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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。
$ _# l7 d# T) P3 s7 Rnetlogo自带的social science--traffic grid这一例子当中,
0 A9 A' S& G. A: A* i/ Kglobals
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9 o7 F; z( L2 Y: J @ grid-x-inc ;; the amount of patches in between two roads in the x direction
m. ]* o7 f0 E7 Q. |9 s grid-y-inc ;; the amount of patches in between two roads in the y direction% |" G$ f" `7 C p; c
acceleration ;; the constant that controls how much a car speeds up or slows down by if
- i( x0 p# K: u( ]7 |3 k. } ;; it is to accelerate or decelerate
" o! s5 A C' o# K4 V+ | phase ;; keeps track of the phase
) R5 }) h; B: E8 F% F) ^ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure% K' ?* t: ^$ ^4 e
current-light ;; the currently selected light
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;; patch agentsets h! J/ j+ f2 J, r/ n# ~* x$ d
intersections ;; agentset containing the patches that are intersections
; e S+ r8 X; C4 V roads ;; agentset containing the patches that are roads& m7 g# A6 `' e4 N
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turtles-own
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speed ;; the speed of the turtle B- B9 x. M& T/ ?1 ]
up-car? ;; true if the turtle moves downwards and false if it moves to the right$ @" _3 o+ o" C1 O
wait-time ;; the amount of time since the last time a turtle has moved
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9 k8 A0 n* X" e% o" r# t$ Upatches-own
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intersection? ;; true if the patch is at the intersection of two roads
% r6 I/ r9 ]1 ^) F @5 P green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 R Y. e+ S# y$ l% \
;; false for a non-intersection patches.6 B; l, C# I; P+ j5 a8 E
my-row ;; the row of the intersection counting from the upper left corner of the! W! R2 _5 z$ d9 k0 T5 j
;; world. -1 for non-intersection patches.
! B% S$ ~ i4 y9 W1 g my-column ;; the column of the intersection counting from the upper left corner of the" N# V% q0 X- T& ^8 o
;; world. -1 for non-intersection patches.
) m2 O4 E6 N8 R" n' n6 T/ k my-phase ;; the phase for the intersection. -1 for non-intersection patches.
2 q2 s( {# C3 i6 Q auto? ;; whether or not this intersection will switch automatically.* D2 {& p' Z2 V+ k, \
;; false for non-intersection patches.
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( l" j9 ?" u1 b2 m;;;;;;;;;;;;;;;;;;;;;;3 b& a% M4 R/ W* r
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.2 d4 C* m) h3 P2 F/ {* o7 i# [
;; Create num-cars of turtles if there are enough road patches for one turtle to! S6 M5 }8 E: c: c
;; be created per road patch. Set up the plots.1 E9 Q) F& {/ F
to setup# h0 [8 F' ^3 G2 l) e5 E
ca
$ i, c; k9 @% i1 W0 ]! r, a& H Y6 { setup-globals
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7 C7 j# G9 `0 S# R- _ ;; First we ask the patches to draw themselves and set up a few variables
2 ]6 l4 p) U, `( P( c setup-patches
7 E* g1 ?" e) ]5 Z make-current one-of intersections& S$ t9 L s/ @. M
label-current! C9 x/ _1 P# V1 }- w
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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 "* C# z' x; P9 W6 q% G
"road. Either increase the amount of roads "
: k4 r1 R2 u0 D; ?1 ?* n. o# c; O "by increasing the GRID-SIZE-X or "
^: ^( W& D% z; |+ U "GRID-SIZE-Y sliders, or decrease the "5 W* k' F* B* F6 q0 r3 r: u
"number of cars by lowering the NUMBER slider.\n"8 i# F' Q& g# [, w9 b) n1 A
"The setup has stopped.")% Q8 H2 u9 u1 a+ m
stop W6 F" ~( G' k# q
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color m0 w* `3 X. B0 v' D$ a
crt num-cars j) k' b3 R$ \$ e- e9 ~7 T
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setup-cars" T% i0 \/ q# v+ [. x: h) E
set-car-color& ^) o2 w5 {) U' U2 @; S
record-data
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Y! Z+ u( U! U! h$ p1 @" c ;; give the turtles an initial speed
: \! E% _; Q7 L H. K' i2 F/ W ask turtles [ set-car-speed ]
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reset-ticks: v- k0 \* K, Y( s3 X( G$ [9 W4 f
end" w6 M4 I4 O* ~1 a7 m6 s5 n9 U
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;; Initialize the global variables to appropriate values; U7 W7 C4 o) }
to setup-globals# h) @7 i: t. e3 Q+ {9 d& N6 _
set current-light nobody ;; just for now, since there are no lights yet
% l6 [$ J- g4 V4 s3 Q8 s( U set phase 08 N, R, |& L0 r4 d
set num-cars-stopped 0
2 `/ d ]$ t2 b set grid-x-inc world-width / grid-size-x8 e: Y0 D* a, E8 z) q$ E7 V7 l
set grid-y-inc world-height / grid-size-y* E, ^" j' D9 d7 B2 G4 A. Z
2 T5 F, _8 W( Y+ n9 ^7 p ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary5 x# T) s* [. Y: M( R4 L
set acceleration 0.099( L- P K" [- s5 j0 i" ^. B1 p
end1 F, J* q6 r0 Z. o2 k; ~3 n
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& S, b, e0 H# Y;; and initialize the traffic lights to one setting
}7 B2 U N* g9 k; n0 Q9 ~: R" Kto setup-patches# a* r: M' G( n# P7 h" _! ^
;; initialize the patch-owned variables and color the patches to a base-color
0 l9 Z- V# H. v6 j4 n+ I! M ask patches
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7 {1 n# q/ ]1 ^5 { set intersection? false0 N' B4 c3 ^' @
set auto? false3 `7 |6 o* q$ s& T
set green-light-up? true
( l$ {2 t. R, N7 n2 W, B$ z set my-row -1* C6 R2 Z2 ]! W
set my-column -15 t. j- ~9 p) q8 Z
set my-phase -14 y j6 K" b0 A7 U
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
( `8 V$ ]# J: Z5 Q' d3 X7 s8 a set roads patches with1 {& D) d9 U/ P4 C% H0 S
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, r9 n a Q7 X& V% V& Q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, i& y5 m* c7 J; F( c set intersections roads with
" \& U' j% V: Y7 n- Y. Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 t* G; _: X9 _" {5 ^) v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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8 u9 l% F" c/ o' w# k ask roads [ set pcolor white ]+ a& a# y* O9 X; r7 I2 ^
setup-intersections
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6 y9 c8 B0 @/ a( `& y其中定义道路的句子,如下所示,是什么意思啊?
$ q/ [& B: s7 A set roads patches with6 T6 R# f, a. R' A7 T2 u2 f) g
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 I+ G G8 x9 L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ r/ ?5 U o3 D5 k$ n8 F a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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