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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。
1 t7 r Q; Y, n3 | t# O( y W5 onetlogo自带的social science--traffic grid这一例子当中,8 O- P9 H, F4 J$ ?2 f9 T
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction0 i+ }! \5 Y" U* a
grid-y-inc ;; the amount of patches in between two roads in the y direction+ T- W1 t' n% k
acceleration ;; the constant that controls how much a car speeds up or slows down by if
1 j. h" w: I. N5 ^ ;; it is to accelerate or decelerate
/ B+ h, C6 [6 u2 F: z phase ;; keeps track of the phase& ]- |3 j; u% z7 H
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure7 U' R1 q- {; L" V
current-light ;; the currently selected light; w* V' W$ g+ y( [
: @- r! ?# ?7 a( R! ~' | ;; patch agentsets
6 _& q1 c) i( e intersections ;; agentset containing the patches that are intersections# [* G# `0 H( Z, A9 L
roads ;; agentset containing the patches that are roads! V4 e# P( S( j w+ B
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+ c8 B0 Z: o. H" y# a0 b3 {0 p; Gturtles-own, Y* A, @: Z" ^$ V2 v5 D
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* s1 a3 |8 E4 X, e- \ speed ;; the speed of the turtle
8 _8 D. u# p% X1 ^7 d a- P1 X up-car? ;; true if the turtle moves downwards and false if it moves to the right7 J' X4 @& x5 b7 ]4 ?. v$ |3 h
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 roads7 }: a1 W @& W$ }; w/ F4 P: D7 M" i
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
) e- h0 x$ @ n3 ^4 Q, b# b ;; false for a non-intersection patches.
$ O) E; P2 y! I1 V6 i$ ^* w- I. F my-row ;; the row of the intersection counting from the upper left corner of the
; B% U- ]3 T8 X- n$ M ;; world. -1 for non-intersection patches.. i. Z+ f0 u+ R
my-column ;; the column of the intersection counting from the upper left corner of the, `9 o/ n/ ?# ?. ?* N) J
;; world. -1 for non-intersection patches.3 N& L5 N: r# u. ?8 ?
my-phase ;; the phase for the intersection. -1 for non-intersection patches.+ g6 H1 Q! R5 p3 \, d- i* V% n# `
auto? ;; whether or not this intersection will switch automatically.
9 v6 \7 Q. {7 N, Q% W$ c9 ~ D ;; false for non-intersection patches.
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5 ^3 H- G- }, f' g. O( i% o;;;;;;;;;;;;;;;;;;;;;;' _) @+ c( y& M5 H1 A, Q
;; Setup Procedures ;;" ~" \9 ~, i2 B# e
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values., n. h R( ]' q
;; Create num-cars of turtles if there are enough road patches for one turtle to2 k( O; ]9 ^3 [6 e1 _
;; be created per road patch. Set up the plots.
/ M- h- g- A. A1 O6 O( j8 B3 hto setup
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* {3 j) e" D' D. _. {$ b setup-globals0 t' S# t5 q" w v% L) P
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;; First we ask the patches to draw themselves and set up a few variables m, S4 T, j+ [" V4 W3 S
setup-patches
+ }. P& E7 k% m ^5 T make-current one-of intersections
" \/ r4 Z6 M. G0 x2 ]) ]" n label-current
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set-default-shape turtles "car"& D9 Y/ C$ L; q. f5 A! |* d
5 I3 a8 p2 O; l$ s" J6 B% ` if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "% }- T: X# V0 m: D2 X. a- n7 f, l0 z
"road. Either increase the amount of roads "
* a8 I$ L0 J) I. ~3 C "by increasing the GRID-SIZE-X or "7 K1 v# S! C9 Z9 a4 C6 L# F& ]
"GRID-SIZE-Y sliders, or decrease the "# C, C1 q% R8 n1 r( ?
"number of cars by lowering the NUMBER slider.\n"
' Q1 T0 Y/ {6 S) L "The setup has stopped.")- C- B: T& a$ ?' C' j
stop
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! |8 h7 I# C7 N' Z( v1 [& X/ n ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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setup-cars0 o& P4 [7 d5 c Q, k* I7 M# X
set-car-color. a* X+ ]" `: {5 @& k9 c+ I0 e
record-data
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, P ?6 R& }4 E5 y! z% r ;; give the turtles an initial speed. z( |1 _$ v9 @& \' c# P# [. t9 L+ y
ask turtles [ set-car-speed ]! q$ r+ w7 Q4 B3 I
6 Z+ E# ?4 C% m0 i# @4 ? K2 B reset-ticks1 a+ ]& H4 e g/ h" |
end
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2 }' k# a9 t" a# |;; Initialize the global variables to appropriate values
# }2 ?/ Q, D8 A2 z( U2 xto setup-globals
' U" Q$ }1 x9 u/ b$ f set current-light nobody ;; just for now, since there are no lights yet" P0 ~ K' ]3 U% x, z+ \( b X
set phase 0& h3 c0 c+ @( E' E- c1 g( N
set num-cars-stopped 0
5 V* L+ M" `' \4 s" G' w set grid-x-inc world-width / grid-size-x: L! y5 h+ E/ q7 ^9 @% K
set grid-y-inc world-height / grid-size-y
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+ J$ m, ~$ Q/ d: D0 C" p0 R% A- } ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary2 W7 f7 j) X( ^( Z+ f- ?
set acceleration 0.099
' {: [, ^5 A, J nend
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7 y6 G' [/ D4 N% _, j: d6 M;; Make the patches have appropriate colors, set up the roads and intersections agentsets,9 o; w7 A5 [- {$ N1 y, ]2 Z
;; and initialize the traffic lights to one setting
# X4 s' ^$ G7 Zto setup-patches; H: p& l( \) h) N8 a7 N+ H: t# g3 F
;; initialize the patch-owned variables and color the patches to a base-color% Q0 H3 R# \7 c- X7 b
ask patches+ F; X6 w$ M* f. Y; ?
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! H% U5 A8 m I set intersection? false6 k6 l; t' `5 F5 t3 t9 @0 Q
set auto? false4 |) b; X ]* v; h2 K7 L
set green-light-up? true
2 W$ C0 ?3 y/ ~, D1 \$ |) L$ ] set my-row -1" w/ V {/ `/ }6 ?5 w3 C
set my-column -1: L j+ f. l6 @! l1 g0 R! J
set my-phase -1& @- D; t1 i; s7 \
set pcolor brown + 3 J4 [. E1 _; U8 W: b; r
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;; initialize the global variables that hold patch agentsets' n7 v, h0 b, t& D, ?
set roads patches with
9 n9 {( e# L% I/ p# h7 L/ d H [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ {; r% ?& M. k# M2 A) z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- J4 S* |. }. M( @8 Z
set intersections roads with
5 h, J* E2 w' f8 Q" P D) L9 J [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 @' \! Z, k. l# @: ~! d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% E4 U5 m3 h6 n
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ask roads [ set pcolor white ]
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5 S( t/ j: e5 V7 x6 q# h# Lend
; n& v. y2 L2 e# p. ]5 t0 [其中定义道路的句子,如下所示,是什么意思啊?
0 d4 J/ A- W3 A* s" j set roads patches with
3 O) Q( X$ f+ E$ T( U! M0 x% _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% w' C8 a g& T9 a* x% Z6 N1 L (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 _# ~! [& o3 s% t9 S% _' |! 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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