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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。% S4 y: ~1 ~9 G8 s' z* J
netlogo自带的social science--traffic grid这一例子当中,3 P" }* h* ^8 H- B1 ^
globals# S9 G F. n- [8 ]3 t, x5 c/ O4 F
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grid-x-inc ;; the amount of patches in between two roads in the x direction+ ^/ [% }9 x3 p4 m
grid-y-inc ;; the amount of patches in between two roads in the y direction
! }+ @( t" }% y6 Y* D' J9 E acceleration ;; the constant that controls how much a car speeds up or slows down by if, c* v) m9 w9 y w$ {2 R
;; it is to accelerate or decelerate" w. m1 Z' `6 H
phase ;; keeps track of the phase
; N: a3 E2 \- Y: ]5 o3 O num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
0 w+ u0 \6 f6 k current-light ;; the currently selected light
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5 Q' h9 i2 }( S& N, Z o ;; patch agentsets- a/ e7 g" f D& z/ w
intersections ;; agentset containing the patches that are intersections
& Z* V/ U; k' U6 I$ x9 h% @6 I* p roads ;; agentset containing the patches that are roads
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turtles-own7 E- s; \$ l/ V- n
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speed ;; the speed of the turtle& A, e+ v, [+ G1 v$ c. a
up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 G A4 L* e% @* c/ \, z% B wait-time ;; the amount of time since the last time a turtle has moved) t: x- m2 o# \0 E( ?
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
5 ^, N3 E; f# p3 W3 e6 l green-light-up? ;; true if the green light is above the intersection. otherwise, false.6 f! N5 E. d {- g
;; false for a non-intersection patches.$ C4 G m# O( w6 [8 B
my-row ;; the row of the intersection counting from the upper left corner of the
* S+ v( C, @5 Z( v% t ;; world. -1 for non-intersection patches.' _4 p: |* r+ l1 m
my-column ;; the column of the intersection counting from the upper left corner of the
& h5 `% q5 R. L* O ;; world. -1 for non-intersection patches.
4 g( k- k8 @! Z; |- L% R7 f my-phase ;; the phase for the intersection. -1 for non-intersection patches.
) \" X" ]3 C& o8 P ^ auto? ;; whether or not this intersection will switch automatically.3 m/ D5 V' |) h7 J7 ~. b. n5 q+ a
;; false for non-intersection patches.: ?7 t) z& y2 B5 w, e2 J* N, h' Z8 E
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;;;;;;;;;;;;;;;;;;;;;;
$ T/ ]: l- F {! p;; Setup Procedures ;;
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- ?- N- w( S) Y; Y; }' i1 W;; Initialize the display by giving the global and patch variables initial values.
# |0 X) P9 b3 z& n+ i0 a;; Create num-cars of turtles if there are enough road patches for one turtle to+ G# j4 Q" u$ ^; ~4 j: g1 i# n
;; be created per road patch. Set up the plots.3 i4 a# `- g7 u+ l: \2 A. o
to setup' {3 A0 J4 N( [' w) W
ca
5 n" G) t3 S" G; V8 t5 y0 W1 z1 | setup-globals# Y; F6 N" r+ n$ H- S( J
- M. p' I, O1 i5 h5 y, F ;; First we ask the patches to draw themselves and set up a few variables. n# i1 H8 J. n% I
setup-patches
- \* R! _9 X9 I# R5 ~% b- ]" q: W. Z0 w make-current one-of intersections" ?$ ~* d- V" _! V% I3 u6 ?
label-current
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set-default-shape turtles "car"2 k+ R, [9 b2 U
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if (num-cars > count roads)
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& m- W8 ]* H/ K4 F5 Z" F user-message (word "There are too many cars for the amount of "
3 k. f1 w6 j9 ]" q5 m1 f "road. Either increase the amount of roads "4 o' a& N4 R: a! E1 \$ |* Y& d
"by increasing the GRID-SIZE-X or "* h7 P; H2 y% U v
"GRID-SIZE-Y sliders, or decrease the "
8 |. Z) ^& l$ O1 q% [ ? "number of cars by lowering the NUMBER slider.\n"+ r1 Z3 o- I' i* W" N4 O6 m
"The setup has stopped.")
3 \ j+ q: z4 t, u# p" s2 y$ j stop% v6 A- h( f" }- `7 Y; R2 B
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color6 Y) d& t1 g4 ~4 a" c
crt num-cars
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setup-cars
' z. k* N$ [; q$ c' h! Q set-car-color
5 Y6 `. T& p4 z1 [$ Y5 c! I record-data8 @& n& X3 M. j, b! {
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;; give the turtles an initial speed! o. k/ b0 X3 ]- r7 j4 `
ask turtles [ set-car-speed ]$ ^0 t* f3 S- Y& P! N7 p' c- j
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reset-ticks' O0 H" o" B3 ?" I
end
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;; Initialize the global variables to appropriate values
% {' s( X/ D( S @; k# d* f+ r5 Y. eto setup-globals
$ z6 a2 ~6 d5 P( p set current-light nobody ;; just for now, since there are no lights yet4 I+ P# W% ~5 Y* x* ^- _# }9 G
set phase 0: Z' X' M& k# U" M3 A5 z/ C
set num-cars-stopped 0
# z: ]; F( x7 j9 ?, K6 C set grid-x-inc world-width / grid-size-x# w9 E9 y( m$ ]5 ~3 H, b+ [
set grid-y-inc world-height / grid-size-y+ U. k1 }/ K @
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
% f) v- U. X9 a8 T3 H, \ set acceleration 0.099. W d* [/ e' P, B* x: c
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' K% }5 N0 i7 |; i;; and initialize the traffic lights to one setting
1 H- [6 u, t/ W2 u; ato setup-patches/ D2 K$ Q' i C7 t4 X) g1 s
;; initialize the patch-owned variables and color the patches to a base-color1 T( P0 @) z# G4 r- U- {3 h4 H
ask patches: ?( [; o: t6 j! y* j6 U
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set intersection? false' B( g) \" p1 o" E2 c2 P, }! W
set auto? false$ y$ U' l' ~" p0 U7 F& j
set green-light-up? true
4 d m$ v: [6 K$ t. u set my-row -1
9 s' n, ?0 y" ]; L5 f set my-column -13 X" G4 t8 ^+ P7 g
set my-phase -1$ V: v9 Y# ?1 D$ D: f% N! a# m
set pcolor brown + 3' ?7 b7 y9 Q4 O& V, `3 `0 m
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;; initialize the global variables that hold patch agentsets b/ ~5 J& K7 `
set roads patches with/ W2 `) W6 G# d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# ?6 R$ d8 q, \* { (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- `9 w6 @8 G1 V* ~6 E6 C! n2 y set intersections roads with
( q! v5 {* J* ~$ X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
! ?; x, z# |. F4 U& Q/ s (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. ^: w/ p7 @' |
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ask roads [ set pcolor white ]
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end
7 [& Y: Z0 t+ q6 K其中定义道路的句子,如下所示,是什么意思啊?# v, u* U0 I3 v% S9 H* v6 s# J
set roads patches with
; ~6 W- S2 q* N4 [4 S" ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. A" v/ ^/ h, q2 Z, r2 u, {6 K4 d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& E* L. {3 R* S
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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