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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。
/ {8 g9 E. J1 A7 e3 E/ Nnetlogo自带的social science--traffic grid这一例子当中,* [! d. F/ R$ o* }$ [
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
( x) j/ P; B" K$ r9 E. s grid-y-inc ;; the amount of patches in between two roads in the y direction
' K- o; b; c. e" n( M# b% L, t acceleration ;; the constant that controls how much a car speeds up or slows down by if2 c# `7 m' ~+ O1 ]4 n% u
;; it is to accelerate or decelerate/ j; t( @- u- P+ s+ }. W* F. J2 n4 c
phase ;; keeps track of the phase
( z+ o i/ o3 }: J0 V% x' M" H2 N3 J num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
1 b6 f: c$ J1 Q* v5 T0 N3 v- S9 M current-light ;; the currently selected light& J$ s; {6 U" C" t2 K; a) m
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;; patch agentsets5 G: n5 u; p% j) V
intersections ;; agentset containing the patches that are intersections
$ E: k# G1 y, K& P roads ;; agentset containing the patches that are roads
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. s, P# H% y0 fturtles-own
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speed ;; the speed of the turtle7 q/ Z% H: m/ X
up-car? ;; true if the turtle moves downwards and false if it moves to the right" m; Z8 k0 W4 Q+ r' k
wait-time ;; the amount of time since the last time a turtle has moved2 u# u0 p& B5 y- _
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patches-own% H7 W) V/ _, W+ [& l+ Z
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( a$ e( R$ E, m intersection? ;; true if the patch is at the intersection of two roads% \( f K+ X1 M; Q: K5 ?
green-light-up? ;; true if the green light is above the intersection. otherwise, false.# Q }. \0 ~# E$ f8 t4 V* _" j! Z
;; false for a non-intersection patches.
0 R1 f4 G3 Z1 d0 {! R% H$ u my-row ;; the row of the intersection counting from the upper left corner of the1 K' S: Y0 G' i# J# P
;; world. -1 for non-intersection patches.
" ?% @- c+ A- i1 C& C! h my-column ;; the column of the intersection counting from the upper left corner of the
/ I5 M' o& K% I8 k ;; world. -1 for non-intersection patches.
6 X. Z+ w4 \ _3 W' C7 b my-phase ;; the phase for the intersection. -1 for non-intersection patches.( {: H* u$ H% `" a* @) v
auto? ;; whether or not this intersection will switch automatically.7 a) A j& A) v* q8 }& @* c% d
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;. _: ~/ U* b1 I, ^
;; Setup Procedures ;;
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! Y( z/ g% a* A, g/ h0 E;; Initialize the display by giving the global and patch variables initial values.
2 S0 O0 b! N1 Q8 J6 r; \: @ R;; Create num-cars of turtles if there are enough road patches for one turtle to7 E6 I; H& c% l# [ C' R
;; be created per road patch. Set up the plots.# U0 h6 Q1 F; x3 j) {& }
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
7 r6 U9 a! u2 B, b) W setup-patches
3 b: e a3 b9 O5 i# @ make-current one-of intersections" w/ n( C% I2 V/ C- k+ V% Q
label-current
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set-default-shape turtles "car"
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+ V+ B* k" `+ _8 Z& f$ ? if (num-cars > count roads)
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% L" d A/ g& \, I+ U user-message (word "There are too many cars for the amount of ", M6 X; {6 j, G' N% R' G: U% b
"road. Either increase the amount of roads "
2 _1 c# M3 V# p; r. Z* a) T "by increasing the GRID-SIZE-X or "
* [, C' x4 a7 W/ t% o "GRID-SIZE-Y sliders, or decrease the "
1 }" v2 B* d) R0 M1 B6 ], n: [% } "number of cars by lowering the NUMBER slider.\n"
5 J. o, R: n$ X "The setup has stopped.")5 s, x& D8 F3 M' `; d/ L
stop6 i2 |6 b4 \8 X9 r9 k. n' S% y
]
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+ a- ?$ G& B/ L9 Y0 K0 l e) s ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color8 H6 [3 Y( h( ^
crt num-cars' t! _; B6 _3 v" N; y( U3 U
[
5 n" b E2 m5 K; x0 P! W# R" A setup-cars. l$ K0 G/ ~1 i0 g+ q" r8 I0 ^( c
set-car-color* s1 ?- T2 t) V! W/ w
record-data. T P3 [# Y1 l
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- r. O$ T! R+ F ;; give the turtles an initial speed
+ ^& A4 s7 ~ E' v* Y+ e$ \5 C ask turtles [ set-car-speed ]
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' K0 ^/ g' _7 r* U reset-ticks
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;; Initialize the global variables to appropriate values% a( N! o, j( c) U% \/ o# }# _
to setup-globals3 e! U/ I" A( u2 F
set current-light nobody ;; just for now, since there are no lights yet/ P3 s" [3 F- n
set phase 0
9 R! [0 L: n. f) g1 u set num-cars-stopped 0
0 v5 h3 d0 n2 X, q; M2 Z" Z- V set grid-x-inc world-width / grid-size-x
8 ]) q1 r0 F# @+ s& | set grid-y-inc world-height / grid-size-y3 f! y. N' E/ a7 u
8 C2 B; l& K3 X5 x6 |3 V ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary0 I9 J0 y4 ~9 E3 S9 k: d, N
set acceleration 0.0995 x5 C- Y2 o3 W" u' Z; o @- ~
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,+ r6 V/ `% o; P' H) X; b
;; and initialize the traffic lights to one setting
" O' U8 O$ L7 Q7 _ V9 Xto setup-patches1 A3 W) r4 P# j- z* j
;; initialize the patch-owned variables and color the patches to a base-color
6 u/ Y; {$ v: ]& Q6 O1 W! t+ _1 N( l ask patches
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* J- d" ^/ x$ g2 d set intersection? false7 o6 X; F E& _& q9 T" z
set auto? false4 u% S: d1 Z |$ y% S; `
set green-light-up? true
+ B9 h' Q' h3 i1 S+ Z" J6 ? set my-row -1
9 s2 ?: I5 P. F set my-column -1
) C$ |* \( C- ^8 M6 x set my-phase -1
2 m+ m! j1 Y2 s1 v! d* k! } set pcolor brown + 3 ]" J6 J, ~$ N1 x
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" k$ T! r$ ?1 H+ {9 | ;; initialize the global variables that hold patch agentsets/ I% |( N# ?& L/ B2 `6 `" s3 R
set roads patches with& l; B2 A) {$ Z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, {8 W! |. z2 k; s4 J# v* O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' u9 T: }' d, O, z# k6 s set intersections roads with! X" A* W; H7 c0 C9 I$ d9 d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and* I! Q& M8 T5 D$ H
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]! d B: N& G! H. z( H9 k0 w
setup-intersections4 D3 T+ y4 i6 f. V9 y' j8 S
end# Q6 l3 o: I$ j; r* Q* \
其中定义道路的句子,如下所示,是什么意思啊?
h2 ?; J j+ L) [: m set roads patches with3 a7 F5 i& h: i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- q' W: r% t4 Z7 ^6 a# e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 S1 ?" R0 x0 E% k3 J5 R! X% d5 i3 [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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