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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。( i6 j9 U% _6 Y" m+ S
netlogo自带的social science--traffic grid这一例子当中,
1 B# i6 {# K4 O$ b$ X. f5 p1 U! tglobals3 O' x: w: V8 O7 s$ B. x0 {: D) i- y
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grid-x-inc ;; the amount of patches in between two roads in the x direction
( R+ E6 ^( J1 n2 S" P( [. G grid-y-inc ;; the amount of patches in between two roads in the y direction
- p' m, D" S9 n$ d( M. W/ i acceleration ;; the constant that controls how much a car speeds up or slows down by if
! ]: A4 O4 b$ I* }" I ;; it is to accelerate or decelerate8 Y; Q) U; r. Q7 F) U p
phase ;; keeps track of the phase
1 `" ~6 y) }8 O7 I num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure( G' [1 w; P, T! M( h/ o, `" R
current-light ;; the currently selected light
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;; patch agentsets0 ^& f8 J6 l \& c3 ~- Q: C
intersections ;; agentset containing the patches that are intersections
3 ]8 P( D" U% B$ P1 T$ @ roads ;; agentset containing the patches that are roads2 w+ c0 v/ q4 c
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turtles-own
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, F X* w4 o5 D/ g: z2 Y4 P9 b speed ;; the speed of the turtle
( `! b, y/ T5 f( I- W up-car? ;; true if the turtle moves downwards and false if it moves to the right @# \# D% O. x1 L. Q1 a" M! J
wait-time ;; the amount of time since the last time a turtle has moved* S/ @. J' B& J5 G, d* v
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patches-own( Z* p/ W1 ?/ n9 R% x* ]
[
7 f% \# |0 H& @ V r) g) V* k intersection? ;; true if the patch is at the intersection of two roads
9 L) V* D! m4 c- t- F3 Y5 I$ X. z green-light-up? ;; true if the green light is above the intersection. otherwise, false.# D5 x. P7 n8 d: u
;; false for a non-intersection patches.7 _/ _; _. e1 H2 B6 `, ?
my-row ;; the row of the intersection counting from the upper left corner of the( o7 m- f% B# y9 U& ^, d, Q
;; world. -1 for non-intersection patches.3 ]3 n) A$ E1 {0 i7 G
my-column ;; the column of the intersection counting from the upper left corner of the D. k5 ^( K6 l+ n
;; world. -1 for non-intersection patches.3 d% {6 { c4 c! |) x9 F" e
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 @- Y+ {* s7 g' K! _& I; A auto? ;; whether or not this intersection will switch automatically.
2 u7 F2 m4 x( i' u) Z ;; false for non-intersection patches.1 x; x: D; G9 x# ~
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1 \% d1 G j- h& g8 };;;;;;;;;;;;;;;;;;;;;;) l& v7 r9 p1 W* _" X2 N
;; Setup Procedures ;;( u/ p" D6 u+ ~% a. I3 ?" k
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;; Initialize the display by giving the global and patch variables initial values.! P! t, M4 i, Q$ R% D
;; Create num-cars of turtles if there are enough road patches for one turtle to
, `. L' |0 s6 r& V1 s0 @8 N3 x3 u( J;; be created per road patch. Set up the plots.
: d: J9 T6 s1 S$ {5 Y, Tto setup
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; d! a8 I( c t, z4 A; D setup-globals
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;; First we ask the patches to draw themselves and set up a few variables4 m) ~0 W! [* R) f
setup-patches
" W% t/ r* B- o2 q9 b. f make-current one-of intersections9 {1 m- h! v5 `( }
label-current
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set-default-shape turtles "car"
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- L& j. k$ F( N* T0 r, Y) i if (num-cars > count roads)7 B3 [$ _2 a# v9 O: K I
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user-message (word "There are too many cars for the amount of "; C' v# w+ R+ K, Z5 M \3 B4 V
"road. Either increase the amount of roads "
4 b3 r7 ?# J/ W5 ~2 K, | "by increasing the GRID-SIZE-X or "
2 k$ L+ x/ f; s- h) I! ^0 `$ e$ ~, {4 t "GRID-SIZE-Y sliders, or decrease the "2 r1 L( n# {4 Y& E3 C% @
"number of cars by lowering the NUMBER slider.\n"5 q+ B2 s3 z# Y5 n9 Z, G2 S- ^
"The setup has stopped.") t7 V( A, m. L3 M* s3 p: f
stop9 `$ X& N; L+ N4 K- v* m8 H1 w
]
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& [: U5 N! _; N; H6 L$ q$ G% T ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
5 d6 ~" o6 W! i. Z8 J crt num-cars; A; a# v9 }& D, R
[
$ }3 q4 w' ^8 H; T$ {0 r setup-cars' d5 g; o+ V, L; ^+ E
set-car-color9 I. Z1 [: \0 Q! p& R
record-data
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;; give the turtles an initial speed
7 ]1 H; q' c: Z" I( v3 ~ ask turtles [ set-car-speed ]7 s G& z1 ]$ m. n) G' `% s Z
7 S9 n9 P1 ]$ ~1 y4 c reset-ticks
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;; Initialize the global variables to appropriate values; j7 E0 J5 N. k+ h1 v, {
to setup-globals( T3 D% r0 k F9 V4 }* x8 e
set current-light nobody ;; just for now, since there are no lights yet
. @7 M8 Z+ S7 H* y set phase 0
. ^- s; k4 I0 N" G9 t9 ^) k set num-cars-stopped 02 |6 Q6 N1 }% i1 t& ~
set grid-x-inc world-width / grid-size-x. V5 e G: h. q& M+ P
set grid-y-inc world-height / grid-size-y
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% L& m E5 s3 v4 p" I* ?% O. z ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# e$ b# g, x/ G# }! ? set acceleration 0.0991 y. u4 c! }9 w/ ?8 @! N' i! T
end
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8 N2 Z6 \! E* H. H8 L. T;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) u, L( S+ y4 ~- m6 n6 D0 u# `. n
;; and initialize the traffic lights to one setting
" o0 I$ ^ q ]. Vto setup-patches
) {. F9 r2 W) C0 M$ j ;; initialize the patch-owned variables and color the patches to a base-color
. Q3 P4 z) g' Z7 u. [. { ask patches
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set intersection? false' m& ~; ?$ ^: k* L( q
set auto? false! k, `+ t- Y B
set green-light-up? true; O4 Z" \# v9 A/ u) `
set my-row -1
. Y {, l" D& r; v# w set my-column -1
}7 A% [2 q5 C; Q set my-phase -1! k5 k$ M+ g3 C6 [: `
set pcolor brown + 33 l M$ w2 ?2 p0 n4 R7 f
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;; initialize the global variables that hold patch agentsets
5 d$ }( R: {" p7 a" I% Y P) y! ? set roads patches with) P: c+ ^- D% _+ J" K; e
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 D' Y* U6 X2 {+ g9 q% O% A; z T (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% g; O Q% n$ N$ D& T& O2 J set intersections roads with
5 {1 |; R/ x# e3 }8 M [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
1 y' t" d! j! T } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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/ R& \" P0 m @. e5 L& f# ~/ ^3 y ask roads [ set pcolor white ]
9 ~; T0 K# ~% i; s$ m6 l ~ setup-intersections% H7 Q- w) z! X6 X* r# F h
end
+ C& N$ S/ n1 {2 t0 p其中定义道路的句子,如下所示,是什么意思啊?( A9 b/ U* Y2 |$ b& z$ C, o
set roads patches with, A# w# H9 v5 j$ p/ n
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ g2 o( E6 l1 N8 c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 l; a; M( u: Y' r. b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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