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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 B1 W; N* k1 ]; @% u" Y+ Lnetlogo自带的social science--traffic grid这一例子当中,
3 S" R, p( s v* t, L3 |globals) V) {2 y4 s, R0 ] O
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grid-x-inc ;; the amount of patches in between two roads in the x direction
! S) F) ?7 C- j$ z grid-y-inc ;; the amount of patches in between two roads in the y direction1 C% t# R4 L! U( {' Y/ S# K
acceleration ;; the constant that controls how much a car speeds up or slows down by if2 C/ ]& X- e9 y; q# C8 n+ W8 G
;; it is to accelerate or decelerate" r- Y f# N+ r# Y) v5 Z# m2 r
phase ;; keeps track of the phase
& {- g$ U( p9 w num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure) I# o6 M6 t8 }0 a/ v) h/ \! B
current-light ;; the currently selected light
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;; patch agentsets
: H7 r( V. M0 G8 e) Y' F/ i intersections ;; agentset containing the patches that are intersections
Y$ d! Y0 V7 x" {* U8 F roads ;; agentset containing the patches that are roads# c- u$ x6 o6 I; t3 R
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turtles-own
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: y' @0 H: I) j; f: U! ~+ ] speed ;; the speed of the turtle
$ U" a+ o- n w% M up-car? ;; true if the turtle moves downwards and false if it moves to the right1 i3 k" B. }7 m6 n- m+ P
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own% Z/ K3 W: c0 p
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intersection? ;; true if the patch is at the intersection of two roads
. O, o" F' ?4 R green-light-up? ;; true if the green light is above the intersection. otherwise, false.2 w2 n" d3 P9 h e s' S
;; false for a non-intersection patches.
7 y4 x; v0 c! r* | my-row ;; the row of the intersection counting from the upper left corner of the
+ T& ^/ }2 l( `- A5 O/ G ;; world. -1 for non-intersection patches.
7 @+ w) e6 a9 v! _ my-column ;; the column of the intersection counting from the upper left corner of the
: J! x) @/ a& G7 r" H ;; world. -1 for non-intersection patches.' L% D& O8 I, U
my-phase ;; the phase for the intersection. -1 for non-intersection patches.1 M2 o: o9 l. l% P6 F0 K
auto? ;; whether or not this intersection will switch automatically.8 ^& X+ W2 P8 d
;; false for non-intersection patches.3 ]8 T4 d' v" M7 S
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8 B4 U% `, k. S) I( m;;;;;;;;;;;;;;;;;;;;;;
2 J/ v$ `+ Q; H( X;; Setup Procedures ;;# W4 S/ s! _2 O/ V9 C
;;;;;;;;;;;;;;;;;;;;;;7 N( C1 {# b9 i1 k' ?) o
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;; Initialize the display by giving the global and patch variables initial values.
& d# }# M! ?* l; B, E @;; Create num-cars of turtles if there are enough road patches for one turtle to
7 S9 I. ~- A4 ~4 W7 R' ^+ \;; be created per road patch. Set up the plots.
6 Q; h' ]% h. p0 @to setup/ T/ ^' Y( ~& k3 \! a5 i, o
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables& _" B* g; `! N! }0 [
setup-patches1 L, K, ?# _8 P
make-current one-of intersections
$ C$ X9 k9 B9 O, m 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 "( W. p( x+ {3 p, O0 ~
"road. Either increase the amount of roads ". m: }. E2 L7 ~+ z& w( j$ ^- j1 x
"by increasing the GRID-SIZE-X or "+ o; A% e$ Q2 H( k7 x
"GRID-SIZE-Y sliders, or decrease the "# A. E& l# r) k; O
"number of cars by lowering the NUMBER slider.\n"
; M7 F4 h# L x" i7 o "The setup has stopped.")" ]( r# I5 J# u) F
stop
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* Y8 [2 e6 e9 ~7 j" Y9 E8 M: z ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color8 ^) {7 ]2 o; O* u* w: i! x
crt num-cars
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setup-cars7 ~2 ]5 e% Z* ~$ R: Y# c
set-car-color
8 W/ x4 S3 f8 A9 S4 \/ o record-data# R6 V& N Z3 q$ g1 |6 [
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) ^2 e4 J+ g3 X6 u6 q0 K$ _4 r ;; give the turtles an initial speed
0 u- [- f4 S7 O% w% e ask turtles [ set-car-speed ]$ U: A4 o3 m; l* }8 C
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reset-ticks
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;; Initialize the global variables to appropriate values- Z. G8 R% u5 T6 h, {9 r0 H6 n
to setup-globals5 C9 x& \3 e9 o
set current-light nobody ;; just for now, since there are no lights yet
/ y1 R4 S. t/ p' E- I set phase 0
& o7 ]; [/ T. [0 I/ g j+ x set num-cars-stopped 0) b) L8 z$ H, W/ E" y# v/ K# P
set grid-x-inc world-width / grid-size-x ^8 t; S8 c a {0 X
set grid-y-inc world-height / grid-size-y
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2 v) G Q- a3 h$ W, W. a ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
" q" i8 a& I* Z set acceleration 0.099' m5 z, l$ U3 F4 G# G
end, j8 E4 T) F; _% X @2 S9 j
/ m# h' u. i7 q& ^8 @1 L;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
* n$ E, O/ N! [;; and initialize the traffic lights to one setting
6 k5 e* d# X; i6 P5 S( _4 p% }; Cto setup-patches
9 Z: k) [! d1 D; A ;; initialize the patch-owned variables and color the patches to a base-color, Q8 F* c' N3 u. g4 {
ask patches
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2 s2 b# w: z5 `: h2 A set intersection? false
7 Y6 ]) v' R9 _: n set auto? false
5 D- I- i- k) t set green-light-up? true4 D5 C. ~- f6 S5 k2 X9 w
set my-row -1
* |" r @' [, E' M' V set my-column -1
, V5 Z B% V/ j0 M9 X1 b% }/ ? set my-phase -1
! `$ Q+ p' {0 V$ c) s set pcolor brown + 3
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, i9 p7 L$ d- I. _, A i# | ;; initialize the global variables that hold patch agentsets
9 c+ O5 f' t: Y C: o set roads patches with+ ~" _# h) P& E8 d1 d6 l
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or( v: y) w3 M0 X. B$ m5 X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]* p9 G2 i. T# v: r: a) } R& O) c. \% ?
set intersections roads with. I1 J& G: V5 }; |
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, a1 J0 N! I. C4 x# E u3 m0 s (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end4 y: w, R. Z, N8 u
其中定义道路的句子,如下所示,是什么意思啊?# c( w$ E3 c0 r! U& J8 D- m; F
set roads patches with* K* z+ j9 r* x: b$ R
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 t& x4 y5 c/ Z1 j/ d" m; R (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# ?) F0 A* T5 @( 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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