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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。
2 t1 J* q6 N1 ~6 O5 _netlogo自带的social science--traffic grid这一例子当中,: M3 [2 K+ e! r$ T8 T n
globals" l5 {7 w+ x6 @" B
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0 P) v$ K! _* D! E/ |8 {/ X. T grid-x-inc ;; the amount of patches in between two roads in the x direction$ Q) T* q0 y: S+ \- h
grid-y-inc ;; the amount of patches in between two roads in the y direction
5 @2 ~+ H; r. q3 S& o% {6 p acceleration ;; the constant that controls how much a car speeds up or slows down by if- C; y( k- J4 ?
;; it is to accelerate or decelerate
; Q {# P B8 [+ X1 U phase ;; keeps track of the phase
+ I- U) J( [) ^ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
8 l8 W3 g5 {, J6 m$ b9 u current-light ;; the currently selected light
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8 k* V3 j$ c+ \, F6 q ;; patch agentsets: w* Y0 U) B0 x% l" J. I: ?3 s0 P
intersections ;; agentset containing the patches that are intersections( }* v% @+ J9 Z# a9 D, N2 s/ V
roads ;; agentset containing the patches that are roads
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/ X7 ~4 T) B3 X! W. W* Uturtles-own. S) |1 t, A" G3 p! O+ i1 H" c4 R- `
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1 H' N. k+ Z i5 s- s8 j5 e* @ speed ;; the speed of the turtle
7 v$ B8 {# {& K up-car? ;; true if the turtle moves downwards and false if it moves to the right
; g: N; ?+ P5 A% z+ n9 p wait-time ;; the amount of time since the last time a turtle has moved5 V) k- u4 j5 G+ g; |& ]
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. Z$ X, A4 \3 e/ Hpatches-own1 P# M- e0 N" c
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5 y) f8 I) x# } T5 F9 f9 y, z/ |& z7 C intersection? ;; true if the patch is at the intersection of two roads
- t, F/ J6 l5 Y7 Y, d' V# Q green-light-up? ;; true if the green light is above the intersection. otherwise, false. v* u1 X3 e6 p: V p
;; false for a non-intersection patches.. b: _3 P% v: l1 d. b. }; u& L3 G: P
my-row ;; the row of the intersection counting from the upper left corner of the
0 Z0 a5 k5 o2 }. H) x) x ;; world. -1 for non-intersection patches./ o$ h* u$ x: R$ Q- s9 k
my-column ;; the column of the intersection counting from the upper left corner of the
7 k! Y9 ^' g4 Z R9 v7 A ;; world. -1 for non-intersection patches.7 H& W! ~1 @# u/ R: X
my-phase ;; the phase for the intersection. -1 for non-intersection patches., j% f3 C ~. z m: M) @$ q$ g+ H- g
auto? ;; whether or not this intersection will switch automatically.! ~4 k% V- G. a. E
;; false for non-intersection patches.
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F$ k8 I8 B+ B; v;;;;;;;;;;;;;;;;;;;;;;
, O" I8 P' R' c3 i7 S, ]) }& N8 s;; Setup Procedures ;;( s9 G; z( V! L
;;;;;;;;;;;;;;;;;;;;;;) `. T8 M( V9 A- }$ z* g& F
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;; Initialize the display by giving the global and patch variables initial values.* g1 ?6 s% D4 w
;; Create num-cars of turtles if there are enough road patches for one turtle to
$ i3 D. Y: G$ Z# w) M; A;; be created per road patch. Set up the plots.
) @5 _& C: t) Z0 }7 H ito setup
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setup-globals7 M! V. s, N9 g& u6 J
; C3 w' c' }2 t0 R* m; H ;; First we ask the patches to draw themselves and set up a few variables$ N* D: L/ H2 }" `1 u) D
setup-patches5 O; K- v: ~# }! B/ i
make-current one-of intersections+ X4 [8 I* k% D) w% t" h
label-current
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1 K) q+ L* z2 P- X q0 U; c set-default-shape turtles "car"1 A- Y0 j2 t/ T7 x$ F" C+ a
' F0 x7 `6 }. ^1 l% c- R if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "+ i( r: {+ k U3 `6 R& |' \
"road. Either increase the amount of roads "& W! |% M& T8 q( D
"by increasing the GRID-SIZE-X or "
" o) l7 Q$ c6 {' K% W: @% y6 k "GRID-SIZE-Y sliders, or decrease the "
9 S; l+ Z5 _+ \$ }% ^0 \9 b0 S "number of cars by lowering the NUMBER slider.\n"* A ^8 t* u5 j6 d
"The setup has stopped.")
: M4 Y, t$ J( ?7 F# H( d stop
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* G6 J; y4 C) `1 d ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color; y( d6 x& l1 q2 K
crt num-cars
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setup-cars
/ ]$ _# r" b- k# w2 r set-car-color2 U8 o/ l7 I6 S. V
record-data
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;; give the turtles an initial speed0 }& K4 ~7 J' S2 g; D! f. j2 h
ask turtles [ set-car-speed ]! I5 S9 C4 H; C# a" {$ u
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reset-ticks
8 Q1 S/ _9 ]" R# n; _" n5 C% C1 Y' J) Yend
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! L# s G: {# }' ^% U; l# L;; Initialize the global variables to appropriate values+ n3 u! G+ p( u1 c8 F
to setup-globals6 b, k& B* H2 A, i
set current-light nobody ;; just for now, since there are no lights yet& h7 v0 `. F$ R M7 t- b# f
set phase 0! W: L d4 f6 m: R
set num-cars-stopped 0* h) }+ o+ G1 d8 H
set grid-x-inc world-width / grid-size-x# ]6 x# h& b* N. Z! u8 X' D/ v
set grid-y-inc world-height / grid-size-y
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# }6 Q! r8 G+ ?5 ]0 x, f1 Y ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( U* |1 r% _* C2 ~0 n% | set acceleration 0.099
, r: R% A' i+ @8 [5 d$ ~& Eend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' T' x3 }) r& t6 F;; and initialize the traffic lights to one setting2 `" h' D- o, D) R6 n
to setup-patches
# g% [2 f# z7 l# u# z. Y7 p: _ ;; initialize the patch-owned variables and color the patches to a base-color" h/ C/ Y3 S) Y2 S/ B6 x9 ^
ask patches
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! w+ { u/ @1 n: u- t* h set intersection? false
2 s1 K6 [# L, c+ B1 ~4 b! F set auto? false) f' M% Z+ q" Q, q4 x; R
set green-light-up? true+ a9 A- ?! z* t
set my-row -15 t( C" J7 R+ h- B' q
set my-column -1+ s- G0 }6 S; }: a- [
set my-phase -1
8 ^- E7 n$ c- N$ o7 x set pcolor brown + 3% |. S; ]- j6 k3 {6 _7 @
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;; initialize the global variables that hold patch agentsets
8 K" ~9 Y+ F* g0 U. o: t6 a set roads patches with& t/ d) l- m( J% z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. I. F& o8 g+ q8 \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
X: o4 @$ \5 \' b4 m5 U$ @9 d( t' I3 L set intersections roads with
( D2 r) V; h( `; j& W4 E& D7 t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and' A* U- y2 Z0 q j0 d2 I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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( p. a+ E5 b7 j7 U# [ ask roads [ set pcolor white ]+ g0 D- u# F p6 M
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
* N# N/ F2 U- X set roads patches with
( M7 a! b$ W" h+ r5 @. R3 J2 ^6 u6 m( n6 N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
! A2 Z+ ]8 f7 Z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 w8 D% z6 X' e4 v4 h0 s, n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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