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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。
, a1 w8 r, k( X# o, K8 knetlogo自带的social science--traffic grid这一例子当中,
& `, D8 j. R$ Y" Vglobals
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* O1 q! Y8 Y4 L9 q4 ~2 d0 S grid-x-inc ;; the amount of patches in between two roads in the x direction: s+ Z# S8 E' `9 i) e
grid-y-inc ;; the amount of patches in between two roads in the y direction
N% |4 K! ~# x! a acceleration ;; the constant that controls how much a car speeds up or slows down by if+ e. x6 d; A5 l3 {5 o }! M# y8 i
;; it is to accelerate or decelerate! D' u# F' s4 Z! m1 S
phase ;; keeps track of the phase
. {$ q6 |3 P2 K2 J, s: {; f4 B num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 I5 i* f& f. G5 r4 f# s& `, D& V current-light ;; the currently selected light& P, P! ?) A0 H
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;; patch agentsets
% t# {1 `: z" z# G4 s intersections ;; agentset containing the patches that are intersections% o8 P* d- m9 J' |4 _1 M
roads ;; agentset containing the patches that are roads% }! f4 Y6 T8 j m# m) e8 [
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turtles-own4 n h8 w, k2 o; L& _ ]3 I
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speed ;; the speed of the turtle2 H1 T: i* A" c4 }. d3 r
up-car? ;; true if the turtle moves downwards and false if it moves to the right
* ]& F% ^; ?. i wait-time ;; the amount of time since the last time a turtle has moved
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patches-own, m4 Q2 E2 |# V$ l0 q, w
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5 Y6 {4 V- C, l# x3 g$ D$ t, I7 x: e intersection? ;; true if the patch is at the intersection of two roads
) K# g7 Y4 b: m R x4 C; d* I0 w green-light-up? ;; true if the green light is above the intersection. otherwise, false.) [; i* e" Q0 g0 v4 G; T
;; false for a non-intersection patches.% o$ N2 p# Z* u; j/ I4 ?7 X! Q
my-row ;; the row of the intersection counting from the upper left corner of the) P* i6 I) X: D* C, b6 s/ _! ]1 \! w
;; world. -1 for non-intersection patches.
, R, j/ M t+ S my-column ;; the column of the intersection counting from the upper left corner of the
! X! h" D4 Z# i, s0 M ;; world. -1 for non-intersection patches.. t! C3 [- F" I6 y# B
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
3 ?; C% d- q3 L. m auto? ;; whether or not this intersection will switch automatically.
6 u2 S7 y& O: A: p' F1 B3 u% N ;; false for non-intersection patches.
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! y" n; h+ f% ~ k- S;;;;;;;;;;;;;;;;;;;;;;
/ F8 _2 c4 Y( \;; Setup Procedures ;;8 A- ^8 |7 V+ N! ]4 [) S
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6 k! b1 r. s. Q' @ K1 r;; Initialize the display by giving the global and patch variables initial values.
- w. e1 |4 F I, a& w6 Q2 W;; Create num-cars of turtles if there are enough road patches for one turtle to
+ l- P/ z# S% p5 t;; be created per road patch. Set up the plots.
7 x3 F) S% x- F. v" r: lto setup8 g; b2 V9 u/ ^( k" t
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
0 V# G! z8 x, [; D7 M; \& ^& ^ setup-patches
1 O+ S, E" [9 q' r: ~5 d make-current one-of intersections, }4 T. Y+ ]+ _8 k5 X6 ?. s3 |
label-current
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set-default-shape turtles "car": f9 v3 B0 C. U9 s3 J/ Z! W
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if (num-cars > count roads)
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7 V0 L: m0 v* D) H# v8 @) k user-message (word "There are too many cars for the amount of "3 N3 L; g! d( u9 C' T) U
"road. Either increase the amount of roads "
. Q8 n2 j0 P7 r4 I# S' y: w "by increasing the GRID-SIZE-X or "
2 f2 Z# L" H8 ?+ N- {8 C6 s( y: e- \/ a8 i "GRID-SIZE-Y sliders, or decrease the "3 P% }- M' ]9 p6 i6 G z; O3 T& D; z
"number of cars by lowering the NUMBER slider.\n"( E- {- k& Q3 V- M2 v
"The setup has stopped.")
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color7 S0 F8 V' q7 S6 g6 j. R
crt num-cars
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7 o! F2 r+ N( ~3 W+ C4 G setup-cars
% K+ j k# r6 @- S( L" K set-car-color
! Q, q. F x5 X8 Q# U record-data8 h, p& d( F" T5 d7 C
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/ m7 k0 O% n( t2 u, x1 u5 A: W ;; give the turtles an initial speed
. C. A5 R! z) L4 w5 y7 ] ask turtles [ set-car-speed ]- I4 l7 W3 X* Z% V' ?
( U6 d. h: x3 s' e y( }' [ reset-ticks
, o8 R5 C8 U* Oend
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: m- C* _4 r3 D;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet1 s& B* w8 K" ?, e
set phase 0* C" @7 L7 Z. S
set num-cars-stopped 0# t1 ^0 d- y. N2 ^
set grid-x-inc world-width / grid-size-x" p* L( }# u) P# _
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
* Q; y1 V" h8 _) ^ set acceleration 0.099
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: o/ x& G) ^9 y) R6 t;; Make the patches have appropriate colors, set up the roads and intersections agentsets,( s' m9 o) u( Z4 }
;; and initialize the traffic lights to one setting- f/ o: W N5 _( \" _
to setup-patches
/ T% h+ C* J0 ]% w ;; initialize the patch-owned variables and color the patches to a base-color
1 K/ K( j5 ]" Y6 R# t( ?- Z9 q ask patches1 V$ |8 u; ]0 V- p5 i
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; V% t3 c0 D2 v& \8 r* | Y9 k set intersection? false
2 I$ h% ~6 u8 D" f set auto? false
. d W# c0 x; W7 Q set green-light-up? true
# w2 p8 V8 ]3 F9 D& {$ @$ N! q* w set my-row -1
+ K: @, o; }0 { set my-column -1$ m9 l: Z# Y) |6 p8 r3 ]" u5 f |+ w
set my-phase -1
' j! k# E8 K4 d/ Z4 y0 [ set pcolor brown + 3* P6 q( y, B8 M$ I( P
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8 Z, p/ h* p z- d ;; initialize the global variables that hold patch agentsets4 a. q! ^, S& i
set roads patches with
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; B2 |. O% T1 Y' N$ } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 H+ t& F, X" K E. S, ^- b, P
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 g" Y6 o! N+ n* M
K o; o1 W+ K% F W/ [ ask roads [ set pcolor white ]) u6 ^- g( i, b; D; |" `6 k
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?0 y/ i' e( l4 K4 [4 Z: ^
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 H7 U5 \1 P3 b$ w
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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