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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。5 @, I1 x, R& `) R' l% @: h4 c
netlogo自带的social science--traffic grid这一例子当中,
, u! @5 ~- {) Z: D+ h }globals! y$ g6 A( [9 u( v% Q& I6 H
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. s1 s$ H! A6 M& u% K C grid-x-inc ;; the amount of patches in between two roads in the x direction
- l8 f) a; v* W ~ grid-y-inc ;; the amount of patches in between two roads in the y direction# d8 ] L6 p+ Y. c" J
acceleration ;; the constant that controls how much a car speeds up or slows down by if
2 K5 q3 y' i9 H* x; @7 w" U2 B3 U ;; it is to accelerate or decelerate/ N; z7 o& K, c/ r, O, G3 `4 Z
phase ;; keeps track of the phase; |* F/ }6 ~: b8 [8 a
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ h* P% k: n6 r3 |
current-light ;; the currently selected light
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;; patch agentsets D9 {9 F& S2 e- X
intersections ;; agentset containing the patches that are intersections6 v1 @ q) \5 v3 k4 E
roads ;; agentset containing the patches that are roads+ ` `8 x f. j' K, k7 C+ S
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turtles-own
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speed ;; the speed of the turtle' G0 J# ]4 }2 a7 l4 c! ~2 _
up-car? ;; true if the turtle moves downwards and false if it moves to the right# k; |4 I" {; U4 }
wait-time ;; the amount of time since the last time a turtle has moved
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: {/ h; F) G6 ?patches-own7 m: w7 O- l& q, t1 @ S3 q) B/ k
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intersection? ;; true if the patch is at the intersection of two roads3 _& x7 O6 g' L) W3 q9 m l
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
2 }0 Y; t+ Q3 h( D( M- a ;; false for a non-intersection patches.; {5 Z2 i/ @7 w7 g" A
my-row ;; the row of the intersection counting from the upper left corner of the
+ D& \! i8 s5 Z ;; world. -1 for non-intersection patches.& g! g# M/ x. t' I0 i+ d0 U
my-column ;; the column of the intersection counting from the upper left corner of the
' ^1 D; J3 \2 I/ A ;; world. -1 for non-intersection patches.
/ k X& h. h5 [, s my-phase ;; the phase for the intersection. -1 for non-intersection patches.
& x& ~+ F `$ `, l/ j. p5 y auto? ;; whether or not this intersection will switch automatically.
, C: j! y J& H9 @3 w; ^# l ;; false for non-intersection patches.% T# d: [- Q0 g% R; q! p
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3 s( Q5 X0 _7 z w! Y" R;;;;;;;;;;;;;;;;;;;;;;" G) O& W6 E1 S* }2 J( G0 X: [* q
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values." ?; e5 r9 l% W' V& _! w4 G6 c
;; Create num-cars of turtles if there are enough road patches for one turtle to
4 Q, `! z$ h _;; be created per road patch. Set up the plots.
8 m$ C7 ]( H. A" o% D/ tto setup
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setup-globals2 _4 }9 R- U- ]- n8 ]' m! k9 `
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;; First we ask the patches to draw themselves and set up a few variables/ l5 s8 E4 z: j) y& q+ M
setup-patches3 Z1 f9 P- q# q2 X
make-current one-of intersections
1 o0 O7 x& o0 Z# U1 B, H- G+ w label-current
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set-default-shape turtles "car"
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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 "- H- Q+ m1 n7 b
"road. Either increase the amount of roads "
) K5 H2 ]# O c: F "by increasing the GRID-SIZE-X or "
# J) W& Y. n1 w2 { a "GRID-SIZE-Y sliders, or decrease the "$ a* C1 m$ g" j* `( X
"number of cars by lowering the NUMBER slider.\n"# @, @& \" P; b z g2 c5 X
"The setup has stopped.")0 Y' O% P# G* L3 L
stop$ J2 M" ]9 u8 X; D1 D
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 l# Z" x$ d& h! D/ x, ^ crt num-cars
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* T7 v$ i- g& ^ setup-cars. o) f( W- L( u+ V
set-car-color' Y; w/ l4 d- {4 Y3 u/ m
record-data- ?5 b2 k& g* c( n$ d
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; ?5 o, ]6 }3 @) z ;; give the turtles an initial speed
$ u2 Y; }. M: `" j ask turtles [ set-car-speed ]
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( Q8 j- Q# x% g. Y0 D reset-ticks0 }; _( W# q) X: u1 `2 ~4 Z
end" ?9 ~) B5 k; K+ _3 t7 `) T" g3 x
3 _' B$ K0 {- b3 [" C9 `/ e. C;; Initialize the global variables to appropriate values
; k. O" Q$ `2 Mto setup-globals' r7 K0 l. a1 e% o* r5 G* w5 {
set current-light nobody ;; just for now, since there are no lights yet
& G; I# p: \2 u/ W: t' }$ f set phase 0" T; q' P' H% y! J# V
set num-cars-stopped 0
) ]) l& O7 E3 V) R1 q) Y set grid-x-inc world-width / grid-size-x
9 h. q/ {: }8 T: i- a; A! A7 Y l- z set grid-y-inc world-height / grid-size-y! F& F1 `3 C& O
. E4 y1 E, _5 o ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary7 W" B+ S& x6 h" [5 f) I7 F, R
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) _4 q* Z! J! \: x4 {+ i
;; and initialize the traffic lights to one setting4 i$ Y' Y# x# R1 F; g) e9 ?
to setup-patches
6 w, ]/ _6 T& ?4 R# s* j ;; initialize the patch-owned variables and color the patches to a base-color
$ z: F2 _7 C! @' c ask patches
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set intersection? false6 k% G6 c0 V* c: z7 v7 |0 ]
set auto? false
; B: m: n# b4 S; t& O% a" |7 t; w set green-light-up? true+ ~/ E3 {7 z9 h, N! I p
set my-row -1: {6 a: e$ i$ G
set my-column -1
% @" F+ [. M, } k2 _* }1 k# a0 H set my-phase -1
: I, e) t2 B5 u& B. w( O set pcolor brown + 3( T A* w3 F, y$ O5 W
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3 e" x/ N! B0 p# U6 @6 ^ ;; initialize the global variables that hold patch agentsets, _$ v" K: O- \, u, w
set roads patches with, Y( I" S0 u" V
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 X' r' `' m4 u- `2 b8 f- s
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
p6 |3 u# h# X" |, i set intersections roads with! B$ W7 D9 \- O6 B+ q( m3 X
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" F6 \" q4 C: e4 w4 b (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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5 G$ H0 @' @! A ask roads [ set pcolor white ]) H M8 x/ I1 h
setup-intersections
5 b2 X4 n8 ?# }4 Z9 b+ s* eend
4 J5 o; d, }1 x( t, s9 Y- j) e其中定义道路的句子,如下所示,是什么意思啊?! ^- P3 O0 q" `! z( b
set roads patches with2 k* v$ C5 }* N. { L' A+ f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 d: D8 z' j! f! Y
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# M1 b0 o% y1 n: [3 J8 x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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