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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。
$ e1 e) a% O* s5 I( Tnetlogo自带的social science--traffic grid这一例子当中,
& ?/ h# N, ]/ c9 Q g9 Cglobals5 \9 @# C+ x8 u) N/ W% U8 h) Y8 a* U
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grid-x-inc ;; the amount of patches in between two roads in the x direction
' L: ]% \7 b+ r) M4 J grid-y-inc ;; the amount of patches in between two roads in the y direction
: p( H0 a& y, M9 _ Z acceleration ;; the constant that controls how much a car speeds up or slows down by if
% @% z" q# B S, g) W- M6 I1 I ;; it is to accelerate or decelerate5 o: A' I: \7 A! ~, e. k+ G
phase ;; keeps track of the phase
: h4 s8 f. H2 K$ z num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
% u% c. a9 ?5 d! G* M5 d, \- U& j current-light ;; the currently selected light
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# U1 n. u# D& R4 d ;; patch agentsets
( L" m/ ]7 C8 J0 d intersections ;; agentset containing the patches that are intersections. D- }+ f1 \& j h- t
roads ;; agentset containing the patches that are roads
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6 q- x8 A4 z* S& o& j6 ^7 pturtles-own: O! s' J$ \% U3 d* {
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speed ;; the speed of the turtle6 \( p3 E3 H6 _2 H& C5 o. S$ e
up-car? ;; true if the turtle moves downwards and false if it moves to the right
, m' E1 C3 _ Q# k! K. ?1 N wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
1 t+ X% Q; D( ]3 K green-light-up? ;; true if the green light is above the intersection. otherwise, false.
& L- |" P3 U" b+ Y7 B* H ;; false for a non-intersection patches.' Q0 q& @" ?) L7 C5 D, @
my-row ;; the row of the intersection counting from the upper left corner of the
5 \" Q X) h' v( D3 y+ w ;; world. -1 for non-intersection patches.. z$ S1 U" p- X
my-column ;; the column of the intersection counting from the upper left corner of the
5 P! p: l, J& T0 B5 i ;; world. -1 for non-intersection patches./ e( X; Y. p9 j; a8 b' u
my-phase ;; the phase for the intersection. -1 for non-intersection patches.7 n& U2 r1 w* Z* ~; G6 M z) t
auto? ;; whether or not this intersection will switch automatically.- T! ^( o" S/ m- c8 @
;; false for non-intersection patches.9 E( d5 e$ T3 Y3 e
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;;;;;;;;;;;;;;;;;;;;;;
- K5 h6 t' Y/ j" d; |+ [;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.9 W0 S n" r; c$ ]* o) C
;; Create num-cars of turtles if there are enough road patches for one turtle to
( m! |# y0 C3 `/ ?' c8 q c# V$ l;; be created per road patch. Set up the plots.
; U2 Q9 g* [) M/ S, f. K! jto setup
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" n6 C) u) r3 v( R setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
& Z: @: U( m! T( c, s setup-patches
( t) [: u# x2 v' H4 u+ w3 O! V make-current one-of intersections
4 F9 \) @6 W3 }8 _! F% s1 }6 a label-current
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1 c1 \# v) U( w4 f) f" W set-default-shape turtles "car"
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5 M' c$ P' x! a" N B9 o X# R if (num-cars > count roads)- H/ G: \2 ^9 l( }. S+ b/ s2 p
[
- P' p- k$ Q$ p6 u; X& _ user-message (word "There are too many cars for the amount of "+ n, w P5 T8 E" v3 y4 K
"road. Either increase the amount of roads "8 A# L! M+ @+ O& F
"by increasing the GRID-SIZE-X or ") f/ Y- F* T4 G( e6 e/ l
"GRID-SIZE-Y sliders, or decrease the "9 Q) V" K" ~" g" U# _) I# X6 g! n
"number of cars by lowering the NUMBER slider.\n"
( O. ^) `+ z, E0 W6 ^ "The setup has stopped.")
# B9 n$ Y' ?5 L) L stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color. \: }: ]5 Y/ t; D# P
crt num-cars2 q/ c' J7 r. q( B+ m7 ]/ n
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setup-cars2 [$ q9 Y; G' \
set-car-color9 y3 Z* x- ]1 q" n5 x
record-data$ F! C3 r# b0 S4 i/ t
]
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;; give the turtles an initial speed
+ Y/ s' d, K+ c$ R* x8 X ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values
3 m' U1 t& ]) i* W( A, `: hto setup-globals
8 W3 [3 v/ x# [. l- J D1 q7 F set current-light nobody ;; just for now, since there are no lights yet
3 \4 c. u1 y# N1 I. p) q& N, | H set phase 0
9 ^) w& j: b, {/ ~; a, L# F6 p set num-cars-stopped 0) W4 h# D* H/ d' a B5 {- e
set grid-x-inc world-width / grid-size-x6 k5 S! o4 A3 s
set grid-y-inc world-height / grid-size-y
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, s" s9 [8 M7 I# c ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
5 S. D; ?- X! G8 H1 u7 p set acceleration 0.099. G' |( X o, j8 _4 d. [3 k: g2 L
end6 g+ z* m, t0 d; Q P
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,( M/ }* H# ~3 n3 p9 G- P
;; and initialize the traffic lights to one setting* o* C5 v) f4 L5 B' [; v! o$ ?
to setup-patches( p l) ^4 F4 Y
;; initialize the patch-owned variables and color the patches to a base-color
1 g2 |& N. z$ k& h# ~ ask patches L) F1 `% z6 r2 k' @+ x" ?' w6 X
[
" R9 S+ T' d, W# N# [& v set intersection? false1 a+ x% }0 A. ^' i' W8 b( _ f; ?
set auto? false* Y' L, q9 \" d5 N) N; Z
set green-light-up? true
8 O2 W5 N" H5 x set my-row -1* j$ j8 h) V. ~3 F* h F$ E
set my-column -1! q# `. u/ k5 l( [& S, w5 A
set my-phase -1" {, L( N+ y G
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets5 D; R/ [. F3 n, {- |& t" X# E
set roads patches with
6 c1 a3 G! r* i( ? [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 R6 T& {$ }: _1 I1 S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 E( @6 L' D+ G$ d0 |! k% L2 a7 S+ K4 K set intersections roads with2 t2 y* r X9 _# Y i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and) e, n; U v0 Y" [
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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: A7 j0 ^% v5 a5 V% s$ W ask roads [ set pcolor white ]+ r' E1 n3 k: w1 H) K
setup-intersections/ Y2 ^9 ~$ w1 ~2 s5 w- ?9 J7 E
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其中定义道路的句子,如下所示,是什么意思啊?: ~; ~) a) k, D& A
set roads patches with, O# w# D! a9 K, ?' Y3 f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% X& J$ ~8 t) n! r (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, @* q* J$ x5 l$ Z. u5 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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