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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。
# a/ ]4 y: _1 q3 v3 N1 T( Ynetlogo自带的social science--traffic grid这一例子当中,
; H9 g8 Q s/ @5 u/ yglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction9 f! w9 A2 S( r# B- r
grid-y-inc ;; the amount of patches in between two roads in the y direction
: ?: z$ X2 [0 }( S. B( f d acceleration ;; the constant that controls how much a car speeds up or slows down by if6 p" t- ?, b L/ ~) D8 N
;; it is to accelerate or decelerate
- j6 n' L6 B# ~: d7 S- K; U phase ;; keeps track of the phase
; i- ] E7 E7 ]+ }$ M num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure7 `; M5 X' G3 _$ |7 H3 N% Y
current-light ;; the currently selected light
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8 _7 `9 z1 }% z0 l7 A% Q ;; patch agentsets w5 D1 j3 c8 ^8 ]$ n$ R
intersections ;; agentset containing the patches that are intersections
& G( U l* z/ V roads ;; agentset containing the patches that are roads
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1 [7 S! z7 ^: F: p. S4 C; z, Qturtles-own
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" S* b2 P! \! A0 {6 c' h) Q speed ;; the speed of the turtle5 w* S m. f+ ~
up-car? ;; true if the turtle moves downwards and false if it moves to the right
) H) j& d* K; E1 B wait-time ;; the amount of time since the last time a turtle has moved* w2 t0 y. l9 V" x) S4 i! b
]
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. Y, _9 I2 }* A- c# b* i# A) {/ Y- K: Jpatches-own
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/ [0 K+ l8 T% y9 ~ intersection? ;; true if the patch is at the intersection of two roads
3 }2 n% F8 ^+ |% p' [: Q green-light-up? ;; true if the green light is above the intersection. otherwise, false.8 a$ S7 f, A8 q6 T4 Q
;; false for a non-intersection patches." ?% [( c+ C% S; r
my-row ;; the row of the intersection counting from the upper left corner of the$ f, `, W3 j+ Y* b
;; world. -1 for non-intersection patches.9 l; }" k R+ O+ o. H
my-column ;; the column of the intersection counting from the upper left corner of the
8 O2 g0 ^- l0 @' } ;; world. -1 for non-intersection patches.. n5 W, O a) I' x
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
* x; q( K- B7 l- t% H9 V auto? ;; whether or not this intersection will switch automatically.- Y$ k' h# o& [* E8 c
;; false for non-intersection patches.
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( _" E/ U, p9 k! C7 U;;;;;;;;;;;;;;;;;;;;;;
' n5 p$ u# N8 y* ^& z, b& _;; Setup Procedures ;;
/ R; Z4 M; ]# ^;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
& g& c7 W7 U3 m: o1 d4 d;; Create num-cars of turtles if there are enough road patches for one turtle to
( R) e: R( R& A8 B ];; be created per road patch. Set up the plots.% E; S3 M6 G- p {1 L6 I
to setup/ m1 }* @0 q7 X" T) r( a% l5 B
ca
9 [6 U9 `$ T6 l3 y. P setup-globals& C, e( K4 }6 l9 A1 {
, G; }2 { N' h( X J; u ;; First we ask the patches to draw themselves and set up a few variables6 d/ A3 V7 ^) B( c
setup-patches
6 A" i6 U( G0 g- E1 N make-current one-of intersections( y* _1 X# @% r! W Q
label-current. ]7 b3 d6 L5 S# E Z- X' e
. n1 Q3 L9 L2 \( r set-default-shape turtles "car"8 J q( ]( v f! q# {, M: z1 U
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of ". E, F% K1 s( N$ }
"road. Either increase the amount of roads "2 @2 F/ ]2 B/ l+ E1 o7 a
"by increasing the GRID-SIZE-X or "( K# r; W% U: N; f& Z4 p
"GRID-SIZE-Y sliders, or decrease the "
" C* u1 ^3 o. j2 V' Z( k, \ "number of cars by lowering the NUMBER slider.\n"" F! R- ?; j. S5 ^7 A% ?& d
"The setup has stopped.")
6 J& M3 N, ~7 R. j stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
! P8 o9 O3 T1 y% r+ L crt num-cars* W) \$ ~! t; C
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setup-cars
4 G: o* t9 T; U set-car-color, Q3 G# h$ C) t& t& D
record-data; p9 W6 ] b$ q+ ~+ D7 I0 \! T
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4 a9 J! E% V5 Y. ?- r/ t% a* G5 d0 [ ;; give the turtles an initial speed
4 M1 F) }+ p0 |& S- B7 m ask turtles [ set-car-speed ]7 _ b2 a+ y7 ]( w5 f. i) n% m- v( E6 x
+ e" w5 r: h6 q' B: Z6 D reset-ticks
& _- G/ y! k. {end0 j) T9 a9 V; V* U
O G* b1 s9 I;; Initialize the global variables to appropriate values4 T! R) W! j8 W0 }
to setup-globals3 Q& W9 o/ S0 o, |) z- ~! b
set current-light nobody ;; just for now, since there are no lights yet7 G8 y/ A S$ z4 t- H* f
set phase 0
$ M& Y$ q5 y0 a& V1 L5 t8 \ set num-cars-stopped 0
: `, `% G3 g9 g% Q6 B: x, b set grid-x-inc world-width / grid-size-x
6 g4 j* T* U/ {: M( W: a. C7 k set grid-y-inc world-height / grid-size-y
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0 B) m$ q4 y$ l b% @ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
" e+ B$ B: M- w+ E+ { set acceleration 0.099. O8 r: b. p4 C
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 i$ I9 B$ q( G% t, [+ H1 ^;; and initialize the traffic lights to one setting
; a5 x. h, \* V* T% g& u, Qto setup-patches
# C# g6 e6 @9 @6 \+ c0 C ;; initialize the patch-owned variables and color the patches to a base-color* K8 R9 v4 B5 l0 Q" h+ I+ e
ask patches3 x& H3 L- H. F8 T w! B
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- z' F/ m$ V. q0 o set intersection? false
* s5 t6 ~& Q' w N# p* f set auto? false
- ?: i4 Q2 T( C1 |8 C& @$ S set green-light-up? true
% @( l4 ^7 ~& E8 v* F set my-row -1/ E+ {- Q/ _" [; B) \' M, d( W
set my-column -1
7 ^: m* R1 S+ f' n2 x- `, V set my-phase -17 S3 Q. N" t9 N1 _: X
set pcolor brown + 3. ] v: v# f) }/ V2 }% T# ~
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;; initialize the global variables that hold patch agentsets2 ?9 w" J8 l# R4 v' L* W9 j; A) b
set roads patches with5 L7 d; P* w3 `8 N
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& z- p8 l8 Y7 V* ? M, G( M6 [
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 M) @$ |. U' u1 P$ z set intersections roads with, q4 n) k" o+ E% N& T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
3 ] r) H$ j r# v& K (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% D; l% F" a4 O! y; F
- k1 m$ T4 b1 w# I1 i/ n% ?& V! @ ask roads [ set pcolor white ]
) M5 v+ D. _1 s: b. C setup-intersections7 E) }. u" e9 ~% @7 r# N! T
end. i- F# `& G8 l) } t7 i5 m
其中定义道路的句子,如下所示,是什么意思啊?
9 Q9 c% Y/ ^8 U H" e$ k: J+ [( F set roads patches with! `6 J. l2 G3 _% M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 z3 o' |: Z7 j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- g* M4 a+ U( L' I! t+ U$ K
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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