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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。3 B% i! l& \6 G i. w- \* b
netlogo自带的social science--traffic grid这一例子当中,
! [" l! L1 a+ [! W! S1 Nglobals7 H. ~* \1 D' \+ B0 I6 {7 |) M
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grid-x-inc ;; the amount of patches in between two roads in the x direction
6 ^5 f9 k) ]0 a( H grid-y-inc ;; the amount of patches in between two roads in the y direction1 s! | x& [. M2 H; w7 m
acceleration ;; the constant that controls how much a car speeds up or slows down by if, A, F& E, B% n7 J" x$ P
;; it is to accelerate or decelerate
! F+ Z. d# L R6 A2 h phase ;; keeps track of the phase
5 F3 q5 j, V w/ |: |9 ^ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure) A2 X! Y8 _" B( L% h2 k3 _
current-light ;; the currently selected light. f! V1 x! W6 E& i: o! G
# b" c/ i( M/ A$ X ;; patch agentsets/ Q$ }- i0 c8 C& A! U
intersections ;; agentset containing the patches that are intersections/ k F; ?! ~5 C- |; y+ P
roads ;; agentset containing the patches that are roads4 W% |" `8 F. L5 r( N
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turtles-own- h2 ]/ m+ ^) a- R5 i
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speed ;; the speed of the turtle
8 k' h0 m0 U% h up-car? ;; true if the turtle moves downwards and false if it moves to the right, A8 A5 O# m# y, G- x1 J
wait-time ;; the amount of time since the last time a turtle has moved# \; H6 `8 ]% S: Y$ s8 R7 K( X
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# Y: U& F, P# s) `" ypatches-own
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intersection? ;; true if the patch is at the intersection of two roads
! p. S- \" h& E! f* E& Q green-light-up? ;; true if the green light is above the intersection. otherwise, false.
" l& `7 @3 ` _3 ?7 \8 R: I/ ] ;; false for a non-intersection patches.! `! ]0 w; H8 U# I$ j+ o" s9 x
my-row ;; the row of the intersection counting from the upper left corner of the
* f& P! k) ]# K1 `! v0 E ;; world. -1 for non-intersection patches./ N& f7 ~" ]# R/ t! r6 B$ `, M
my-column ;; the column of the intersection counting from the upper left corner of the& g1 L& L0 @3 f+ N4 N
;; world. -1 for non-intersection patches.- w. X# D1 P% T$ U, i" W
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
7 A8 ?! U. ?6 [. | auto? ;; whether or not this intersection will switch automatically./ f3 {) t# Y9 Z
;; false for non-intersection patches." y. e' P b% n- j
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;;;;;;;;;;;;;;;;;;;;;;' z. t: I( s+ {' ? O* {! i
;; Setup Procedures ;;
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8 q0 i0 l c5 e' w4 K;; Initialize the display by giving the global and patch variables initial values.: N1 D; w( j* l+ Z- N: @
;; Create num-cars of turtles if there are enough road patches for one turtle to! Y& G3 \& ]- x- ^& B8 k+ ~8 _6 e. v
;; be created per road patch. Set up the plots.
5 L9 A8 E6 U( ]to setup
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5 y' i/ J' b/ E3 p4 O setup-globals
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# R1 K! y9 X: L6 s" N* k" t" Y ;; First we ask the patches to draw themselves and set up a few variables1 z" R3 b( m5 M
setup-patches
9 t, y: d- r. h' G* W make-current one-of intersections
0 C( f, r3 T- x7 E; J label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)
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9 u( l6 X+ B, _* w8 q: f user-message (word "There are too many cars for the amount of "
1 p2 M0 l0 |+ u8 D$ J, B "road. Either increase the amount of roads "5 |$ @. d3 l0 e9 L, l3 @0 J
"by increasing the GRID-SIZE-X or "9 }/ L2 j7 c/ V' m$ _* x
"GRID-SIZE-Y sliders, or decrease the "
2 h. e0 y6 T6 N* F "number of cars by lowering the NUMBER slider.\n"# }, [/ O, B4 o1 J! @3 q# |
"The setup has stopped.")
: ^7 G) E! a" {' v7 w; K# B3 R5 h stop( X. B0 }; R3 A0 A! s
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8 f( i2 Z2 G R) Y ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, y& I) v7 Q/ ]- j& U9 s" }5 N# i. w& A crt num-cars% ?$ p% {7 _9 }; r+ {0 H
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' Y3 J0 m; J* i% ~( i0 K setup-cars
+ q* l7 B! n% j" M9 o1 D set-car-color5 ^$ c% `- e. V
record-data
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;; give the turtles an initial speed
9 ^) K! {9 U( z. q) T- J: B6 M3 W ask turtles [ set-car-speed ]
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5 }; M# x1 D5 @' R, T ?5 N reset-ticks' s+ D0 w- k, K/ }! I2 K. f
end
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! r/ p. y2 f' Y6 X9 u Q;; Initialize the global variables to appropriate values
+ u3 p3 V& I1 J; Lto setup-globals
% j- q: O0 R8 E( ^4 ]9 B set current-light nobody ;; just for now, since there are no lights yet
+ E7 d e% y) K+ y3 k1 v set phase 0) ^7 o8 J x3 p' D. X
set num-cars-stopped 0
& K- }7 B1 \: q8 ^* O& U4 _5 [' Y set grid-x-inc world-width / grid-size-x6 [( }9 F7 G9 g3 C
set grid-y-inc world-height / grid-size-y, v, f( C& z; [; \; J" x2 g
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
. o+ {3 o* ]: w% [* g set acceleration 0.0993 M" X, a# F# V1 O1 x1 k
end2 I' I5 p* Z8 J/ q; u% Q9 B5 O; J' l
, z' v) ]4 P- x6 N;; Make the patches have appropriate colors, set up the roads and intersections agentsets,7 H5 o V$ ]2 s1 I+ Y- {" O- d
;; and initialize the traffic lights to one setting
: G7 t4 z% K) I9 |. W9 \3 V0 eto setup-patches
- @& { P) G6 O2 l2 S5 U0 ?$ t2 T ;; initialize the patch-owned variables and color the patches to a base-color& z6 G9 J$ t9 k7 Q9 h( a4 e( K
ask patches. r+ x: C A/ Y7 U
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set intersection? false
6 C2 u3 {6 \) i8 y set auto? false
5 w' ` c A q set green-light-up? true
: b$ G2 q& Y# T set my-row -1
1 d1 K' k- K; |! E7 P& @ set my-column -1% g3 Y3 D& Q: u7 A
set my-phase -1
+ ]8 A7 ]0 H) B! ?; @- V) T7 e set pcolor brown + 3+ ?) ?3 G" k$ f7 d
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) e, j, r1 h' t" M/ b) B ;; initialize the global variables that hold patch agentsets
+ @+ T5 ~+ {3 m3 i# P9 Z! A set roads patches with+ I( v3 M! e. z. ?2 s
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" }1 U- G- G0 _, _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- w+ X' |- p ?* }4 q, \% z: _ set intersections roads with. {4 F$ p, y0 f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and. [* W8 u I4 e( E8 M! l
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 N9 o* W6 M, }2 z: k
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ask roads [ set pcolor white ]9 g( v- A: V1 ?$ {: ?; A
setup-intersections
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" c% J8 h/ I1 a# R其中定义道路的句子,如下所示,是什么意思啊?6 S, O& G4 v ]! k: n- K
set roads patches with& ~9 a) G2 n5 s3 n% k4 `+ m$ A' K
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or# j3 y* T* f' U( ~. V) l! J, T
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 P2 y2 M X* a! P% Q$ s9 f9 O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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