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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。4 D; K9 [4 K5 L) [' f
netlogo自带的social science--traffic grid这一例子当中,
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5 N# r, M, ^$ K; [1 ~% n% q8 c grid-x-inc ;; the amount of patches in between two roads in the x direction
+ ^) Y8 }; I _! ^! Z grid-y-inc ;; the amount of patches in between two roads in the y direction
. ^9 Q3 c% ^0 p# a& ~' | acceleration ;; the constant that controls how much a car speeds up or slows down by if
' r$ i7 t9 }& f2 i" Z$ n { ;; it is to accelerate or decelerate: n& @' I$ w( Q& {( n
phase ;; keeps track of the phase4 m3 Y' n- r$ p+ c& M
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure1 R) b# |1 z4 T7 o! ^
current-light ;; the currently selected light7 ^5 |& z' u5 Z! R8 z9 o" `# v4 `
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;; patch agentsets5 i' r, ?7 ^- C. h8 I) U9 e
intersections ;; agentset containing the patches that are intersections) C0 M! D' m, _% ~
roads ;; agentset containing the patches that are roads9 H5 I& R. h; y h
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turtles-own1 t+ ]8 u; K s9 @) C
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. ?6 n& A. Z5 g! F" S+ M speed ;; the speed of the turtle
& O! n8 _$ a$ |3 D. d up-car? ;; true if the turtle moves downwards and false if it moves to the right& ^! z, Z) {' M5 h/ y* h- B
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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! n8 ~* K8 V- O+ a+ e$ }% y3 w intersection? ;; true if the patch is at the intersection of two roads
9 Y& A9 C/ ?- ~- x: \( S3 S% y green-light-up? ;; true if the green light is above the intersection. otherwise, false., z U3 t: u8 b: X7 Z' J1 F7 ]
;; false for a non-intersection patches.3 n7 q, v. f( P+ ~( [/ G0 p* X
my-row ;; the row of the intersection counting from the upper left corner of the; e) m8 h( c+ u5 O3 K9 @3 O& u
;; world. -1 for non-intersection patches.
$ S7 O: J7 g9 |. c" J2 L8 L9 j' G my-column ;; the column of the intersection counting from the upper left corner of the' Z7 _5 x; M- N( z% x; K1 P6 v& m
;; world. -1 for non-intersection patches.0 `; M" D( j: c6 e" D; a/ X
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
6 W+ H. V; I) |: K+ T8 v auto? ;; whether or not this intersection will switch automatically. _1 A" J& a7 x) L% u
;; false for non-intersection patches.1 |! @8 O% I' X5 L9 N
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;;;;;;;;;;;;;;;;;;;;;;5 c" o" @, h8 K( d' f1 W
;; Setup Procedures ;;+ x5 \8 Y; P# p! ]6 h
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
; Y# O- S4 ?: I! I4 h6 S# E0 ~" c;; Create num-cars of turtles if there are enough road patches for one turtle to$ h" ~+ _6 x3 [9 H
;; be created per road patch. Set up the plots.
4 m5 z" U, G% k! J4 Sto setup7 h' C: e( S$ s* h8 j
ca
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;; First we ask the patches to draw themselves and set up a few variables7 z% F. [* J3 @/ w
setup-patches
0 i/ @2 p1 ~9 v+ b# Q, {- b# a- K$ g. b make-current one-of intersections
3 J. r5 g- H+ C label-current
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set-default-shape turtles "car"$ c7 L: X% C3 E6 x$ F
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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 "3 u' H$ M+ c* Z! j
"road. Either increase the amount of roads "4 C$ ~% @, h0 z8 ?& h: y
"by increasing the GRID-SIZE-X or "& F. p0 l: T5 ?
"GRID-SIZE-Y sliders, or decrease the "1 ]. w! Y7 G `, ]% c1 S
"number of cars by lowering the NUMBER slider.\n"
9 }4 j+ R4 j3 p5 a5 q4 y" [8 _ "The setup has stopped.")
8 e2 }, Q- D+ d8 J stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color$ r, D* _, G2 k# z9 X' w6 Z% F
crt num-cars
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" b6 N: B, t; P0 j! |( Z setup-cars5 x2 _9 X+ l: o& Y. R% U
set-car-color
+ t! q$ ~4 H0 `1 s+ u/ l' E record-data
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;; give the turtles an initial speed
# B& g: \2 p4 j6 \+ I ask turtles [ set-car-speed ]% x0 d1 I& }. @3 }: I. Y! F- {
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reset-ticks" M% v0 n4 B' g# n: E
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& H2 z* r, x1 r. F, O;; Initialize the global variables to appropriate values/ T: I4 J" @7 p g
to setup-globals
' M8 H7 V7 p9 f5 o/ a set current-light nobody ;; just for now, since there are no lights yet
" z( Q. ~0 Y; @$ h9 e3 a set phase 0+ q& }& q* `" E
set num-cars-stopped 0( l8 R. N4 o' h( e
set grid-x-inc world-width / grid-size-x
+ S# U$ b4 X2 }* y5 r0 ~& ] set grid-y-inc world-height / grid-size-y
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/ H* P4 u6 [8 s H ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: l, D6 g7 X6 Z+ o1 s% a: t
set acceleration 0.0996 J5 L1 q% C4 f% Y+ Q
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,( E' c* j7 o( S
;; and initialize the traffic lights to one setting
3 q5 _2 G$ i! E; q" |/ M W$ D( Dto setup-patches
; A5 [$ s# a- X; Q+ B1 H ;; initialize the patch-owned variables and color the patches to a base-color( P, |+ F) M! K& j' N- R/ o+ x! s
ask patches) T2 Y9 q2 V0 U5 T
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! i% L! E: [. m- X set intersection? false
2 q! b z. b5 H1 \" D/ ~( C set auto? false6 B3 G2 l! |4 ~$ {8 f
set green-light-up? true0 b" h4 D% ?7 \: ^# @# c
set my-row -1
' F; ~$ B6 U" p% z set my-column -1. D7 Q e6 ~+ C: b d' j
set my-phase -1" m" j; {, P* i9 b
set pcolor brown + 3/ E, ^4 u" F! d$ t
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( u9 A; _7 ]# d ;; initialize the global variables that hold patch agentsets0 H0 W/ Z5 B+ {" j _9 I2 ^: D- {7 }
set roads patches with
8 t- l/ W: R1 G+ H* i* N1 S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ Q) y& w/ v+ A
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: B- L- d9 l L7 k' }+ ? set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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% a& ?2 A2 x7 a; Y其中定义道路的句子,如下所示,是什么意思啊?" U" ?- @& S& a, Q" b! W* j4 \
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. Z9 \" }7 |' s
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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