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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。
5 \* P: d( f& ^6 y! bnetlogo自带的social science--traffic grid这一例子当中,8 P5 H8 X- |: @8 T/ v3 p
globals2 Q/ q- @7 |- P$ u& T1 z1 m
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grid-x-inc ;; the amount of patches in between two roads in the x direction Z5 m# G% S2 Z" i
grid-y-inc ;; the amount of patches in between two roads in the y direction& d# ]- P3 Y5 Y' q7 R3 h
acceleration ;; the constant that controls how much a car speeds up or slows down by if" B0 X, A- p; `# }: q- H5 Q% N
;; it is to accelerate or decelerate. T9 X2 x7 k5 Y, H0 F% B
phase ;; keeps track of the phase
3 d& ?" i* z* |7 H( ? [& ?& k num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure5 S3 S# k' S K5 P4 W g
current-light ;; the currently selected light2 x1 s4 P7 N1 f# c8 L; x% o
! y, W! v" J2 I) {: o. W ;; patch agentsets
2 |/ g% u- u4 Q Z intersections ;; agentset containing the patches that are intersections( y2 k; L( H% W# \" \
roads ;; agentset containing the patches that are roads" d# i5 r4 T$ n+ ?# ?1 d% q8 T
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) r/ W2 V! ?7 N* _0 G) O( |turtles-own4 Q T: @5 H" v& [' b; K& ]
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" X; q2 B% a# u8 `5 d; H3 x speed ;; the speed of the turtle+ A* G+ b7 t3 g& Y( Z5 B! f
up-car? ;; true if the turtle moves downwards and false if it moves to the right
# [ @, G2 q2 r! K& K1 U3 [ wait-time ;; the amount of time since the last time a turtle has moved8 I- h$ E3 _, b8 D
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2 a" B+ e& @7 H1 b6 J+ bpatches-own
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intersection? ;; true if the patch is at the intersection of two roads
" G' B& i$ C6 d3 [ green-light-up? ;; true if the green light is above the intersection. otherwise, false.5 X! ~7 O. z- [* a" V
;; false for a non-intersection patches.2 a' H" _; b7 a) I9 R
my-row ;; the row of the intersection counting from the upper left corner of the
7 m( e6 D) M/ r8 |$ E ;; world. -1 for non-intersection patches.3 u2 t$ }3 e% K, h7 K
my-column ;; the column of the intersection counting from the upper left corner of the
/ |+ v/ u& c x0 D( B ;; world. -1 for non-intersection patches.3 m7 R% r: P: S' \3 C# N! \' X% w
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
p; d% d9 U; c9 f8 K0 A+ y5 G" n auto? ;; whether or not this intersection will switch automatically.
3 C8 E+ j7 k. u8 M3 k0 D: F ;; false for non-intersection patches.; ]; t/ c. T! V
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# c5 f D8 |$ c* c& m& f- H& V;;;;;;;;;;;;;;;;;;;;;;6 [& G" E$ J7 T. Z6 R* k' o+ r
;; Setup Procedures ;;
2 Z' z" h& W' I% r;;;;;;;;;;;;;;;;;;;;;; H7 n7 W. Y: b, O0 P8 J
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;; Initialize the display by giving the global and patch variables initial values.9 @$ e$ J$ @) K2 q/ n
;; Create num-cars of turtles if there are enough road patches for one turtle to
9 b0 y) B* z4 S; ^9 D;; be created per road patch. Set up the plots.5 r6 D5 k) H8 @% h/ M& R" g. x
to setup
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setup-globals+ t# V1 I$ b0 p1 w
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;; First we ask the patches to draw themselves and set up a few variables
) f' o0 x- ]2 h9 U setup-patches/ w+ K3 w/ ]3 Z+ _; s4 K, x! F
make-current one-of intersections0 `( t- {! [8 O- i
label-current- E3 g( s4 R6 Y
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set-default-shape turtles "car"* S& |! ^5 G/ W% K! `
9 S1 W+ r3 D9 g% ?- G9 A if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of ". u# U6 a- D ^: i! w* F. W
"road. Either increase the amount of roads "
; Z% K, N4 `" a/ J8 e "by increasing the GRID-SIZE-X or ") t' r1 a T( e( D/ o3 w a
"GRID-SIZE-Y sliders, or decrease the "
% K* o. \; J1 n" p "number of cars by lowering the NUMBER slider.\n"
7 `: G6 ?$ N$ K* T& b5 H! }# s0 I8 t "The setup has stopped.")
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( I& C8 Y+ J! d, S3 k+ d6 y: a ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color% J3 C0 H+ {# z
crt num-cars I- y4 x; a0 z& A. J. H9 u+ \1 }
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setup-cars
7 T6 G. [5 |' b' t1 V+ W: B) L set-car-color
$ G) h) ~" I/ w& v record-data
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4 a6 |# @* t- h! ~: C" R. u0 P* n ;; give the turtles an initial speed
9 n0 ]" i. }! j" u+ B {( u ask turtles [ set-car-speed ]' E5 U9 L; u' H! H b
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reset-ticks" a3 r+ j1 U0 M5 M( T& z
end
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{9 E. L8 _8 L;; Initialize the global variables to appropriate values% L2 z1 o& D% Y& Z; s
to setup-globals8 S3 s% i& O2 i9 L; s+ p4 Y
set current-light nobody ;; just for now, since there are no lights yet& \% A+ _. u6 ~! A6 \
set phase 0
# n4 ?- C6 i1 u/ x! | set num-cars-stopped 0
% m0 z1 Q/ y) n1 _: d5 N set grid-x-inc world-width / grid-size-x
9 ] @4 Y3 u$ ]. }( ?0 \% l2 i set grid-y-inc world-height / grid-size-y: q+ d3 W U, C+ v
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary& V% i, _ A b: f
set acceleration 0.099
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: a, V) d- K2 O;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
* \0 t+ o3 m2 w4 C;; and initialize the traffic lights to one setting6 i6 X* ~, n) i' \
to setup-patches( C; R. k" l# F) Z" p
;; initialize the patch-owned variables and color the patches to a base-color8 p v- Q" c4 c
ask patches
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: A9 z L$ k5 c( L$ e/ b set intersection? false
# i# H" j: F. [9 v* v* h) T set auto? false0 }& _, E: `& L% k) X9 F4 c/ l8 X! @
set green-light-up? true6 S" R" q& z$ z
set my-row -1
5 F1 U; B* G9 @( n4 | set my-column -1
d. F5 _! r8 [3 [# N0 L, S set my-phase -1. P: B4 m, X" W! ~9 M( u/ S
set pcolor brown + 32 c8 C5 u! ~1 `( C
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- ?2 x( \5 o) q# W7 n, \, B ;; initialize the global variables that hold patch agentsets8 B9 j# @- P% b3 p
set roads patches with5 Z" W4 G- Z7 ]" a0 F
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: V9 B" ^" Z# ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* ?8 o7 D0 K* G+ ^
set intersections roads with
; d: y- b) t3 I1 ]. Y4 U$ h6 ^ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
# @. t+ {; a) h, E (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]# j( K; ~+ K# j6 l* u S
setup-intersections2 U9 t6 P% I$ m/ R
end
9 E( d2 N6 o' y9 O9 [4 g8 K其中定义道路的句子,如下所示,是什么意思啊?; I" R: P x1 f/ r3 a2 [6 _. ?
set roads patches with! |4 i7 `3 Q. I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( u8 k" Y; ~( { c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: A$ W Q% P/ ?; o/ [3 h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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