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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。
9 x5 L7 ^/ Q1 O- P" nnetlogo自带的social science--traffic grid这一例子当中,
! U) b6 C1 B8 S# `2 r1 `: g) Uglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction1 J. c; N" P% y" ]2 h) S
grid-y-inc ;; the amount of patches in between two roads in the y direction
2 N5 d0 c& o- F acceleration ;; the constant that controls how much a car speeds up or slows down by if
: X; `5 f5 Y& ~4 l( s ;; it is to accelerate or decelerate' w* V1 i2 J9 ]
phase ;; keeps track of the phase
- v6 {* `* ^( }+ @ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure* [! d0 k' a7 d$ Z
current-light ;; the currently selected light5 f8 R8 i h4 j; h
* }% B* f( e- v* K. G' c ;; patch agentsets
7 `* p6 K1 |- N: J6 `( c J intersections ;; agentset containing the patches that are intersections
! M+ M: k1 R3 { roads ;; agentset containing the patches that are roads9 I' G6 D h# g9 |. c) I
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turtles-own
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# t' M2 x4 t" j8 B- P5 u$ O; K speed ;; the speed of the turtle) ^3 u* O5 `7 W
up-car? ;; true if the turtle moves downwards and false if it moves to the right" N: }' y' Y: R; e5 Z6 |
wait-time ;; the amount of time since the last time a turtle has moved
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( q6 Z N) H. Xpatches-own$ r: f+ m: X) d2 a9 g# D6 i3 h2 B
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intersection? ;; true if the patch is at the intersection of two roads
! {9 Y; W4 [2 ]' B green-light-up? ;; true if the green light is above the intersection. otherwise, false.: y' r0 b) w" A c# U8 ^
;; false for a non-intersection patches.0 t8 M- L2 d# r3 k
my-row ;; the row of the intersection counting from the upper left corner of the9 R c5 q7 ]0 X F2 x
;; world. -1 for non-intersection patches.
" [) U6 U# ]. X+ m my-column ;; the column of the intersection counting from the upper left corner of the
9 M2 w. u) T# j7 p+ k ;; world. -1 for non-intersection patches.$ K j5 J- v* f9 m2 T" f
my-phase ;; the phase for the intersection. -1 for non-intersection patches.% A6 f. O$ C# g+ O& j3 \, K
auto? ;; whether or not this intersection will switch automatically." q7 _# b9 z* A! a
;; false for non-intersection patches.
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% x6 Y- |* `/ `9 W$ I- |. k ]
: j& B* w9 E8 M" t;;;;;;;;;;;;;;;;;;;;;;) l% H$ t7 E9 r) W7 r4 \ N
;; Setup Procedures ;;/ M: w" q9 }" l# ]+ x% s; d
;;;;;;;;;;;;;;;;;;;;;;7 x O2 R2 m+ {: e v
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;; Initialize the display by giving the global and patch variables initial values.7 G: X5 c4 \2 \: g' n
;; Create num-cars of turtles if there are enough road patches for one turtle to
+ r! g1 `, L; i* O$ e;; be created per road patch. Set up the plots." P' m6 z" C1 \& K' A _
to setup7 x* @" v1 x. U( Q+ p. I
ca
' Q( H$ z% n; ~ setup-globals' L. n9 D2 n6 X7 J( c
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;; First we ask the patches to draw themselves and set up a few variables
6 d3 f# q: ?6 z setup-patches0 p+ { j% j, D) h# C) z0 U
make-current one-of intersections
- W+ ?3 R/ c6 t2 ]4 g% K+ p label-current
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; `6 X0 z& n$ o9 h% G: ~ set-default-shape turtles "car"" R' \ m W6 a4 Q3 h1 L9 Z% j
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if (num-cars > count roads); T4 D0 H) d1 }; h8 w. B
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user-message (word "There are too many cars for the amount of "3 b* q6 F, t+ }% d( l
"road. Either increase the amount of roads "
. `: ^" a# q l6 a% C "by increasing the GRID-SIZE-X or "% f" C; G. H! {& j
"GRID-SIZE-Y sliders, or decrease the "+ O5 V" X( B1 F) b- m- @/ z
"number of cars by lowering the NUMBER slider.\n"
/ `+ g! c# _3 M+ b2 [: p2 j1 t* _, W "The setup has stopped.")
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$ D4 D, j: b7 ` ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color; q8 l! V( f) @
crt num-cars( u% X* Q3 Y# |3 P# M$ u, L
[
4 {# U8 T/ L, l3 v d setup-cars+ j# R9 G% f* J$ {% j
set-car-color
, M& G( X/ W C+ I$ P. }. t2 ^ record-data
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;; give the turtles an initial speed/ Y2 o& E4 X4 q2 U6 \+ l: u( r- r0 }
ask turtles [ set-car-speed ]
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reset-ticks- T7 R- [6 |! d2 D
end
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2 E" K4 m, Z% v- p' f8 ^;; Initialize the global variables to appropriate values
! A" X! t. a, ^( g! Sto setup-globals
$ o, |: l" N; b! \0 ~, T* @ set current-light nobody ;; just for now, since there are no lights yet6 s3 g2 G/ S2 _6 c* N0 H( O
set phase 0
$ R) B. i8 V' ~7 r1 N H1 e set num-cars-stopped 0* z7 c& T' q' a) o: Y% ?; |0 I
set grid-x-inc world-width / grid-size-x
1 m% V1 n+ [8 I$ G set grid-y-inc world-height / grid-size-y, I. {/ l" e) N4 z
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: C! |9 Z( Y3 {! A/ \
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,3 o+ k$ B: s) q4 _/ p
;; and initialize the traffic lights to one setting
2 l/ P7 }: b+ k5 ?& wto setup-patches
; l3 T$ {2 x. S7 q( ^ ;; initialize the patch-owned variables and color the patches to a base-color
& k) T: K/ z% \ ask patches y/ k5 z$ q9 W* {+ `
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, y# U9 [ ^+ O0 |0 z set intersection? false; e, ^, g% z! h6 c
set auto? false8 |1 w. d# F7 ]# k4 Q
set green-light-up? true
) O& v7 }: a! D& T set my-row -1 w6 s2 ^% L1 i- y2 b
set my-column -1! K- Q: r) F4 R9 X
set my-phase -18 G- v/ U2 p2 q4 `
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets; Q2 ~9 z5 r2 x# Y- F
set roads patches with
# L+ j7 J3 b' k- h$ H: ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
' X' `+ x/ e1 Q& | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 J. ^$ O s9 _' y6 `) ^
set intersections roads with0 W5 ?( R: C E/ I6 c7 v, ~3 |/ }
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, f8 q9 ]& Q# n# o/ {) v (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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& a7 ~5 a0 ?: ~' i, K6 l' F& o ask roads [ set pcolor white ]. A- y/ ^: t0 E% [+ Y
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?5 h, x# x1 `$ Y; |: g. d3 h, b& d# R
set roads patches with- \3 e0 y- Q# S. X4 L9 c5 X# ^* s
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
5 l! L: q7 \8 ?2 z) H5 [& D- I (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 o( f/ a& U, T6 p' ^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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