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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。
+ m! P0 Y$ }/ o Rnetlogo自带的social science--traffic grid这一例子当中,5 T" p) U! |! F* a: M
globals3 E+ E; R' t D" E2 V1 h
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7 {' A, b% W: F | grid-x-inc ;; the amount of patches in between two roads in the x direction2 O. e( j7 `0 q6 o
grid-y-inc ;; the amount of patches in between two roads in the y direction) w' _* b1 z- n b5 h: B4 W# d
acceleration ;; the constant that controls how much a car speeds up or slows down by if
4 G6 a/ e0 J+ u ;; it is to accelerate or decelerate
& Y( E& ^- M/ Z4 K+ | phase ;; keeps track of the phase
1 j) n8 |) }7 K* `8 T6 _) b num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure! ~6 ?- J: c/ b; g3 M
current-light ;; the currently selected light
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;; patch agentsets2 t! @$ T* E1 k! e& F
intersections ;; agentset containing the patches that are intersections
& Y% R2 L" E6 Q, L- l" {% c5 s* ` roads ;; agentset containing the patches that are roads" |5 X# {, g+ ]5 s- Y5 [! M( T- R
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turtles-own- G, p& ^7 ]$ c" | d/ h4 h m( Q
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speed ;; the speed of the turtle
# @( B2 m0 p6 q* S Z up-car? ;; true if the turtle moves downwards and false if it moves to the right, l# p: W) l: R
wait-time ;; the amount of time since the last time a turtle has moved$ e" k& Q1 }: }+ t% l8 A: e4 X P+ S
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patches-own; t4 _8 t* }9 z* {& ?2 Y% S3 }
[
8 r L4 o) e+ ?- X intersection? ;; true if the patch is at the intersection of two roads
9 ^$ ^4 @9 W6 Q3 W" B green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 K$ D* ?, f& Q" k/ w7 _4 N8 }. R; U
;; false for a non-intersection patches.
; l9 I! B& B1 A my-row ;; the row of the intersection counting from the upper left corner of the0 R5 m: k4 I. T* I3 c+ L) `3 t
;; world. -1 for non-intersection patches. K4 Z1 c# _+ X+ k5 O' J7 x
my-column ;; the column of the intersection counting from the upper left corner of the% ^# x0 K6 |& W% U) B7 Y
;; world. -1 for non-intersection patches.( J0 Z2 ~0 Y I* k: ^
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
& v/ ?; p ^. P6 Y, ^* f2 I auto? ;; whether or not this intersection will switch automatically.6 R2 Q6 l6 J& V/ z- C" F2 H$ i
;; false for non-intersection patches.& \( R2 m+ x/ K( t+ X
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6 E8 m, \9 C+ H4 R2 y! [& u;;;;;;;;;;;;;;;;;;;;;;
. ^ i. O' P3 @;; Setup Procedures ;;/ U1 _( q3 [2 m7 T: }; Q9 t, ?
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
: g7 h; r6 Q4 C;; Create num-cars of turtles if there are enough road patches for one turtle to
* K x2 e( _% @" j;; be created per road patch. Set up the plots. j1 M/ }" F" X; Y$ A
to setup0 } [3 `! p+ S
ca
. ?1 K+ R: y; Z. J( y setup-globals
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6 R9 B4 J" i6 t$ t ;; First we ask the patches to draw themselves and set up a few variables
0 \+ L7 L$ G# p5 m2 f2 O setup-patches
' f4 p9 |! [7 L, {5 K$ l make-current one-of intersections8 {( p% w q9 K+ i& L: t% @* \0 [; G
label-current
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) W Q( z1 {/ j! W1 l set-default-shape turtles "car"% E4 F7 t+ P6 [, E4 G7 `4 c
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if (num-cars > count roads)
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: J F: U4 @+ k( K) Q user-message (word "There are too many cars for the amount of "
+ x C7 k x$ M "road. Either increase the amount of roads "5 z% \( q2 [; w7 i3 v; W
"by increasing the GRID-SIZE-X or ": H0 D6 ^+ ^& O, m8 E' q {( g
"GRID-SIZE-Y sliders, or decrease the "/ m+ A( y* g! s* E; A8 N8 p# ~0 ~
"number of cars by lowering the NUMBER slider.\n"
- P' Y- C' }3 d. U "The setup has stopped.")
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 G% k4 c$ U4 G4 A2 z U" t0 o& a( F crt num-cars
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setup-cars
8 A- @1 W; O/ Z% O: o3 t; A9 n set-car-color
# Y) V: o' l* W2 k record-data
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;; give the turtles an initial speed: N ~. m( z+ k, Z
ask turtles [ set-car-speed ]
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4 B, R/ H& E3 d2 _: ]+ r' r reset-ticks& L0 B: e2 C0 i: j
end
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0 t: ]5 D# u, n& N$ |9 q0 |;; Initialize the global variables to appropriate values# y: Y% \; ^- x+ r% R% P$ @! j
to setup-globals; e# C3 X: s" k5 ?3 Z( M4 t: n
set current-light nobody ;; just for now, since there are no lights yet. F( o5 L4 f+ c& Q
set phase 0) t$ Y# W, h0 |& v5 L! O' @; S
set num-cars-stopped 0
2 s) M4 k u, j( r) T2 g4 E set grid-x-inc world-width / grid-size-x
. S- p8 |* j% E set grid-y-inc world-height / grid-size-y* P$ r/ p9 W( l& N `
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
) F5 n9 ^* M9 Y: o- N# j; N set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
: i D% @' E2 C5 l* U# a2 J;; and initialize the traffic lights to one setting3 u: V8 s E, B
to setup-patches( G0 `) o# h6 [% J; Q$ m' ]6 W0 E) O
;; initialize the patch-owned variables and color the patches to a base-color
a$ Q/ w3 h$ s( r6 {9 o3 h ask patches/ @7 I; [9 b+ n6 M! V
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2 ]; J% H2 B6 _; i0 n0 i" @ set intersection? false5 C1 M( [9 m& ~% b; {2 ~
set auto? false
+ R' @* [! j, r2 y set green-light-up? true
% u+ L: z1 k; B set my-row -1+ _4 V8 r2 K' ~# @% }( p8 N
set my-column -1
L* X6 [: y X( e# M! [ set my-phase -1
1 c1 ?! @; ?% y4 @ set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets# C" M! c6 U4 \2 `5 L( b& {
set roads patches with
# G$ j" x8 ~0 L _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- y# s8 g' k4 } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ E8 I1 M" S6 e# s- m
set intersections roads with
( y/ ~' k1 E$ [, A5 C8 P2 X% a' K% O# T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and# N( D+ f9 D+ c8 ^1 r! X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]" k4 ` f$ V% `. Q* d* i% i/ z& Y
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ask roads [ set pcolor white ]2 i: r! j) N# d! b+ @% V+ u
setup-intersections: A9 `6 H+ o" I/ Q) R
end- ?8 u+ D; u2 e# H( m( Q& B: X5 M
其中定义道路的句子,如下所示,是什么意思啊?$ _! b( O4 Z c4 ]+ F: A# `
set roads patches with. c" M9 R+ J/ r1 T+ T' E2 `
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
5 J5 t2 V5 U6 W (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( y9 N [: D1 h) ^& N9 e! [
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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