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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。
. n2 V4 |; I& C+ Xnetlogo自带的social science--traffic grid这一例子当中,/ ^, U/ t# @1 r/ r$ u; `5 `& s8 r0 |$ e
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction! I D1 n7 X% W: w- d. ~7 O7 x
grid-y-inc ;; the amount of patches in between two roads in the y direction2 B. [. s6 D& Z6 U j/ J
acceleration ;; the constant that controls how much a car speeds up or slows down by if/ Q6 H1 b, n$ J& J" V
;; it is to accelerate or decelerate
: n7 `7 S: Q, D# Q s phase ;; keeps track of the phase ^# d. T2 n! {% N7 I! `9 z
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" @4 h- F8 g% B2 H9 \
current-light ;; the currently selected light
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;; patch agentsets. u$ Q; d4 s8 A, j) y
intersections ;; agentset containing the patches that are intersections6 A5 w+ z- U6 e, q$ w ]
roads ;; agentset containing the patches that are roads
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1 m2 H6 r/ y6 U9 |; j. `turtles-own5 f a* s! n+ E8 r7 x( k
[
5 ~0 F+ [1 e* p" S' r speed ;; the speed of the turtle
' X' }: _& G2 L' Q+ n& m up-car? ;; true if the turtle moves downwards and false if it moves to the right
4 U2 r4 n3 ^) R8 R G wait-time ;; the amount of time since the last time a turtle has moved; d- N1 H4 m% ~' a5 n$ Q% o
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
3 ^) z0 `- Y- q green-light-up? ;; true if the green light is above the intersection. otherwise, false.$ r9 l$ M& V* Z4 {- P
;; false for a non-intersection patches.9 v( |- {! ~* {7 q
my-row ;; the row of the intersection counting from the upper left corner of the5 ^ O. C J. ]5 F' L
;; world. -1 for non-intersection patches./ y% u$ f3 n2 P$ V. A
my-column ;; the column of the intersection counting from the upper left corner of the
& a4 j- `0 }8 b( v. B ;; world. -1 for non-intersection patches.
9 `7 F1 K& E9 m. ? my-phase ;; the phase for the intersection. -1 for non-intersection patches./ H8 x+ s; y6 X" f- d. n/ L( H$ {
auto? ;; whether or not this intersection will switch automatically.
" P Y! I/ ]3 `( ~$ ]% m9 s- |) \ ;; false for non-intersection patches.' \, s) k+ t2 e
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;;;;;;;;;;;;;;;;;;;;;;0 t. Y w+ w; b/ r& }5 D
;; Setup Procedures ;;
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6 J2 F* @7 ^. F. F9 h# G;; Initialize the display by giving the global and patch variables initial values.' Y# v2 M% l& q0 x/ \1 n, b7 I: N. p
;; Create num-cars of turtles if there are enough road patches for one turtle to
# ^4 p- j' x7 W5 e' D' ~;; be created per road patch. Set up the plots.
& n8 P" m) Y& I Lto setup
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# Y; d: s1 h/ q5 [, H, ^ setup-globals
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4 `+ P0 X# |, J/ o ;; First we ask the patches to draw themselves and set up a few variables
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( x+ _8 d8 ~" e: ] make-current one-of intersections( M# i3 |% [. e5 Z) f( [+ Y1 V
label-current
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set-default-shape turtles "car", @; J L4 C8 t- ~6 V* c% }$ M! |
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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 "; v' Y/ v3 d9 V$ Z9 x
"road. Either increase the amount of roads "
( N+ C$ |4 t" B2 }5 f "by increasing the GRID-SIZE-X or ": f G$ M2 x4 @" ~9 \( l# O
"GRID-SIZE-Y sliders, or decrease the "
?* F ^$ S: D: Z "number of cars by lowering the NUMBER slider.\n"
[% T% H) c, N: ]1 A "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-color
- D5 j( a$ }1 L7 ?8 r7 o7 f crt num-cars0 W: F# M0 P6 F/ z! X) N
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setup-cars
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1 ~ b) Q3 {& A$ {6 h6 ~ record-data' @, ]* b5 X8 E! `
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3 m+ X; g8 a+ U: D/ c ;; give the turtles an initial speed8 _. s; t( z& k3 f2 K
ask turtles [ set-car-speed ]
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6 y0 Q0 h: N; l. q" V; A reset-ticks
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;; Initialize the global variables to appropriate values' e3 I4 d% W3 s& w9 l
to setup-globals# B! R' X0 d+ h* Q* z- p/ e h7 G
set current-light nobody ;; just for now, since there are no lights yet
) Z+ B5 G k$ K" w set phase 06 A. L4 X' J9 G4 c8 H
set num-cars-stopped 0
5 s! v- z* g+ }6 E set grid-x-inc world-width / grid-size-x8 L! g! S( e1 ?) f3 v1 L' `, y2 g
set grid-y-inc world-height / grid-size-y& ?+ Q4 a& x" R9 ^4 N5 k9 L
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( I4 P2 I% ~# I# p4 n+ v$ N5 h, P% v& N set acceleration 0.099
. u% y7 A9 [- U1 ?# i& O* |/ d$ ~end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
l+ J2 K& h. [& x& x0 ?1 p;; and initialize the traffic lights to one setting- h/ E, k) T i* W- I) |
to setup-patches
' p- a! e" G& ?' C ;; initialize the patch-owned variables and color the patches to a base-color$ h0 Q+ B9 g, N S, S8 w! r
ask patches
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set intersection? false
# S) I& S& }0 g5 n0 y7 g" H set auto? false6 I3 `+ F, ^$ p. `) Y1 r; p: P) ~
set green-light-up? true& H, J+ q9 U: } U
set my-row -1, J# r4 f. z( E, n) U& ?; J
set my-column -1# y; n$ m B% f
set my-phase -17 a; C* x# I) J
set pcolor brown + 3
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1 z2 F! ]5 f: y% [3 A# ~% U ;; initialize the global variables that hold patch agentsets
: d! C4 \& H5 z } set roads patches with% x* f# f( n3 S( o! E% M1 J
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) d# o% O5 V, L* n. V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' x X4 B# @. u$ `% m) G set intersections roads with
& Q' S) p* F) G [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and9 ~0 _4 y) C) v5 }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end4 M9 x* t( c& H8 @
其中定义道路的句子,如下所示,是什么意思啊?+ J. a7 s) r- @) e
set roads patches with ^& B0 z4 k' d- Z6 }; y* t1 C
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 b* ^: \% ~ T4 c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ O' X: _6 u% V- y Y' M" j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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