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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。
2 v( W" a8 }/ v( q5 {# Nnetlogo自带的social science--traffic grid这一例子当中,
) Q1 `) M/ ^! {' J7 f5 h9 ]# ?globals$ u! B6 Q! Y4 T2 g. _
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, F7 K2 p2 a' `% p ?) x, i grid-x-inc ;; the amount of patches in between two roads in the x direction. |, ~% |3 i$ T
grid-y-inc ;; the amount of patches in between two roads in the y direction' G- A) `8 l) t" Y$ A* K H `5 M9 `
acceleration ;; the constant that controls how much a car speeds up or slows down by if
" o7 I! B2 D( b( z" @ ;; it is to accelerate or decelerate. h, i1 M8 m+ T \
phase ;; keeps track of the phase' q6 Z; @& I3 Q5 n4 L+ N3 z
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
4 i+ {' s; F1 B. h( j# t! h current-light ;; the currently selected light
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- i% x4 Q9 ~- \. j ;; patch agentsets
9 B( ]$ x+ H( O% m7 Z- p intersections ;; agentset containing the patches that are intersections
: }( ~8 k6 T8 a6 ~- q roads ;; agentset containing the patches that are roads
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turtles-own3 b1 U. ]# S4 H9 M/ _! l* q, ^8 w" I
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speed ;; the speed of the turtle9 J4 {- e2 r$ J0 M0 x$ v( a5 R7 Q0 T
up-car? ;; true if the turtle moves downwards and false if it moves to the right
& c( ]3 r; F2 Q6 I) @ wait-time ;; the amount of time since the last time a turtle has moved: H. x4 d/ R/ S9 G6 ?' ]( @0 @
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
4 e* V' T: z% K: d6 q green-light-up? ;; true if the green light is above the intersection. otherwise, false.
( X, \/ \% O8 D; n$ }3 ^, ?, o ;; false for a non-intersection patches.
: F& \/ u4 e8 a9 \0 @ my-row ;; the row of the intersection counting from the upper left corner of the( B K d7 d4 j4 G
;; world. -1 for non-intersection patches.
9 Z) P* `" n, ^) m; o% r+ f9 E/ W my-column ;; the column of the intersection counting from the upper left corner of the
4 x8 S1 D/ u' w# _# ^ ;; world. -1 for non-intersection patches.
/ k0 R' y+ |; S) ~ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
A) V8 n# C& M$ [ auto? ;; whether or not this intersection will switch automatically." c: B1 B7 F& C: S8 E+ G
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;1 H+ _+ D8 K a3 ~* W: v
;; Setup Procedures ;;
4 n3 A# k$ M% `/ }- x;;;;;;;;;;;;;;;;;;;;;;
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: z8 k9 f2 K* M: R;; Initialize the display by giving the global and patch variables initial values.
! ^1 L4 s) B' D# w% C( u$ p4 @;; Create num-cars of turtles if there are enough road patches for one turtle to' G, _- N3 a5 n' k' `; j. I
;; be created per road patch. Set up the plots.# H" [4 y- E, V `' d
to setup
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7 S. z: I Z1 p) _7 w setup-globals
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" l( ?1 [. \ Y h# Z ;; First we ask the patches to draw themselves and set up a few variables% V- X* Z$ I6 u. N9 v6 P- ^' Q# ]
setup-patches
8 a5 L! n; `% D) X make-current one-of intersections
) y# ] U' L' S! w label-current9 H+ Y- E! { Q+ U
; r- z3 N; A& x set-default-shape turtles "car"( |/ g+ | X1 A$ h2 L2 U
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if (num-cars > count roads)5 h2 e! |' r) G" ~4 j* m2 }7 I7 w
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/ K- g, [1 B3 a+ o1 s user-message (word "There are too many cars for the amount of "2 C. |8 J, q0 {; p: p- Z y5 _
"road. Either increase the amount of roads "- }9 x! Q% f2 W0 e
"by increasing the GRID-SIZE-X or "
! W5 T; O; j" e9 z) J* r% ]; W6 ? "GRID-SIZE-Y sliders, or decrease the "
% u/ C4 V, m* A! Y' v "number of cars by lowering the NUMBER slider.\n"6 S/ h9 Y5 h6 N, W* b% B
"The setup has stopped.")
7 S! M1 H; ~; O) O* q1 ~! `& u% O stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
Z! k% L; q7 [9 a- u crt num-cars
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6 F/ o* V9 r; W5 B/ {. Z4 p setup-cars
. y E; Y& p& i& u set-car-color
/ a. W5 K* W$ V, s3 l record-data
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;; give the turtles an initial speed$ U' v4 {+ d. O
ask turtles [ set-car-speed ]9 X& o2 \# {! D$ s1 S" [) X
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reset-ticks
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* x! d9 U/ S5 g) v1 |;; Initialize the global variables to appropriate values
: @- V5 w( ~) N: Q2 Nto setup-globals1 M& ?2 h% u5 r% `
set current-light nobody ;; just for now, since there are no lights yet
0 V# M, [4 {# v) n: n4 o/ }% F set phase 0
1 F0 z1 ^2 H0 d8 j0 t: y set num-cars-stopped 0" D& Z, m& V% l* `, J
set grid-x-inc world-width / grid-size-x/ W: d$ I6 c r- @* u
set grid-y-inc world-height / grid-size-y0 ^; {/ M. k, ?# i
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
$ p1 x0 y: k& \4 T set acceleration 0.099
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9 @, W a9 s4 h# T$ h- `;; Make the patches have appropriate colors, set up the roads and intersections agentsets,& ~, W0 C" N) W$ i
;; and initialize the traffic lights to one setting
/ b0 y4 j- A% W; u( g* Z6 d" Tto setup-patches- o7 @" U/ `8 S, I9 o+ r
;; initialize the patch-owned variables and color the patches to a base-color' }7 N9 d. D4 `! z5 s/ l
ask patches) @& ^, A" M- b, m1 o& g( F, ^
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set intersection? false
$ H$ e, V: j% p( v w set auto? false
# L4 y4 w7 y4 F4 x0 J set green-light-up? true' u/ W! ]) d- E. _! N8 G- E
set my-row -1
3 Y3 E& s6 ^# h# H V; D set my-column -1
+ b3 x7 S% O+ a- {. V: ^ set my-phase -11 ]+ {4 r. r6 z0 |2 E
set pcolor brown + 3/ I. A3 Z; f8 }7 d* ?/ V( L0 Z
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;; initialize the global variables that hold patch agentsets( j5 o* R1 g6 U: M& M. o: I
set roads patches with
9 ~* E) Z& D3 V' x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& i! @, ?9 v3 p$ U' t- o (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! v9 S2 G% z% ~1 i$ E set intersections roads with9 V' ]! Y |% q8 z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and) [, r) x" j# N; N; ~; t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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7 _4 a* V9 r! {4 K ask roads [ set pcolor white ]$ |5 I) ?" A6 W% n" F1 F6 W9 y
setup-intersections
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" T; l7 C# s c' K+ Y其中定义道路的句子,如下所示,是什么意思啊?
1 |# `2 z, Y) k set roads patches with
$ V0 a( b$ O1 s [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, w+ C, b9 q' [& {7 \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' |: h7 c1 X/ r0 U* c
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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