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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。
* ~ D2 t# I, cnetlogo自带的social science--traffic grid这一例子当中,
% x' K; m3 ?' F4 x, b: ?+ a$ z5 U" ^globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
4 S3 l) V+ [2 N( i$ I grid-y-inc ;; the amount of patches in between two roads in the y direction2 k' m# u& ^5 j- A
acceleration ;; the constant that controls how much a car speeds up or slows down by if
: D0 A. n1 X" D ;; it is to accelerate or decelerate
\5 U" ?% a( O( r2 K% E' z8 u. L phase ;; keeps track of the phase
5 ?2 n6 U1 w t0 K# u3 o' F num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
" f v( ~) u# y R current-light ;; the currently selected light
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;; patch agentsets( r* b! S3 B! D3 B3 w8 Z
intersections ;; agentset containing the patches that are intersections# W( C7 g( Q! _" [
roads ;; agentset containing the patches that are roads
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2 F" {, v- t! I( O/ x& u3 x5 X bturtles-own# _5 ]/ }( s: }; b7 f: w. z M
[
! u: S2 `5 N- U4 j! R0 Y speed ;; the speed of the turtle7 y0 h0 q0 R T9 m" T
up-car? ;; true if the turtle moves downwards and false if it moves to the right
# W/ e7 X9 P$ G wait-time ;; the amount of time since the last time a turtle has moved
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% F$ R: \9 W% B* Hpatches-own) i4 m+ r6 t8 e: z0 j
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intersection? ;; true if the patch is at the intersection of two roads
- [+ g& e( x1 x$ a/ B" |+ | green-light-up? ;; true if the green light is above the intersection. otherwise, false.& y) T8 o5 ?* l* `. c# \4 S* a
;; false for a non-intersection patches." c# p7 c% L. h7 H8 \; j7 C
my-row ;; the row of the intersection counting from the upper left corner of the; N: n N& B# `1 B- W# A# |' f) y
;; world. -1 for non-intersection patches.% ?3 g. j) g2 b; `0 g6 w
my-column ;; the column of the intersection counting from the upper left corner of the, T6 U# P4 ?% T2 H( i' P; o3 n
;; world. -1 for non-intersection patches.$ U6 x: E) k/ o
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
: L1 h. D( |" J auto? ;; whether or not this intersection will switch automatically., I% h8 r# O4 x3 _" U+ W$ G5 _
;; false for non-intersection patches.+ @/ b* K2 _& ^1 d
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;;;;;;;;;;;;;;;;;;;;;;
: u# D0 `6 @" r! n3 a! C;; Setup Procedures ;;* _/ s/ o# ^0 S2 m- k2 ?4 F* w
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;; Initialize the display by giving the global and patch variables initial values.. Q2 u4 I! ?7 }/ j
;; Create num-cars of turtles if there are enough road patches for one turtle to! a, j( z0 z0 h
;; be created per road patch. Set up the plots.( u5 r1 M7 r+ r. Y
to setup5 u" J( ^6 f% \
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setup-globals1 M+ ~ s* ]4 s3 s- B
, x0 e" l" \: A% V ;; First we ask the patches to draw themselves and set up a few variables
1 _4 R+ ~# ?( F B2 w& Z3 ?0 M setup-patches. U) w) Y6 q3 F1 }/ K
make-current one-of intersections
Q, m' N; r1 Q# o1 S+ a4 n label-current
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0 I& @# H6 P. D1 }* Y' M set-default-shape turtles "car"$ _9 N# J/ S. \5 k# K- [& R
2 M* y! p' y9 x6 h D if (num-cars > count roads)
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! A2 h, C2 C: {3 T user-message (word "There are too many cars for the amount of "
) V3 ?2 H. \ u ? "road. Either increase the amount of roads "+ _* Z. L5 E$ O; g$ W* g+ G/ X
"by increasing the GRID-SIZE-X or "
. w/ e# k( b2 g2 E& P& |9 P "GRID-SIZE-Y sliders, or decrease the "5 V% U; _9 l+ H1 U8 A* u
"number of cars by lowering the NUMBER slider.\n"5 \! h" R* A, Y3 \$ c
"The setup has stopped.")$ G/ ?) T" r5 L( Z
stop% \: [& j4 E3 s2 j! Q
]
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. S! G: m. v5 K ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 m2 z* \! F2 e" h) }+ | crt num-cars
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# b& G3 m. I4 `- Q/ |7 D1 z- t0 K setup-cars
# T; B+ r' d8 Z, | set-car-color
6 T d9 X1 U+ a0 O, i' v* Z# l( M) z record-data
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/ M7 W1 S3 P/ Y+ f2 a ;; give the turtles an initial speed& g, P0 d, E. C
ask turtles [ set-car-speed ]
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reset-ticks
9 p0 G9 c' W6 Cend
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5 b- |* c" v" N;; Initialize the global variables to appropriate values
: G! e5 Z0 s# T* q) y$ [to setup-globals1 k# z; _- e3 ^
set current-light nobody ;; just for now, since there are no lights yet
d# Y' i9 p6 I2 e( O set phase 0
" ^7 F- M' C& r" K( O3 p set num-cars-stopped 0
8 t1 X% ?: R6 H. D# b0 M set grid-x-inc world-width / grid-size-x0 E) _- V) B: G$ ? D- h" s
set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
8 I' Y# d4 V7 }! k5 c | set acceleration 0.099
) k/ @; b9 G Q5 G7 nend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) ~' r Y* H b! d6 R7 n1 _5 Y
;; and initialize the traffic lights to one setting6 \" u$ ?$ t: R$ u
to setup-patches3 [; J# b" [/ i
;; initialize the patch-owned variables and color the patches to a base-color( c3 b% ?3 E+ C) ^. P* x0 k
ask patches, r7 T7 r; ^' O+ a7 l c3 _1 | Q
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set intersection? false- B' d8 x/ n8 D- L! s" _
set auto? false
, e% c s" L8 M* I* C, ~$ I' w set green-light-up? true0 J3 h2 w2 {" d Z
set my-row -1; v; R. p1 J& M: m- U, l
set my-column -1
6 F6 @( x, P) _: `1 B( o% b set my-phase -1
3 f' X( A9 W9 Y5 @ set pcolor brown + 3
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) @% V a8 t4 I. g/ p$ U ;; initialize the global variables that hold patch agentsets# J) j% F2 R z/ B: W8 }. N
set roads patches with
% @6 z5 `3 R* G [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* [6 u7 D7 g1 ?3 O; y+ _0 p (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- x4 x( d ~. }( j set intersections roads with' C% o+ W2 L1 ~( C% ~
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
9 P) X0 u2 L) s' G0 y, j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 Y$ a- n! R- X u) U+ w* N* p
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ask roads [ set pcolor white ]
7 L7 p2 |: E$ A) q, R: Y1 Y setup-intersections
5 g. U s4 c5 Q6 q* ?3 ?; Q; Tend) }* z# _9 n2 ^$ v5 R" V
其中定义道路的句子,如下所示,是什么意思啊?0 \! |) a @9 u4 i8 c5 G
set roads patches with
9 | @7 p6 _0 H; t2 s% d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
b- i( X0 o+ m- E. A( m (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* K8 o6 \7 a5 t, j
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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