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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。
% R( V5 @/ d& D4 G& ]% Anetlogo自带的social science--traffic grid这一例子当中,& D& d1 ?8 s# R) K3 M
globals
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& [; U6 {! @8 x0 _4 N! V' s grid-x-inc ;; the amount of patches in between two roads in the x direction
! U% P0 \- w+ b0 ]; o grid-y-inc ;; the amount of patches in between two roads in the y direction' s9 b! L& x# D6 s Z
acceleration ;; the constant that controls how much a car speeds up or slows down by if
- {. f5 B; m; i% [5 w ;; it is to accelerate or decelerate" B( [/ p, J S9 ]) ]4 P
phase ;; keeps track of the phase
9 y. v% _: u/ F0 I( w num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
0 n: K/ x% `( ~9 s6 J! r k, ?* {3 b current-light ;; the currently selected light
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;; patch agentsets
) _4 }! ]8 A- p! t4 _ intersections ;; agentset containing the patches that are intersections
0 A# U7 W9 f0 J roads ;; agentset containing the patches that are roads
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turtles-own4 F$ d8 _, \' R# t$ D
[
$ L" f* p1 i/ @, l% v speed ;; the speed of the turtle
. p4 q7 {8 _8 D$ S6 { up-car? ;; true if the turtle moves downwards and false if it moves to the right9 ^! I" c& A C2 d. L* T
wait-time ;; the amount of time since the last time a turtle has moved
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4 v# Q. j" }4 y2 N% O% t; Fpatches-own
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; F& \) ?4 ^ e% l intersection? ;; true if the patch is at the intersection of two roads. w1 q3 e, Z; Q1 {+ K
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ L- w# r9 D2 L: F( \2 n. _' ? ;; false for a non-intersection patches./ p) s1 ^1 m2 u$ a# q
my-row ;; the row of the intersection counting from the upper left corner of the
/ h# R; ], Z! R/ x ;; world. -1 for non-intersection patches.
8 W5 {* W; `4 Y( i& ~+ n$ ]4 M2 ^. I, ^0 R my-column ;; the column of the intersection counting from the upper left corner of the I7 L+ W3 S1 E+ q2 `! Z
;; world. -1 for non-intersection patches.
9 k% v6 v) j. o my-phase ;; the phase for the intersection. -1 for non-intersection patches.
& d" B) u7 U& `+ B* Y0 i1 b5 W9 [# e auto? ;; whether or not this intersection will switch automatically." j% j5 F1 h* S t9 y4 j5 U
;; false for non-intersection patches.) g' e ^+ s* K8 q" y' V% E
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;;;;;;;;;;;;;;;;;;;;;;
- g+ B+ `; @* K% r: m3 b. q7 v9 {;; Setup Procedures ;;0 x" f& V) ^& e9 ~2 m3 L7 O
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.) h0 D `2 n% ~
;; Create num-cars of turtles if there are enough road patches for one turtle to }7 g) W1 U4 e3 [. N
;; be created per road patch. Set up the plots. k Z: P$ t' V; U. _( ?
to setup
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setup-globals
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# Y* ~: w) k* a/ h ;; First we ask the patches to draw themselves and set up a few variables% f0 B V% p2 k
setup-patches2 h: I) O% |9 W. R1 @$ u7 x: ]
make-current one-of intersections
6 L# Q7 h3 F+ E& L label-current
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set-default-shape turtles "car"7 q( o I- h$ S# [5 L6 D# [) C: I$ L
0 t5 L5 f: t& s if (num-cars > count roads)) B9 E7 R6 S+ W
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user-message (word "There are too many cars for the amount of "
- @4 }- S t7 e7 N "road. Either increase the amount of roads "
. Y9 ^) Q& d$ D/ L& I- s "by increasing the GRID-SIZE-X or "
1 R1 P! p% h5 N/ d "GRID-SIZE-Y sliders, or decrease the "# ~$ z) x/ x2 V; |
"number of cars by lowering the NUMBER slider.\n"
* {3 I% q5 r& t! B k8 n9 A "The setup has stopped.")- {' J' U6 M$ g$ W
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 ?" c" y& W& H: m$ X4 C crt num-cars
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7 `7 R( j/ K9 y! M) _2 `/ C setup-cars
4 I. H* N. |! N+ k set-car-color
0 E- }/ I! J' [; Q; f9 U record-data3 r' I8 E9 h5 ]5 _
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;; give the turtles an initial speed% I7 F$ z% R( \4 v5 I$ J
ask turtles [ set-car-speed ]
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reset-ticks$ r6 ~ q0 w2 z5 g' |6 |
end3 }, i" Y9 ?, A( m* `
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;; Initialize the global variables to appropriate values
! a7 Z' M7 O! ?4 H3 u1 vto setup-globals
j! _! ], @+ I6 P! S set current-light nobody ;; just for now, since there are no lights yet* Y& h" M( o* }" Q3 H: S
set phase 07 C" k1 H* S/ M% J/ Z' D9 [6 w5 [! c) O) Q
set num-cars-stopped 04 q* a6 |& c8 y4 A
set grid-x-inc world-width / grid-size-x% ^/ e3 V( h- o" B
set grid-y-inc world-height / grid-size-y" Z' b2 w; r0 H" K% ]4 _1 w, z6 N
1 P( `. C. O3 j4 y& _* g7 k ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
7 M7 S3 p; \8 \) I set acceleration 0.0997 B3 W) n E3 a& e$ X* z: N
end4 ^! }% `- F4 W: R
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,' |; J9 U/ {' c& t1 W
;; and initialize the traffic lights to one setting( j( N Q1 J! ?0 m
to setup-patches1 F0 ~7 R- T& k1 W
;; initialize the patch-owned variables and color the patches to a base-color& c& l4 X6 s! Z9 Y3 e
ask patches) B- e: G5 b& g0 D. }
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' c& C( p0 ^8 \6 ` set intersection? false- o, C3 ^ G7 j+ T9 G5 N
set auto? false
0 p8 Z. P+ R- S set green-light-up? true! H' a M$ U) z+ k8 _
set my-row -1
4 l6 n* p0 e2 G. M set my-column -1
/ x0 N5 R o7 t7 Q0 W" m7 a- T4 y set my-phase -1
2 l) r Z" Q" v/ @3 E set pcolor brown + 3
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# M) o1 [4 u- Q7 E* l ;; initialize the global variables that hold patch agentsets4 A8 e9 t" A4 Q+ I3 C; F4 |9 {
set roads patches with! {% \: t7 {) |$ J
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ i% _& z+ h3 u8 k! { (floor((pycor + max-pycor) mod grid-y-inc) = 0)]: K- c, V! J0 c J4 h/ @
set intersections roads with
& I! x9 O, \5 |# y7 I) m1 [+ j [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and" f$ t- x9 h z% q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ U2 ~, J, d* D! I* N
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ask roads [ set pcolor white ]
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* I) c& j, N7 [4 z* ]7 t8 _其中定义道路的句子,如下所示,是什么意思啊?
& V* e D1 y2 X! f* P# l) r set roads patches with
/ E5 J6 ]1 q8 N) { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, N; }3 r6 f& y (floor((pycor + max-pycor) mod grid-y-inc) = 0)]! _$ h( v0 `" C# J6 J
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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