patches for one turtle to
( f& k, ?" X; u" U;; be created per road patch. Set up the plots.
+ ^ q# U( `) C+ s" zto setup2 W ^: Y' o3 x6 E! j
ca
, d7 F, o1 w. s3 V% Q setup-globals
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* g7 Z. m0 A9 |/ Q: c! Q- f1 p ;; First we ask the patches to draw themselves and set up a few variables5 K0 A7 S1 F) j6 l1 {' L6 m
setup-patches2 V8 m+ `# ]9 Q9 S3 O- U
make-current one-of intersections( W7 `0 S- e& b
label-current; \* b; C3 x+ w0 G/ o9 O! T$ p
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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 "
# x3 k5 c7 n$ G( l) J5 N$ F "road. Either increase the amount of roads "
% T3 S; f( X9 k1 J "by increasing the GRID-SIZE-X or "
6 x0 M$ I; Y) G- d "GRID-SIZE-Y sliders, or decrease the ") |+ {7 p. ]$ E# x- o2 i0 h( |: L
"number of cars by lowering the NUMBER slider.\n"
7 b8 E: h1 F" D) P8 j( e* h "The setup has stopped."); y6 {' d2 W" y2 P# }8 K; z
stop& P: x! C# z0 n/ L/ }$ Z
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color/ f+ B. R5 @3 s1 S
crt num-cars
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setup-cars
' N. m/ w6 n5 Q- [; K) ?) j7 [0 J set-car-color
+ W b, U8 I2 Y$ O2 a% `0 p4 J# E* f, l record-data, b( \! v& z- t& S r6 u
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- f, i1 o5 k$ ~) [" Z5 Z. E ;; give the turtles an initial speed( L8 K5 {/ M( H" c( c
ask turtles [ set-car-speed ]' J' s7 r( y7 W4 ^( n" O
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reset-ticks
0 s: V" q: _# S& |end
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3 u0 n8 l5 H; `9 s0 t- m;; Initialize the global variables to appropriate values
. Q: d% J8 l4 R- v/ J, _, T& ato setup-globals
1 s/ s9 D* ?: d2 E set current-light nobody ;; just for now, since there are no lights yet8 J! I( o# S( V4 }% |* T# J5 L
set phase 0. _% A; U& J/ I
set num-cars-stopped 0
, G; g) T; U8 S set grid-x-inc world-width / grid-size-x2 D" J% h5 F& U7 y4 L2 ]& U
set grid-y-inc world-height / grid-size-y
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$ c6 Z+ @% [, C1 b, E( m" d ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary9 \! r5 }( P' q, u/ o
set acceleration 0.099
% B* l7 J. N9 | j9 a' r, F# ?end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,9 \. G- n* S* _& b- J
;; and initialize the traffic lights to one setting
/ P" h8 M; ?+ _/ `; ^2 oto setup-patches
% a4 f7 M# O) E' N5 U ;; initialize the patch-owned variables and color the patches to a base-color# N) t) _5 L. U0 z* b
ask patches+ s" h+ x1 `, e
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set intersection? false2 a: _6 t4 G2 n( z- u* q# {: ]
set auto? false
$ R5 D+ l6 ?" ]9 @8 D6 X set green-light-up? true
2 H1 N3 u/ [" _/ O set my-row -1
* O3 E) |1 [& [! P set my-column -16 s0 V$ x1 O; s
set my-phase -1% W+ h6 y { T. S2 `7 `
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets, p( `2 _ G9 [1 v5 W; d; y1 n
set roads patches with/ b, e2 ?" c" q2 q3 q' f5 r: z; S
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ ` P) R6 B5 W* D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, b( J3 e% k3 m( g set intersections roads with# a1 M3 ]" ~! K' ^# o
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
) C$ u0 C# q0 ?" W$ K (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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* x9 S" [: p% d9 H ask roads [ set pcolor white ]
0 u; n+ R# B' }6 ] `5 `% s setup-intersections$ ~+ {" P. X( S& S# Z* P
end
) H2 Z1 g: N3 k3 U其中定义道路的句子,如下所示,是什么意思啊?2 G5 i1 A. E' o9 }+ Z
set roads patches with
- X+ m; s7 o5 T' k% x( X3 J [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 y$ E+ u+ h) Y# ? (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 r$ o* U/ N0 M! N; h4 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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