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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。
; y, `' h$ e; Q* e3 ~netlogo自带的social science--traffic grid这一例子当中,; o4 _, j7 g% N/ o+ k; u' }2 i' N! x# |
globals
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( B" D; O6 Q( \' `+ ]" @( ~ grid-x-inc ;; the amount of patches in between two roads in the x direction( a4 S1 c* \6 b, d
grid-y-inc ;; the amount of patches in between two roads in the y direction
% L b; }6 m6 Q acceleration ;; the constant that controls how much a car speeds up or slows down by if+ Y, T# X, b% B a
;; it is to accelerate or decelerate3 |7 @8 g( j" N; e( ?$ \2 S) q7 h
phase ;; keeps track of the phase
' i4 _% k; i9 Y num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
E' G# A1 J5 {/ B current-light ;; the currently selected light
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;; patch agentsets
) ]2 d* n6 s% @) ? intersections ;; agentset containing the patches that are intersections! ~( M6 P2 Q. i6 C9 w+ ~
roads ;; agentset containing the patches that are roads% h$ V' P2 H. q) r u& \; J* E
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+ S. V9 P* }4 _ ^. X- E! ~turtles-own
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speed ;; the speed of the turtle! y/ r* J6 f! P; u, l6 L# \
up-car? ;; true if the turtle moves downwards and false if it moves to the right3 l( z2 T/ j* X. F0 p, s3 @
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
6 y8 W D7 J9 x9 x4 g$ I green-light-up? ;; true if the green light is above the intersection. otherwise, false.
+ [) `) M& Z# J q( ` ;; false for a non-intersection patches.
) m" T- P2 Y+ D1 t* J, A+ ~ my-row ;; the row of the intersection counting from the upper left corner of the
. g1 S2 y, {. `) z: B! M ;; world. -1 for non-intersection patches.) B8 d6 F6 l0 k' R1 l
my-column ;; the column of the intersection counting from the upper left corner of the6 v" }* {0 t8 B t& B& j
;; world. -1 for non-intersection patches.* h9 ~5 G0 y! \1 R8 X3 l& W
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
- q# i7 U8 r8 {. o5 G6 z T1 H5 ^ auto? ;; whether or not this intersection will switch automatically.$ j) M( K; e1 V
;; false for non-intersection patches.9 _% N7 m% o% G0 H; c) X
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+ E2 h2 R% w+ r; ~+ m;;;;;;;;;;;;;;;;;;;;;;! @% n: Z; [% b0 ^2 k$ }
;; Setup Procedures ;;! V" [ U$ n# }( \4 {
;;;;;;;;;;;;;;;;;;;;;;3 k" b7 ^! P3 w4 k# q' t
' X. c3 e; C+ K6 j* o;; Initialize the display by giving the global and patch variables initial values.
* H# w7 ] t5 _, @" @4 ?;; Create num-cars of turtles if there are enough road patches for one turtle to' P- R6 R# F t; h
;; be created per road patch. Set up the plots.5 W9 Z# }3 l; q( P$ {) D4 z
to setup
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9 n2 B. F* r/ g( @ setup-globals# O+ ]8 Y. S) r& l
# j( d8 l# v8 X- i! a ;; First we ask the patches to draw themselves and set up a few variables% P* g- V/ t- s8 T
setup-patches- H; w) `# C$ F1 ?8 Y
make-current one-of intersections+ a) W) Y! U7 d( s4 Z# W# ^9 `
label-current* |& [; ?3 n' ]+ Y% _2 |$ V
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set-default-shape turtles "car"
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if (num-cars > count roads)
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. |/ t8 Q- d( X user-message (word "There are too many cars for the amount of "6 M! K1 D% S- n- M5 m
"road. Either increase the amount of roads " s0 Y) m B' C/ j0 Y
"by increasing the GRID-SIZE-X or "
' e5 C4 O, V% ^9 D4 u "GRID-SIZE-Y sliders, or decrease the ": z# V+ ]/ S" X* q; ^1 p) j# O
"number of cars by lowering the NUMBER slider.\n"
, h( e' S9 z3 B4 F1 m, z! s. T0 H "The setup has stopped.")# j; a& e1 W4 N! c3 R/ r8 m
stop) D# H8 ~! E6 |7 u: S
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color* [; w' x( M3 P4 ^; Z
crt num-cars) ]# Y; F: c# {4 [+ T5 ]
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setup-cars1 d2 P7 I$ i& ^3 B1 n
set-car-color# o1 T& j- E9 g* i! s
record-data3 O7 n8 z1 N/ |* z* h
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;; give the turtles an initial speed
* P- Y8 r( T0 C; d/ @/ J" @+ i ask turtles [ set-car-speed ]9 T( ]. j+ ~5 j( ~
" W4 |; y9 s& y reset-ticks
* {$ Z* u( A k+ B( Z9 V( m; gend
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;; Initialize the global variables to appropriate values
8 \3 S" j# J2 h" V2 mto setup-globals
F( ?& F" C& A2 t% t: X4 M set current-light nobody ;; just for now, since there are no lights yet7 C+ Y n2 @6 I
set phase 0! t e9 Y0 g5 _, d1 T' X
set num-cars-stopped 04 v5 [' y Y) ]5 b
set grid-x-inc world-width / grid-size-x
' N+ @8 I. U1 J3 U( o4 j set grid-y-inc world-height / grid-size-y" ~( n. {% M- ]) O, ]
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
5 d, |$ F1 U4 d8 W' b# i4 y set acceleration 0.099
' L( i! w" T# b; \5 |end O) X) j/ H& d
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,( Y t- c6 R/ u
;; and initialize the traffic lights to one setting
, V, ]$ h4 J" j2 X1 n2 |5 l0 Tto setup-patches' q0 D: {3 |; r$ ~
;; initialize the patch-owned variables and color the patches to a base-color
5 y l4 z7 E8 {& X ask patches
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set intersection? false/ U4 `& M) j% p- I" j& }/ Y& F! n
set auto? false8 ~; l! _* k# h
set green-light-up? true5 W% l5 P& U7 M# H, N. h
set my-row -1
9 P1 X" e# {. T$ C3 z9 H1 w, k set my-column -1
5 R! \5 R0 @+ |3 M0 q set my-phase -1
! M7 \# A5 A$ v set pcolor brown + 3
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2 c4 g, U/ e2 i: `( n9 ~5 a ;; initialize the global variables that hold patch agentsets
0 K n* A( T/ {1 ^1 ^- t. ` set roads patches with
2 x4 M9 C7 ^% W/ I$ C4 v, ^ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" Z' [" [6 L2 T0 t+ n7 O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 e+ V0 F2 N/ b
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]* ]7 g( k7 _% {6 L8 x: f+ ]
! p$ ~4 e0 f7 c) B* C" v O ask roads [ set pcolor white ]9 z0 M' f7 j- C2 A& j0 g
setup-intersections. A- R& }2 Y, j8 T
end
% d, E! t6 {8 Z- `4 e: u. B其中定义道路的句子,如下所示,是什么意思啊?
& s: F4 l V7 b1 M* U/ g set roads patches with
# m) w; N6 t8 v [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
; S+ T- m: @5 Y5 W9 s( ?) F0 X (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# |" M" D7 c4 | S7 G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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