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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。
, c7 o7 |/ V: enetlogo自带的social science--traffic grid这一例子当中,! o5 C* h) e* C& e' @4 ?
globals
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7 v" x; q& I! M2 o6 [: }: a grid-x-inc ;; the amount of patches in between two roads in the x direction
3 y/ d* [6 j) }# b% w& u grid-y-inc ;; the amount of patches in between two roads in the y direction& [, D" t* L4 j2 E8 f4 U0 s; Q/ y
acceleration ;; the constant that controls how much a car speeds up or slows down by if
) W/ f& t0 Q8 k$ u- `4 j ;; it is to accelerate or decelerate
, }: [# S2 \% L* ~. h phase ;; keeps track of the phase
3 G u, `; U6 X* X num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# e9 P4 ?- b; D2 s$ @. H current-light ;; the currently selected light0 n' ^+ b9 }. ?- i8 y y3 [+ _
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;; patch agentsets* }; i Q8 F% J
intersections ;; agentset containing the patches that are intersections
; D: J2 t8 U4 p# ? roads ;; agentset containing the patches that are roads
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0 }3 H7 p6 W, {) u; v- oturtles-own
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speed ;; the speed of the turtle% Z% Q( z- O; K x5 C! o0 Q
up-car? ;; true if the turtle moves downwards and false if it moves to the right
9 M8 [* ^4 l- |; _ wait-time ;; the amount of time since the last time a turtle has moved" S) E- L% p5 X2 ^$ y! l: t
]
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patches-own
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9 b) H s% [4 @& c& M) A+ T1 o1 H intersection? ;; true if the patch is at the intersection of two roads, B) l' [/ b2 D
green-light-up? ;; true if the green light is above the intersection. otherwise, false." S( u3 _1 L/ t: F
;; false for a non-intersection patches.& ]( C( [, @, l* G
my-row ;; the row of the intersection counting from the upper left corner of the
1 k5 }- Q. t% Z Q1 b% t ;; world. -1 for non-intersection patches.$ m. w e0 N6 ^2 c- d$ |
my-column ;; the column of the intersection counting from the upper left corner of the, t3 J4 G# e4 j z' D/ o
;; world. -1 for non-intersection patches.% _# Z. _; Z6 ^
my-phase ;; the phase for the intersection. -1 for non-intersection patches.. S) W6 l6 U$ \
auto? ;; whether or not this intersection will switch automatically.
; {7 O4 ~/ ]7 G ;; false for non-intersection patches.
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( y, r/ U8 J$ i2 P8 d;;;;;;;;;;;;;;;;;;;;;;
* Q: ?& F% k- r3 i: ]" `;; Setup Procedures ;;
" h+ Y1 m& D& r;;;;;;;;;;;;;;;;;;;;;;
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1 C; J; C, s: w;; Initialize the display by giving the global and patch variables initial values.& X8 _# [: h' x& o& N% h
;; Create num-cars of turtles if there are enough road patches for one turtle to
+ t) L& @# C, ^& L# J5 a- w;; be created per road patch. Set up the plots.6 ?* T% v U! |' h: N
to setup
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setup-globals6 W7 W' d' v3 W' D% d- B
- Q' ~6 ~+ ?& @5 z, h$ r3 J ;; First we ask the patches to draw themselves and set up a few variables$ w) @9 i# F3 @" U" x
setup-patches
2 M `2 o" z- j$ @* e make-current one-of intersections
) K) v! V$ ~( }9 Z# r label-current+ e \( l( ~* b9 U' d/ a1 u
/ I. p5 @8 T! p0 K- f0 s% T8 a9 u set-default-shape turtles "car"
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if (num-cars > count roads)
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& ]1 N! u3 \/ t) i user-message (word "There are too many cars for the amount of ": o P8 [0 k( J6 F* a9 ?0 d9 E8 ?
"road. Either increase the amount of roads "
! h D3 m1 h4 j0 Y; T3 _4 g( }# j "by increasing the GRID-SIZE-X or "
2 N0 H6 c" W7 f* j5 |4 W' g! U+ ~0 C "GRID-SIZE-Y sliders, or decrease the " S; ^' i' p9 n
"number of cars by lowering the NUMBER slider.\n"
4 f1 z+ ]" y4 {" h' w) C0 ? "The setup has stopped.")
2 I/ W' ?9 C8 D* C# O* p9 a. [ X stop0 r6 f' [2 C4 G, e: ^
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 w! k0 T( V) U6 F crt num-cars3 |, p4 x6 k8 M4 a
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setup-cars" P# H* m/ u4 m: R$ T
set-car-color
+ Q; q# H% p. o record-data& H' T3 s8 }8 z' g, X+ H
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! C, w. [% Q7 t w m2 } ;; give the turtles an initial speed) X, C @) b! S# p1 u
ask turtles [ set-car-speed ]' \# y4 t8 t. K
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reset-ticks
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;; Initialize the global variables to appropriate values
F3 f# {( K# Cto setup-globals
9 T: B3 B: f" {! X% L( a) A set current-light nobody ;; just for now, since there are no lights yet4 I. c: V5 |8 f3 i
set phase 0
: a7 F i- X9 |8 J set num-cars-stopped 0! M* B3 G% l7 o/ k
set grid-x-inc world-width / grid-size-x
$ Q0 \1 z- Z$ G% n set grid-y-inc world-height / grid-size-y
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: o, j. {8 O+ {; Y ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
9 E1 V1 L* t* d/ ~, o set acceleration 0.099* Y+ i6 v: y; o4 D0 T+ v* F
end: \* F$ t9 @- }* L% K
% z1 [- X7 c9 `/ L;; Make the patches have appropriate colors, set up the roads and intersections agentsets,- Y8 ^: T$ L# d, H
;; and initialize the traffic lights to one setting
" d( G; W& {1 |8 g5 kto setup-patches
, \3 c" `9 I6 w ;; initialize the patch-owned variables and color the patches to a base-color
+ B3 |: h3 _" K- R( \- K* m ask patches3 k; K9 p: P, E3 X: T- C) t. e2 u
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set intersection? false7 G- U( t8 }" S. \0 J
set auto? false9 k' G' W/ T' D3 r; m( Q2 G
set green-light-up? true( i! c( N" W4 {' S6 s) [. U2 M# P
set my-row -14 Z3 C, ~1 m; J4 [& s& w( U
set my-column -1. @3 ?2 M# V. f0 l: R5 m! M
set my-phase -10 T, S, |5 q% L3 O) J
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets# k/ u# [5 |/ b' J" _- r
set roads patches with
. \0 e w) i8 F, s5 y' g [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 N. C2 n5 K6 } (floor((pycor + max-pycor) mod grid-y-inc) = 0)] \" h1 o6 d/ K7 F. ]# R% e
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 e! d- ^# j! [( K
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ask roads [ set pcolor white ]
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end$ @4 h: f' f0 R/ Y1 o2 z9 w
其中定义道路的句子,如下所示,是什么意思啊? b- Y+ b* H, k, L
set roads patches with
0 G5 \7 q( T) x% I [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, w5 ]. G& H; i, R+ y4 c5 k (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" Q n2 @1 R: I* H- T* N7 R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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