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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。5 b! Y8 h6 P9 ` n5 ~& x% [, M
netlogo自带的social science--traffic grid这一例子当中,. `) W: a4 W9 f
globals
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; F- W8 J! f' S grid-x-inc ;; the amount of patches in between two roads in the x direction$ Z: \' t& p4 Y
grid-y-inc ;; the amount of patches in between two roads in the y direction
& O; _4 ~3 S7 a, b acceleration ;; the constant that controls how much a car speeds up or slows down by if
1 F/ i! O. {+ E3 v* w+ ? ;; it is to accelerate or decelerate& \- ^) t8 `& d- U% |% L
phase ;; keeps track of the phase0 c I- y" V$ q7 f- I! [
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
9 m+ n/ C) j2 j9 l2 h0 x: z/ d current-light ;; the currently selected light
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1 x0 I9 h. o, U+ z! u5 q ;; patch agentsets& r \- g- H6 ^, o6 F- O( y
intersections ;; agentset containing the patches that are intersections
6 K- P7 Z# U. ] roads ;; agentset containing the patches that are roads( ?0 d& r6 {- A4 j3 E/ G
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turtles-own
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speed ;; the speed of the turtle
1 A, }8 m$ K6 E up-car? ;; true if the turtle moves downwards and false if it moves to the right
: }7 d) f: G1 k: [* h" T wait-time ;; the amount of time since the last time a turtle has moved/ C) S: r. C' i, L
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patches-own
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% ~5 P* M) {! J3 F B6 c8 V& Q: ` intersection? ;; true if the patch is at the intersection of two roads
4 a9 G: a' X' P/ |7 \, u green-light-up? ;; true if the green light is above the intersection. otherwise, false.6 k# c5 l6 P' N5 w
;; false for a non-intersection patches.
6 N7 Z- r' E; x) B" I my-row ;; the row of the intersection counting from the upper left corner of the% p) J1 C$ ?0 {
;; world. -1 for non-intersection patches./ S7 h# V0 g, w& F- s z, q" L
my-column ;; the column of the intersection counting from the upper left corner of the
: l. }' S7 j6 C" K ;; world. -1 for non-intersection patches.# Q+ m* T8 ?$ N2 Y% G1 b
my-phase ;; the phase for the intersection. -1 for non-intersection patches.6 l) k6 A/ Y; _. c2 P
auto? ;; whether or not this intersection will switch automatically.3 Z- X% t8 N( k9 H+ o
;; false for non-intersection patches.2 S* s( J( `9 p% J; w+ O1 o; P) ~$ }
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, M( Y* X9 f+ r) c;;;;;;;;;;;;;;;;;;;;;;0 j' A& t. R {( G7 E: J& h
;; Setup Procedures ;;: Q% Y" i, G( K9 s5 s9 W8 q
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
$ M) ?7 j2 ? q! R. W1 h% N;; Create num-cars of turtles if there are enough road patches for one turtle to
# u/ e& J6 c4 X! o;; be created per road patch. Set up the plots.
5 ?: T& J5 t( Q S9 ^, Uto setup
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2 b m5 t8 r. ^) k# O" H, n3 B setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
# a+ s' r4 f; D' E* z7 ~ setup-patches
) N( a5 J3 S" @0 N( l) b3 @" L make-current one-of intersections, o- |" S9 z; a* |4 O' V
label-current
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) M# ~- p1 ]- N! M set-default-shape turtles "car"( w. b% D6 p Q: v' g, b$ c$ H
! a6 a a( @: a$ u3 y if (num-cars > count roads)
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0 {' R4 L& W. a: W; S$ a4 w user-message (word "There are too many cars for the amount of "7 Z4 }, A) n6 s1 a
"road. Either increase the amount of roads "$ e$ ~& o, C9 ~* s& R x( ~+ p
"by increasing the GRID-SIZE-X or "2 L4 ?. {: ^3 [( ~# Q
"GRID-SIZE-Y sliders, or decrease the "
4 g% B' W6 i" F8 b8 {. A5 I "number of cars by lowering the NUMBER slider.\n"
# L o+ {8 [5 o6 m1 U; [+ T "The setup has stopped.")
0 J- P" Q2 D, h) N; u, ^2 d stop- N) e- g5 }3 K0 v( E
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0 ^! R3 a2 u0 }4 ? ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color; j7 F4 f2 q6 P; K
crt num-cars
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5 i2 z, J7 r T; F$ K/ O. { setup-cars: `4 Q+ E' G6 ^2 v' u
set-car-color) x& U; D( |; [7 E: W5 o
record-data
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;; give the turtles an initial speed" E8 o$ T. Y+ {6 R* B' J
ask turtles [ set-car-speed ]5 G4 K! _, f9 t- t
|: A( M }3 B7 c reset-ticks8 q( Z9 Z, S* ?/ u9 x
end
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;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet. k( ~* Z1 E+ R6 V: s, J
set phase 0
4 |- u V$ P6 t2 p0 g" d. H set num-cars-stopped 0! _6 O% `+ W/ J: t. z% ]" t
set grid-x-inc world-width / grid-size-x9 ~7 e6 [' e- ]6 f3 A
set grid-y-inc world-height / grid-size-y
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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& o+ }* Q8 ^6 @% v5 `/ A, u+ g set acceleration 0.099$ R: A! V" j3 {
end
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; p8 f! ~/ R2 F$ u! t;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
V% b' J% l+ u( o& M;; and initialize the traffic lights to one setting
a/ G2 V. o. o, C6 A! {to setup-patches: ]! l- I( E& p
;; initialize the patch-owned variables and color the patches to a base-color, V9 C7 G4 Y- D% N+ I
ask patches
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set intersection? false0 J( x1 ^$ i9 k; R* r" o( H( z' l
set auto? false
4 O& x7 |; R6 [. A6 F& M7 o1 H8 Z set green-light-up? true3 l9 c: u; k0 F
set my-row -1
. ]+ X- l3 b& f' _/ @* O set my-column -1 X+ V! e7 V0 c( P1 y! s9 m
set my-phase -1 Y v; f/ y2 f7 ]
set pcolor brown + 3/ L2 H0 t. z r v& i( Z' H# n
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;; initialize the global variables that hold patch agentsets
, V% g3 c2 C8 D9 G8 s9 }1 L set roads patches with
% [6 X: _* j' w& I0 m( @1 g& e [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ O9 g! y) g4 w# P9 t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# C& a" \( j8 m* G set intersections roads with6 [# W/ B4 U5 w8 z) A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
' {! Q/ C# I0 q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% f |/ z" I3 y! g/ G, _
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ask roads [ set pcolor white ]
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end
7 h& b& h. e+ q1 g& [' L# O8 p其中定义道路的句子,如下所示,是什么意思啊?
- ]5 ?: Q4 {2 B set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* g8 N/ a- F- h5 s8 i7 r3 F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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