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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。
7 t9 A8 m) x8 f8 mnetlogo自带的social science--traffic grid这一例子当中,
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grid-x-inc ;; the amount of patches in between two roads in the x direction9 V- d- Y1 `" s* H4 O* _$ Q
grid-y-inc ;; the amount of patches in between two roads in the y direction
/ p3 ^# O; m* T0 ^6 ]9 C acceleration ;; the constant that controls how much a car speeds up or slows down by if& T0 F. d% y/ V( W
;; it is to accelerate or decelerate
6 ^' b3 |; D6 X2 K+ U1 F phase ;; keeps track of the phase
, h! d- ] c6 x' G num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure, q. }7 N/ {( P3 n
current-light ;; the currently selected light
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: b9 j6 F# x9 j2 j8 G ;; patch agentsets* J l- K- I: o( u, b
intersections ;; agentset containing the patches that are intersections7 n( q; x1 }- }' M
roads ;; agentset containing the patches that are roads9 ?& l& L/ ~9 W5 o
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$ `% J; Z' a% p$ \- [+ ~turtles-own
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speed ;; the speed of the turtle
5 ?/ b, d. D# L3 x, ]" n up-car? ;; true if the turtle moves downwards and false if it moves to the right
( w7 |+ J3 v8 h, \6 @* P1 ^& L$ L wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
% \. h6 u& }# f5 S% ? green-light-up? ;; true if the green light is above the intersection. otherwise, false.
3 D( l6 R$ x A' l& Y ;; false for a non-intersection patches." f! O/ O; H, j7 p
my-row ;; the row of the intersection counting from the upper left corner of the$ c6 T8 }4 \, p* e
;; world. -1 for non-intersection patches.3 v$ S/ \$ S6 G1 l- c: H
my-column ;; the column of the intersection counting from the upper left corner of the
; h1 N8 F8 D& T2 v ;; world. -1 for non-intersection patches.- P: e+ a! a/ v+ J, x+ J/ e
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; @" v9 F0 R! ]; W/ Z auto? ;; whether or not this intersection will switch automatically.7 }4 v* S3 t6 {% u8 e3 X, |; o
;; false for non-intersection patches.
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) I+ k$ u# K; H S N;;;;;;;;;;;;;;;;;;;;;;
4 ], m: \" Z+ v( G$ G& S;; Setup Procedures ;;
/ ~; j5 n3 r; R, K" [# ]- |;;;;;;;;;;;;;;;;;;;;;;
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( w! V1 c3 A1 `: E4 s! V;; Initialize the display by giving the global and patch variables initial values.
6 ?; ^! k1 Y- u, j" y, Y: w;; Create num-cars of turtles if there are enough road patches for one turtle to ^! h- A/ E0 T* X3 `
;; be created per road patch. Set up the plots.) G: c9 S& O; u1 k4 E& H
to setup
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& P3 c/ T+ q# p" V) S setup-globals
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# \3 I: L' h2 Z- V# N0 |6 ]7 u6 ` ;; First we ask the patches to draw themselves and set up a few variables
, Y" M: j( t0 J+ ^7 }. u" S6 } setup-patches
) N d) n5 q1 ^5 a make-current one-of intersections
# t/ M7 A& w; O, u" J. u label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
- I7 C* v* @7 e1 z! b "road. Either increase the amount of roads "2 x# V1 m$ `5 z, [
"by increasing the GRID-SIZE-X or "- r8 Y5 d% L) i+ |; x Z1 l/ D) U
"GRID-SIZE-Y sliders, or decrease the "
1 R7 N0 h, H- m3 O* y8 E f "number of cars by lowering the NUMBER slider.\n"5 F, e5 u" g* E& X4 v4 ^: Z
"The setup has stopped.")/ \; X4 f' n8 {, v; Z8 C
stop
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/ \2 l, V( M9 C- u. R ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color0 P4 \0 S$ A) ?- c7 h
crt num-cars7 ~7 Z+ f6 c% g3 S% W
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setup-cars
9 m# Y( W8 I. A4 F+ ^ set-car-color
# {1 T" J8 ]7 e% T record-data
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;; give the turtles an initial speed$ n( o3 G& M9 w, J; o1 }
ask turtles [ set-car-speed ]: }8 j, Q# Q( L' G6 A" U8 @
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reset-ticks7 J3 e- b; U% g2 {$ F: F
end$ s# I0 G+ i- L
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;; Initialize the global variables to appropriate values' i( a s& n l4 T6 V' K, e! e* h& m
to setup-globals# o! ]" f2 y" ^: n q ]
set current-light nobody ;; just for now, since there are no lights yet' Z4 J% E2 L9 J; \
set phase 01 L" ^$ Y3 B4 h. }1 Z
set num-cars-stopped 0
* Z1 e) N8 G0 r Q5 q' g set grid-x-inc world-width / grid-size-x
- f6 }! _7 b R! _ set grid-y-inc world-height / grid-size-y
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. g* W" y' `: X+ C; B" F ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary; G, g) h; N* M' _- ?
set acceleration 0.099
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8 M# a9 N8 S# M& H& ^1 M3 z;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) X _/ Z5 {- R- S6 j/ p
;; and initialize the traffic lights to one setting9 V1 s w8 w+ |5 M* I1 T
to setup-patches: P2 [* {, C) F } |
;; initialize the patch-owned variables and color the patches to a base-color
2 M( a) ?2 D' a1 D; t ask patches- j0 c; C3 b" [3 K" Z: i1 J
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set intersection? false5 D' @9 ?3 e* S0 U" C3 A! }" C: p
set auto? false
$ a C6 {3 X9 s" F3 W/ ^ set green-light-up? true, r- x9 z$ l- D1 C
set my-row -1
# I/ J( Y2 S( b4 ~, c- H! m' c set my-column -1* G; g+ i* N9 g5 u
set my-phase -1# Q' n1 j* z' \+ b
set pcolor brown + 34 C; H/ I7 J, Q; G! U
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' |% \4 |& R5 n6 Z0 X! h8 [ ;; initialize the global variables that hold patch agentsets& M, P( n2 |4 W: g2 I: Z! ?
set roads patches with+ F9 e7 s! x6 ^* O1 b
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& e) C1 u C9 P (floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 G+ q3 H: Z9 H: x, L
set intersections roads with
$ T5 h" v( y% F% {; ^9 x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
9 a4 H- @+ c/ I/ U4 H4 p2 X4 f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' T, c& U" J$ o
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ask roads [ set pcolor white ]( \5 r( V$ B/ R( Y6 F2 f
setup-intersections
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1 [6 _1 q# h) z; y4 ?! L( T$ y其中定义道路的句子,如下所示,是什么意思啊?! [% [; D& W9 \- m
set roads patches with. B4 v! @! m) i7 p3 i6 \4 d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or( m: K) R( V: j4 B9 Y! o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]( v1 [0 j" Q3 o" e2 n/ r. s! d
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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