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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。! \. c) L$ g5 Q
netlogo自带的social science--traffic grid这一例子当中,
" a! S' v# n3 W% tglobals
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& L/ a: }* {$ M$ f( g grid-x-inc ;; the amount of patches in between two roads in the x direction
8 y7 {5 j2 f! N5 \3 |& T( q1 p grid-y-inc ;; the amount of patches in between two roads in the y direction
4 Y7 _) d8 {* \% Z+ z* W8 x$ E9 F acceleration ;; the constant that controls how much a car speeds up or slows down by if
& m: t7 r! s% q- O ;; it is to accelerate or decelerate
/ D+ @( C+ P" x( M# d phase ;; keeps track of the phase9 d0 F1 C; b5 I' J' m! w
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure6 v- w- A! J0 S$ n5 d1 Z
current-light ;; the currently selected light" y. f5 p( c' J* A1 V
+ P7 j% K! ^8 z2 F* _1 j ;; patch agentsets
4 H0 |6 B" U* G) X intersections ;; agentset containing the patches that are intersections
7 D) _. ~" S4 `0 q s0 X# a! H roads ;; agentset containing the patches that are roads
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turtles-own
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: ?7 i F, S; c$ q2 U8 N speed ;; the speed of the turtle( h! j. w9 G3 m6 K
up-car? ;; true if the turtle moves downwards and false if it moves to the right6 [/ Z8 H6 d7 l1 Z; K# i" ~+ K
wait-time ;; the amount of time since the last time a turtle has moved$ A" y8 h2 e( Q% t3 B. h0 N
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patches-own
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8 f( M8 h( B. \ intersection? ;; true if the patch is at the intersection of two roads% a. T: r: e" G+ `
green-light-up? ;; true if the green light is above the intersection. otherwise, false.- B' w9 ~ \* s/ O7 w2 r3 A8 }
;; false for a non-intersection patches.8 N" M, z6 a, S0 ?0 O, q, I
my-row ;; the row of the intersection counting from the upper left corner of the8 b V0 ^7 N- ~
;; world. -1 for non-intersection patches.
+ E }8 X8 e0 s+ n my-column ;; the column of the intersection counting from the upper left corner of the! n6 O$ U# L' I- i( i
;; world. -1 for non-intersection patches.
0 f+ q, M' l2 ]; g) N1 z my-phase ;; the phase for the intersection. -1 for non-intersection patches.0 n4 O m! z( M2 B* ]! Y, e
auto? ;; whether or not this intersection will switch automatically.
2 a2 z4 {9 C( W6 A7 L ;; false for non-intersection patches.& S' ]" S5 \6 Y6 l
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) D+ H1 h2 e _% A$ M0 k+ w;;;;;;;;;;;;;;;;;;;;;;. v. t3 J8 l2 w
;; Setup Procedures ;;6 x, d% `. s7 U2 k/ ]
;;;;;;;;;;;;;;;;;;;;;;
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1 b0 I E+ E5 y; J" z" A;; Initialize the display by giving the global and patch variables initial values.( @8 ]9 v, {8 U1 e
;; Create num-cars of turtles if there are enough road patches for one turtle to
; n& J* S5 k0 `2 X( b4 k% m;; be created per road patch. Set up the plots.
5 K2 l- Z, u# ~to setup
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" E6 Z& }0 J1 g/ A- h setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
3 E5 y. H; H" u% ~ setup-patches. j% }( B6 R7 @
make-current one-of intersections
4 u% E* L/ p# M8 G! l2 W label-current
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" @, ?, X( g6 z. z8 \ set-default-shape turtles "car"
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" f/ y7 F. i, H, T. \8 z" E if (num-cars > count roads)4 B! C/ w: ^, p8 y$ o
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user-message (word "There are too many cars for the amount of "
" p( x% Z8 W( D "road. Either increase the amount of roads "" E* ?; w% c! f# S- m& g
"by increasing the GRID-SIZE-X or "
' m# Q. [8 w/ ?8 b, i "GRID-SIZE-Y sliders, or decrease the "
7 ?1 v! Z+ m2 o "number of cars by lowering the NUMBER slider.\n"
. \5 W/ {/ p4 ~% g. @: W+ ? "The setup has stopped.")( {4 R4 ^& @; r
stop
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0 y' {1 f" S& n" U9 {' G# {( X ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
}5 N9 Q |( s( l$ a, R crt num-cars9 c8 X* N& E5 y7 s8 M9 p
[
' ~* a1 t! E' M2 g4 f setup-cars
) W" i% M- t& ~ set-car-color
: w- g$ j' o8 Z( y$ f4 t record-data+ g. k" Q% X# h
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! Z1 H& {) o4 Q' X& M( ?: t ;; give the turtles an initial speed
' {' ~; b5 e4 B ask turtles [ set-car-speed ]
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: S; O0 e5 L- \0 X( G8 f' { reset-ticks; R4 o% j; {0 x0 k% v% u5 Z
end% g) A& b5 [. C9 v- z+ X% f
: G! m9 r; X$ G;; Initialize the global variables to appropriate values
7 ?4 P A4 b8 w+ c& P. }to setup-globals& \+ p+ ?9 }; i* P$ `& t% X! e
set current-light nobody ;; just for now, since there are no lights yet- m7 B3 M3 d6 c1 `7 ]0 f
set phase 0: l a9 x" [2 d) F
set num-cars-stopped 0
3 Z( {: S/ J9 t- |6 g, e set grid-x-inc world-width / grid-size-x
; y, z: Y% U9 e: v/ f& S set grid-y-inc world-height / grid-size-y
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+ f0 D+ b! c. u ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
* S( Y$ Y" ~+ x2 M! f9 A- a# _4 A set acceleration 0.0996 H/ Y8 f# Z6 c5 a, [! q/ ~5 I
end8 ^1 A& c7 ~$ n0 a9 ]
7 Q: U8 Q" r; n1 D1 Z- O% i;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
/ v1 P$ B+ M0 q( E* V;; and initialize the traffic lights to one setting6 o/ S9 L" `( P. `+ Q
to setup-patches& z7 b0 r$ V% P$ y' j* s
;; initialize the patch-owned variables and color the patches to a base-color
$ l. S( w1 P! e- I ask patches+ F% ~# `! @! C; i3 [& z- a
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set intersection? false" K. {. e o5 Z7 _1 u
set auto? false3 x7 A) R8 G, l
set green-light-up? true
6 n, z6 |, y% M: _ set my-row -1
0 S: f2 l6 F, N$ u set my-column -1
& v+ Y/ m1 @9 q7 \$ k set my-phase -1' @9 W. s, g9 t, c* y
set pcolor brown + 39 Y: X# l( \9 A% C# |
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;; initialize the global variables that hold patch agentsets! G0 n! M& |! ?
set roads patches with& z7 s+ r4 N& A* ~/ K* H
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' g1 I/ a9 M' m4 P
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 M' j0 f6 Z( Y2 [ set intersections roads with- U1 `: y1 I q( k' u, C
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( x+ h+ V# F3 v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]- v. R$ O( r& F4 r
setup-intersections: z: Z ? q6 W% N2 V. Q
end
# W' F0 }- {* W5 T7 B+ p其中定义道路的句子,如下所示,是什么意思啊?% o! e/ e: {4 [; x: ?$ x4 ^3 G
set roads patches with6 Y. |6 J' m4 D1 f$ n1 j
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 n/ o9 A0 Q1 p# P: A8 N5 u2 c
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 q* H0 I. m; ^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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