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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。
# ]" S! o; P+ Q. z0 I! Q" T5 [netlogo自带的social science--traffic grid这一例子当中,4 l* u7 k. s3 k, b7 x
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction S9 {3 `/ D9 k
grid-y-inc ;; the amount of patches in between two roads in the y direction) f6 Y. K' N' D
acceleration ;; the constant that controls how much a car speeds up or slows down by if
8 r3 m3 C% L$ I7 m/ I) ? ;; it is to accelerate or decelerate
/ q8 |8 f* x4 G0 O H phase ;; keeps track of the phase- F$ P2 c& d# Y
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
5 w1 N+ H2 y' f( {: v current-light ;; the currently selected light
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3 f O7 f# m3 x, o2 S! k. \& s ;; patch agentsets
9 F4 O2 L! g4 r intersections ;; agentset containing the patches that are intersections6 y6 T6 _! W% i3 g8 l1 u' u- I! x0 J
roads ;; agentset containing the patches that are roads
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7 ?1 i: g. e1 K' p9 ~5 \turtles-own
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' O% E( S% c* C speed ;; the speed of the turtle' g- d& P, b+ g2 n
up-car? ;; true if the turtle moves downwards and false if it moves to the right% }; T- p6 R3 r
wait-time ;; the amount of time since the last time a turtle has moved
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- o! M0 a$ E& _8 S7 @patches-own
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intersection? ;; true if the patch is at the intersection of two roads
, e9 d: }: d& i# @ z4 o/ n8 z green-light-up? ;; true if the green light is above the intersection. otherwise, false.; W4 S- E. B: `( r
;; false for a non-intersection patches." {. ^: X5 A" D( i I
my-row ;; the row of the intersection counting from the upper left corner of the [; g7 ? x5 E0 u6 b7 J) U; t
;; world. -1 for non-intersection patches.6 }; O8 j' _; a5 K7 d' n( C
my-column ;; the column of the intersection counting from the upper left corner of the. S) }( C) ]9 h9 w' Q
;; world. -1 for non-intersection patches.* F7 f: s) Q2 M
my-phase ;; the phase for the intersection. -1 for non-intersection patches.- G) M* M* G- N, d
auto? ;; whether or not this intersection will switch automatically.5 O' \6 l6 g0 A% H8 n' `
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
4 \+ ]2 t# q% F* T$ B' t;; Setup Procedures ;;
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4 o7 Z/ c" R( L7 t$ U' P! ]$ L; Y;; Initialize the display by giving the global and patch variables initial values.9 [4 x' u% B7 `( c; [" C; t
;; Create num-cars of turtles if there are enough road patches for one turtle to
& l& [" U" [# B% d;; be created per road patch. Set up the plots.
5 c' A" I5 N I1 e! h4 nto setup
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setup-globals2 R0 z& t2 w" V8 x- Q
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;; First we ask the patches to draw themselves and set up a few variables
1 S' X7 j+ P: z+ S7 \ setup-patches: I1 N1 U- u' i# U. k) O1 Y
make-current one-of intersections5 Y& \1 D+ X/ R$ ^
label-current
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3 m" V! Q6 L& z2 e% r set-default-shape turtles "car"
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0 I: m% a) I' d$ O5 ]: B if (num-cars > count roads)5 O# N' p! A7 q5 _) @
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user-message (word "There are too many cars for the amount of "
, r* s, [2 K) O7 K "road. Either increase the amount of roads "
6 h# j" w! ?$ d& s5 ?+ i "by increasing the GRID-SIZE-X or "
, o# A& E! `* m: l "GRID-SIZE-Y sliders, or decrease the "
3 H/ k; _& [0 a7 N "number of cars by lowering the NUMBER slider.\n"
% Y; ~' A5 f: s1 z8 b, `3 s "The setup has stopped.")
$ P3 K- v& M/ A3 |8 N3 y1 [3 [( P stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color! X9 M+ Z0 \7 e* |8 b
crt num-cars. D& O$ v! A; S7 N7 i9 n1 ^
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setup-cars
" A$ ?$ B Y7 X set-car-color
: W( D2 Z* G h record-data
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% m- [/ j, o' I) ^7 |) n ;; give the turtles an initial speed+ D4 a8 u. q# j# k. B8 N
ask turtles [ set-car-speed ]# m+ R ]+ G1 v. _; e
5 o. _3 z0 K% |% b- Z# ^ reset-ticks
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. Y+ f9 O8 p4 h3 j) ^;; Initialize the global variables to appropriate values
' l6 T) S; J7 U; `) B$ c8 Eto setup-globals
$ x8 E; b( z0 T set current-light nobody ;; just for now, since there are no lights yet
$ Y7 b% p& Y! C# D" }3 ]/ \, v6 R set phase 0" a6 v/ A1 B' \- G2 a/ J5 M
set num-cars-stopped 07 t2 Z: i. p- D) j
set grid-x-inc world-width / grid-size-x
% Z+ Q6 O* E9 c- P7 d set grid-y-inc world-height / grid-size-y$ t) H1 s. q- \7 G! p) r% P9 q7 L
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
. Q% J% i) V8 x$ v) z6 S) Q/ _. x set acceleration 0.099
8 U1 i3 V* p' f. mend
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( L. }. g j4 q) L. ^;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
# M; ^+ D0 i9 e4 T- p* U/ j% n;; and initialize the traffic lights to one setting( q. y+ e( l% N3 [4 R1 S
to setup-patches( q/ Z/ `7 N- @& y$ K
;; initialize the patch-owned variables and color the patches to a base-color
& F. F- _% n3 S! V7 C ask patches% ?0 c" {5 D# X/ h
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& v0 \, [5 O/ d; Y* } set intersection? false( Q( [2 w5 G# P, K( }8 Z
set auto? false' {9 R- D# c2 t" o& F: q
set green-light-up? true
Q6 o" }; ]& _" X2 ` set my-row -1& F, Y( H W: u5 R1 B
set my-column -1& @# i/ F! @) E( F5 R
set my-phase -1- h6 ]5 q# e5 B5 i( H
set pcolor brown + 3, h# T+ x1 }0 t3 B/ L+ w
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;; initialize the global variables that hold patch agentsets: ~6 r5 I# X. u4 u
set roads patches with
* W+ K* J4 C6 Q* T$ w0 \) q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& W$ ^4 C& J. I! | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 N- B) R6 @4 d7 q3 \" T set intersections roads with
# Z9 `1 ~8 g' k! ?9 }2 c [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and3 y3 \8 p2 q, X" x
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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9 ? `; Q/ @% |4 q ask roads [ set pcolor white ]
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end
. e( f7 j' k- U# _其中定义道路的句子,如下所示,是什么意思啊?
3 {* E$ V6 C+ E* k- c# K set roads patches with
7 s9 p$ R) w# M: U& A [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; {! R$ j1 M) G1 O5 K W* l; X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
+ C+ q( ~ T1 ?- s y3 ^# a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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