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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。
8 B; y2 ?3 z* q9 y R6 R8 ~netlogo自带的social science--traffic grid这一例子当中,1 C a, c6 `0 r Y$ m- w
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction Z0 K* q# \# M! |* U- f( Q3 {
grid-y-inc ;; the amount of patches in between two roads in the y direction r2 F+ |. n( F# u* s( Q* T
acceleration ;; the constant that controls how much a car speeds up or slows down by if
' o' w. \, n: D4 y- i& [ ;; it is to accelerate or decelerate( V% M1 Z; y! }' p& \) W: `
phase ;; keeps track of the phase8 ?8 v: {1 @6 a5 e. L" |* c: E
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ t" c4 O! A6 G7 a/ n
current-light ;; the currently selected light6 T; _1 g1 w5 @2 S4 f4 @9 ~
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;; patch agentsets2 I, E" H# k' U' ~7 l1 R' m
intersections ;; agentset containing the patches that are intersections
7 N% F, j# o) v: t1 y roads ;; agentset containing the patches that are roads& z% e$ D9 E' ^7 k
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- T! f. K2 A; Jturtles-own, G9 H* s* s8 H& q6 X' t
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" `' @5 Q# h2 [- ]- \ speed ;; the speed of the turtle# `' R ~ ^$ N) N+ d3 _8 O
up-car? ;; true if the turtle moves downwards and false if it moves to the right
8 |% y% i( W& Y1 m6 F wait-time ;; the amount of time since the last time a turtle has moved6 D; F W. A7 U! }! D
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patches-own, m: V% z' z# S" L& p9 K
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2 }2 |4 l: b, J% N- T9 ^3 r intersection? ;; true if the patch is at the intersection of two roads
3 Y: c1 s: J& a) ^) f green-light-up? ;; true if the green light is above the intersection. otherwise, false.3 W( R& U- t" w2 u
;; false for a non-intersection patches.
1 w+ E8 f$ X% g ]% J+ O my-row ;; the row of the intersection counting from the upper left corner of the4 B! J4 v* H1 V# `* p
;; world. -1 for non-intersection patches.: d% v6 ^: G3 k' \) x1 Y( x. y
my-column ;; the column of the intersection counting from the upper left corner of the
, f, u! L- [. t7 _: L ;; world. -1 for non-intersection patches.
* i. Z R( }( n E1 `6 s* q my-phase ;; the phase for the intersection. -1 for non-intersection patches.0 R% j1 g$ `' p! s& v" S9 M
auto? ;; whether or not this intersection will switch automatically.8 }0 w( L2 {8 D' u" d C
;; false for non-intersection patches.
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& A+ d% P: C) o$ X- U;;;;;;;;;;;;;;;;;;;;;;! z: @( {9 z$ P9 o, R% k% r1 [
;; Setup Procedures ;;
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: E+ a. }9 `1 X. m;; Initialize the display by giving the global and patch variables initial values.
0 J @8 ]1 Q4 `2 S( d;; Create num-cars of turtles if there are enough road patches for one turtle to. O- J) B. I% _/ |. w& h$ l/ ?5 p6 _
;; be created per road patch. Set up the plots.8 T" K, R4 ^2 G% Q; M' c, r
to setup
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;; First we ask the patches to draw themselves and set up a few variables6 K4 m7 F1 s" b) D) d
setup-patches
h1 D0 C1 S; _( ?$ U T make-current one-of intersections1 t! g$ L" w5 p( X* Z% W
label-current) }5 r0 B& [8 e
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set-default-shape turtles "car"
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if (num-cars > count roads)" |, i8 t* y4 G/ g5 `$ D1 ?/ v
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user-message (word "There are too many cars for the amount of "
/ M6 n0 x5 \" b! U; K+ Z y0 g "road. Either increase the amount of roads "! V; t3 }" H1 ~( k0 s
"by increasing the GRID-SIZE-X or "
9 V: {9 z, e* C' G' z% X "GRID-SIZE-Y sliders, or decrease the "
/ @8 c, ]1 a. G& _6 ~7 X "number of cars by lowering the NUMBER slider.\n"# g8 v+ q5 D* b Q! \; R# ^
"The setup has stopped.")
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/ q# |1 s0 L; k$ w% y* k" D ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, d6 ?7 t b5 d& L crt num-cars4 P7 d( K4 e2 }0 e! L' H
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2 V) w: ~$ j. I, z9 E. M4 I* I setup-cars
' V$ W' m5 T' a set-car-color* j# V5 @7 _3 X+ C# P
record-data D5 U V( B3 ]. P) u7 b
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;; give the turtles an initial speed! }! Y* T& F5 |- F6 B+ Y, u
ask turtles [ set-car-speed ]1 ~! J* Y. X- {9 i/ n: s
0 _) S1 \) f. Y. e: _9 M. N reset-ticks T% b3 I$ c" F5 m
end/ j" \- F3 B$ k7 H
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;; Initialize the global variables to appropriate values+ y( v& l2 M8 ^+ Q, |& x/ W
to setup-globals
/ a- w, g7 ]+ K x set current-light nobody ;; just for now, since there are no lights yet
! K t# ^& Y! D2 j set phase 0
4 @: U- u4 a& H5 h9 D set num-cars-stopped 0
( R8 a; Z3 p5 a/ Z( U3 h5 z$ Q set grid-x-inc world-width / grid-size-x
5 n3 u' {# i1 m" N9 o set grid-y-inc world-height / grid-size-y
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- ?) j+ P# G( a9 |/ L; l3 L& T$ b ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary+ Y. y3 o* S6 ^" p
set acceleration 0.099
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! h! K0 j0 I$ C8 V, L;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' p5 T5 y- V4 `% ]: f;; and initialize the traffic lights to one setting% ]2 V* }7 [0 j/ E1 p P
to setup-patches. |$ N% F, P; f K) ?) s6 |' F
;; initialize the patch-owned variables and color the patches to a base-color1 |( c9 Q# _, x A1 K
ask patches; C+ i7 J- B2 x* V- _- `
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! m1 `1 U* ^+ N set intersection? false& W1 \! ^: O0 k3 X7 @* a
set auto? false2 z, P0 S8 y; F4 N2 S
set green-light-up? true, h+ M( ]# G( Y" h. B% |
set my-row -1) p: a( M- n& O2 K
set my-column -1
/ o! A$ D9 ]% e7 Q set my-phase -12 O; i0 I I8 d' Y2 I" m7 V. l
set pcolor brown + 32 B3 ^' p/ @4 [6 ]8 O
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! n/ v% ?8 J8 [- y( Y; O2 B ;; initialize the global variables that hold patch agentsets
- K$ G4 R4 N8 g* n1 a set roads patches with
& j( R- A0 Y6 k8 H' N# \ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 W7 R. r9 \4 m6 E
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 H% t9 M4 V& u3 f set intersections roads with
% A7 j0 x9 X n6 A& v+ E2 G [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ a M0 {- w& L( e0 X (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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; |8 A2 _( K- h+ T. } ask roads [ set pcolor white ]
4 ^, B n; w/ I0 {/ k% |4 u# w setup-intersections
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* t( j: M" v4 O) ~其中定义道路的句子,如下所示,是什么意思啊?
' V0 P9 R/ J8 I* j; p { set roads patches with6 U) L1 t% i0 Q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 J8 J) Q4 x% a( o! @3 a; m (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- j0 H% y* j3 o& _4 f0 @* x, I0 l) I
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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