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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。) E/ n4 K6 N; `) o5 o3 F
netlogo自带的social science--traffic grid这一例子当中,# S; N' c% h& w9 ?8 k" z$ ~ `1 v9 B
globals+ t! r4 S2 P4 V, u
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& q+ g1 c0 D5 Q ^- ?! } grid-x-inc ;; the amount of patches in between two roads in the x direction
; L [4 f2 V# { grid-y-inc ;; the amount of patches in between two roads in the y direction
; A/ R6 j6 O9 A9 N7 u$ [8 K. e4 ~ acceleration ;; the constant that controls how much a car speeds up or slows down by if
+ d- R3 G' }: Z; u) L* f2 l1 b ;; it is to accelerate or decelerate: s/ A4 |" X) ^9 Y! D' h
phase ;; keeps track of the phase
& T1 S Q y6 E8 B num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
' o7 T" E, i. V8 H current-light ;; the currently selected light" ^: x6 q! V4 u; R
. W! g3 b x$ s ;; patch agentsets# }% V4 T& ?- j- Y
intersections ;; agentset containing the patches that are intersections( {; Y0 y0 a3 \
roads ;; agentset containing the patches that are roads
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. `* ~# ~% W( {1 S: t6 T' oturtles-own
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speed ;; the speed of the turtle
8 r5 I) {; c5 ^9 c up-car? ;; true if the turtle moves downwards and false if it moves to the right; |2 W/ }* f% b3 E+ {" G$ Z
wait-time ;; the amount of time since the last time a turtle has moved
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) k2 w+ y: [" g$ ypatches-own
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9 r0 A" N G! c) n( T' v) y intersection? ;; true if the patch is at the intersection of two roads
# ^& J% ^; e2 [1 u green-light-up? ;; true if the green light is above the intersection. otherwise, false.9 a% K# ?: } U+ p
;; false for a non-intersection patches.
( Z+ `: y% x L" p- g B) @, S my-row ;; the row of the intersection counting from the upper left corner of the
4 I. }8 c0 H( q. ]- N ;; world. -1 for non-intersection patches.( q! W! ~* ^0 Q/ F! ^' H
my-column ;; the column of the intersection counting from the upper left corner of the/ R8 u1 n9 }3 I+ W3 B0 Y3 i- E: [
;; world. -1 for non-intersection patches.
( q; [0 L9 c t- P my-phase ;; the phase for the intersection. -1 for non-intersection patches.
$ H. F' Y, a/ Q# q auto? ;; whether or not this intersection will switch automatically.6 p5 R! c' _7 t+ f ~5 ~
;; false for non-intersection patches.: z6 K# v! e. ~; T. L% M) k
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;;;;;;;;;;;;;;;;;;;;;;
2 P8 Y" l: ~' g" z5 f;; Setup Procedures ;;! l. T: i; c0 N5 V9 C% D1 _: K
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
\, r, N- J/ O! f! p1 C( N;; Create num-cars of turtles if there are enough road patches for one turtle to# L, m4 |* w) B- \5 Z
;; be created per road patch. Set up the plots.
, f Z6 O9 ?8 D( b& x- zto setup
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setup-globals2 d8 R- i4 N% @1 Z$ U, v
$ H' f9 V" l8 L$ q& a. a8 | ;; First we ask the patches to draw themselves and set up a few variables& ~8 e# z( E! T8 r
setup-patches c$ |; N' t+ M- t) d" y' f6 P
make-current one-of intersections
8 Q6 e; s6 ?' c# ~6 L9 W label-current% j; T7 q8 `. B# M( E
; V9 N F5 l( o; o set-default-shape turtles "car"
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if (num-cars > count roads), B3 V7 c- h7 J, v
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user-message (word "There are too many cars for the amount of "
! z0 l9 t" l2 ^ "road. Either increase the amount of roads "
- x& a; v0 i% D/ Q' S8 j5 g# j "by increasing the GRID-SIZE-X or "
; K. x' P. L) A5 ?* q9 _2 D "GRID-SIZE-Y sliders, or decrease the "/ I6 v2 D% x7 R- D. }
"number of cars by lowering the NUMBER slider.\n"
/ b1 h4 H' s# S4 i5 r! I! }% h "The setup has stopped.")5 K6 R/ H/ [& g
stop+ c% ?$ L9 J2 Y l3 o0 O
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
% s# I0 a* n* P3 l8 u crt num-cars
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. _, A5 H4 y5 i, c setup-cars! J a7 E& b" c% M* B
set-car-color6 V' b" k9 I4 R$ w
record-data
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; G7 ~) W% Z: O* ? B ;; give the turtles an initial speed
- r% Y9 M- b, D3 R% P' @ ask turtles [ set-car-speed ]
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3 C. B9 M1 j6 f, H$ h [ reset-ticks- b, O! E8 k l Z. Y; }
end) `0 \6 T7 y0 w
1 v0 m9 b8 t. @* _( g/ m;; Initialize the global variables to appropriate values- H5 T* `# {$ z W, L
to setup-globals7 z: _# G% Q. l) R7 F1 ]/ W/ h* Q6 ~4 m" G
set current-light nobody ;; just for now, since there are no lights yet
# @4 R; O8 k x1 S4 I* J5 C d set phase 0
6 |4 I8 ~% y( J5 J set num-cars-stopped 0
* S! u# I9 B% f5 v# G set grid-x-inc world-width / grid-size-x# ~9 m- x9 W" b" ~% w8 |% K
set grid-y-inc world-height / grid-size-y- h9 q" K: _& s) j# b# 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$ D& J7 S( D: t. ]! o
set acceleration 0.099
$ _- ?( [# @0 v9 X( \" iend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
. y9 G$ b+ q4 l& {! L6 ^& ~;; and initialize the traffic lights to one setting4 R! _& u0 Y' }4 M6 V: W9 c
to setup-patches
7 v5 _* H+ `0 V& I$ h5 [ ;; initialize the patch-owned variables and color the patches to a base-color" B5 k7 D v' W. K* D
ask patches4 a/ |% F; p% o; ?
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set intersection? false* t" V# J9 E& @( ]
set auto? false ?4 K6 T" r+ I
set green-light-up? true
8 l$ o2 A x; Y. w set my-row -1. f1 L$ G* l7 ]6 _. d6 d; U* |5 f# d
set my-column -1& @ |8 m% @ M1 J" O- G
set my-phase -1
( h, b, z8 [; b M$ k set pcolor brown + 3% M7 I5 \7 q. H3 u$ K$ H
]
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;; initialize the global variables that hold patch agentsets
/ l `6 K' B2 T P+ l set roads patches with* p. v4 ^0 A) ?, m0 o/ \! I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' e5 C: Y1 L5 o& t/ @5 [, F# }5 B
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]( ~- i4 b6 f8 P' G0 x
set intersections roads with
, \+ f& Q- ^% {0 w! ^2 k# k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and, w1 B8 S% ~- u# e4 g' S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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B5 O8 Q9 G7 Y, V+ l8 b ask roads [ set pcolor white ]
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$ n+ d( H i3 K) |: p6 z7 e其中定义道路的句子,如下所示,是什么意思啊?8 P. ? u% ~$ ~* t4 H
set roads patches with
N6 D! w5 Z! ?( A Q v" w [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
+ ` Y/ c9 t( s, Y. Y# z3 @$ @9 w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 N+ \8 p' j6 [: h5 U
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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