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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。
- p( w, f( D$ T6 ]5 Cnetlogo自带的social science--traffic grid这一例子当中,+ a! s( T! S' G! ^1 g! l
globals
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n% `2 H, A- M9 [% d grid-x-inc ;; the amount of patches in between two roads in the x direction; g( _( S+ [" ^+ G. P4 y* L+ c( }: m0 B
grid-y-inc ;; the amount of patches in between two roads in the y direction7 X7 K5 w3 i$ D' e4 j' M
acceleration ;; the constant that controls how much a car speeds up or slows down by if
}) h, e t+ V- {6 ^, B" | { ;; it is to accelerate or decelerate
; T1 e! y1 M P I$ q phase ;; keeps track of the phase
. e. t* R0 K% E# { num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
; q7 i4 p8 f: i" ~' U+ N current-light ;; the currently selected light
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;; patch agentsets3 Z$ g# L z. i, i1 F" ~- {9 e
intersections ;; agentset containing the patches that are intersections
4 p( F; W3 D5 z0 P' Y6 Y+ ~ roads ;; agentset containing the patches that are roads& Q0 W8 o& A& d6 f# S
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turtles-own
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, s" Z" v& j& n+ X0 G6 L speed ;; the speed of the turtle; z* i; g4 I" C( a/ ~2 }
up-car? ;; true if the turtle moves downwards and false if it moves to the right
( c. Y3 M3 _# M9 J wait-time ;; the amount of time since the last time a turtle has moved- A8 I* m6 h6 x2 y# l
]
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8 d; x4 n* s: J0 zpatches-own
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intersection? ;; true if the patch is at the intersection of two roads
' y- q2 E4 F% V! l: i1 {' K1 D* j green-light-up? ;; true if the green light is above the intersection. otherwise, false.: [' { X8 m4 w5 [" E: g
;; false for a non-intersection patches.
7 c. n4 \; M# i* E o m my-row ;; the row of the intersection counting from the upper left corner of the( q0 R1 h. z0 U$ ]
;; world. -1 for non-intersection patches.& U1 J, F# @) t
my-column ;; the column of the intersection counting from the upper left corner of the
' A1 Y- i( s/ E0 M" \ ;; world. -1 for non-intersection patches.
8 K5 w9 D/ B3 S5 j my-phase ;; the phase for the intersection. -1 for non-intersection patches.
$ v2 Y' c# Y, f2 h- M auto? ;; whether or not this intersection will switch automatically.
3 V$ v0 e* H- V9 u" o7 h$ U' Z/ K+ @- m ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
0 C5 `, K. b. a;; Setup Procedures ;;8 r2 ~; Y4 \8 Y
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;; Initialize the display by giving the global and patch variables initial values.
8 M5 Q C2 c, Y% g;; Create num-cars of turtles if there are enough road patches for one turtle to1 n& ?. v" ^, k' S4 V% x0 f9 V5 F
;; be created per road patch. Set up the plots.7 v T2 f* u( K" w, v- A3 a
to setup6 h; W! |' P$ w7 I# s, R* Q
ca
4 n1 u; w% r5 c) r8 M5 K# J setup-globals
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$ }2 H9 P# t$ s ;; First we ask the patches to draw themselves and set up a few variables
# P* Y8 l3 g5 t: o setup-patches
# f* V2 W8 y; C" u% M x make-current one-of intersections% R( M* ~: t2 q6 D1 w
label-current# k+ f* @ d, M: L+ l( `7 g
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set-default-shape turtles "car"1 z/ Y3 c2 }4 Z6 \2 m
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if (num-cars > count roads)
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: B) {; [* Q$ T4 J9 i( { user-message (word "There are too many cars for the amount of "
i( J, L% Z4 c0 ?% | "road. Either increase the amount of roads "
$ d6 f0 ~) E5 v7 E3 h* J "by increasing the GRID-SIZE-X or "
/ t0 A' f# N4 L "GRID-SIZE-Y sliders, or decrease the " u e7 P( V( S" G/ h( }
"number of cars by lowering the NUMBER slider.\n"% H B) }- K' X
"The setup has stopped.")) f: h9 I1 b6 Z# _0 m0 h; Q
stop# T. F/ E7 A$ E9 R4 d3 \7 c
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" f r$ b, r1 E1 D7 S ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 |+ [4 g7 [ C9 a4 G `7 y crt num-cars
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setup-cars
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record-data
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;; give the turtles an initial speed
: V, [# @4 {2 W( e ask turtles [ set-car-speed ]# m) w3 M; W5 M7 ]$ I/ |% U& q
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reset-ticks2 O6 o* U. G% ~0 M
end* _- l4 t4 t+ O/ k3 W
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;; Initialize the global variables to appropriate values
1 M8 J4 S# @2 ?/ ~1 Wto setup-globals, M. W4 B- o) T+ C& ]
set current-light nobody ;; just for now, since there are no lights yet
0 X- ^" N( I* k. R; B- V+ \ set phase 0
. g9 D: Q& e' }7 N* Z8 K0 r set num-cars-stopped 0) x1 ^4 M! z! D5 I7 W* L
set grid-x-inc world-width / grid-size-x
9 ~2 s( O3 ]# O0 z: ] set grid-y-inc world-height / grid-size-y& B& H! g( r; J! M& ?3 E
0 A% h0 S, a1 {1 H( W# j! C ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary- ~5 E3 }3 `, {( c4 ?/ ^' n
set acceleration 0.099
7 c( I. V/ f8 m5 X7 Dend' |" b' Q. D) O, @
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
9 S; w% h4 y; q- u4 s1 ~0 p;; and initialize the traffic lights to one setting( D8 e/ Y2 X9 D* `
to setup-patches: k6 `& |5 I% u! x4 `7 V0 D! H
;; initialize the patch-owned variables and color the patches to a base-color2 d3 l7 K$ L+ |" j
ask patches
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set intersection? false: t# K/ Y# K9 y: h& F
set auto? false V9 t7 w" I9 _- w& Z# @5 E7 N
set green-light-up? true' m9 C0 @4 o3 A4 \# K
set my-row -1
8 b: Z% ^1 V: {9 F2 h* P' Q' o set my-column -1" @; R3 I! z: M/ Q( G
set my-phase -1& s$ ]% n# {9 d1 p- [" k& B
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets1 A c' L& v {! K5 f
set roads patches with& I# o) _0 z" r6 Z! m( N& ^
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 ]% c* ]7 g: }5 m+ { (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" U7 J. A0 `/ p; V& `9 r set intersections roads with0 D0 M6 D+ x2 |& k' d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
& c6 m0 K+ d% ^! l% c9 d (floor((pycor + max-pycor) mod grid-y-inc) = 0)], r9 Z$ V3 v+ F- M+ K! I. W: ]1 Z7 O! P
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ask roads [ set pcolor white ]
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其中定义道路的句子,如下所示,是什么意思啊?
5 f5 J) Z3 Z& H/ z+ f( J set roads patches with
, U; y# v. B& d5 [% I2 L q' e$ Q. u& z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or t* t( W) ~5 r2 T m- t3 H
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& ]" h7 m4 y. E1 Y1 F/ `6 O! E
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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