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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。
7 B8 l& d# Q6 Q: A: b5 wnetlogo自带的social science--traffic grid这一例子当中,( t8 U9 q, B; ^+ Z6 B' k
globals6 e# G" t4 P7 O( N8 x
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grid-x-inc ;; the amount of patches in between two roads in the x direction
( j6 Y8 B" R( m4 o& ]4 t grid-y-inc ;; the amount of patches in between two roads in the y direction
8 F! f; B& y. B- @2 d( } acceleration ;; the constant that controls how much a car speeds up or slows down by if- D! M O2 m+ k" B
;; it is to accelerate or decelerate
! K7 j9 C0 W! ~/ P; ~% w- S/ \ phase ;; keeps track of the phase
7 v" @- P: \1 e# K# G2 d M( _7 u num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure2 U" Z) M) e0 j* y) k) e9 w0 ]
current-light ;; the currently selected light
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- y" j" G' x' I7 i$ | ;; patch agentsets* L$ f" R5 k. y" F8 N/ D- ?
intersections ;; agentset containing the patches that are intersections
' H: K9 d- {& u( L! M% j roads ;; agentset containing the patches that are roads; ~& V9 g9 r' u# i
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& N# b( M: m( n" K! Tturtles-own' ?5 V" q( g8 o# `' t7 X
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, t# {. p# r3 u3 @4 R speed ;; the speed of the turtle
2 {5 |9 }: w% ? up-car? ;; true if the turtle moves downwards and false if it moves to the right: v8 F& B+ t) z+ g/ _9 o
wait-time ;; the amount of time since the last time a turtle has moved3 d- e0 d+ \, j o: [0 c1 H9 [ i
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patches-own
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" s0 g$ f( ?0 z1 b/ E- i6 h! _3 R intersection? ;; true if the patch is at the intersection of two roads/ H+ B# A% i% x- z# n
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ J, K5 e& a, N; t ;; false for a non-intersection patches.+ z( k1 Z1 M* _, G
my-row ;; the row of the intersection counting from the upper left corner of the! l, r) u& f4 y( Y* R1 q" {0 C
;; world. -1 for non-intersection patches.
) A7 Q- J) H+ P# E9 g' X my-column ;; the column of the intersection counting from the upper left corner of the
4 r' J7 [/ k. D {: ^ ;; world. -1 for non-intersection patches.) x [' V9 e$ T5 |' o6 L
my-phase ;; the phase for the intersection. -1 for non-intersection patches.0 p7 y7 r# e) Q n
auto? ;; whether or not this intersection will switch automatically./ n( L- w- R2 y: T$ k+ {
;; false for non-intersection patches., {# W d, K0 r2 T
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) N8 L: g. p2 q;;;;;;;;;;;;;;;;;;;;;;5 G5 G; D0 }! r& ^
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.* s2 _+ p5 G( C9 F5 g8 v
;; Create num-cars of turtles if there are enough road patches for one turtle to
8 E; ?1 ^. [7 k& };; be created per road patch. Set up the plots.
8 ` [; L* c L9 j; N- j/ Jto setup& R. E: D6 K0 {" c7 l8 u
ca
, ]# g0 O" z0 v1 C* r setup-globals
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+ p- l$ s% w0 w* ] ;; First we ask the patches to draw themselves and set up a few variables$ m3 o, M! H5 \0 G. c3 X
setup-patches
' t( e$ ^. B- i, `6 V2 C- R make-current one-of intersections* F8 e* w" y3 R' {8 ~) R& Q8 E5 g! ?
label-current1 }- k( m& b N3 b$ n9 p5 D) C' n
7 R" N9 k! H! O9 @, D set-default-shape turtles "car"% l" x1 [% S# H! }4 P" ]* U; h
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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 "
; O. Y# D) j0 d t% z/ R. l "road. Either increase the amount of roads "3 p7 x) I8 Z+ h- A( }/ D# h/ @
"by increasing the GRID-SIZE-X or "
. C- O/ \" ^+ b. S "GRID-SIZE-Y sliders, or decrease the "+ ], o/ j3 n9 d- H
"number of cars by lowering the NUMBER slider.\n": F% B) `4 P5 R
"The setup has stopped.")
% V& Y" ^$ f* b, @3 J! n5 i stop( \ V9 q/ r9 n: T$ [. W& ^
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- y4 o* B( n: Q' W) j4 X ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 i( Y, w( m2 i, E$ j3 k' W& n crt num-cars
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" a# a+ X) e. s+ u4 B setup-cars
, Q/ O# O0 G% o& x! {4 U6 r set-car-color5 Z" ~7 O- F0 E3 L$ p; ]
record-data
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7 r( Y3 R5 C. M& N- h: i& v [+ R ;; give the turtles an initial speed
0 R$ {9 b$ X) x6 L S ask turtles [ set-car-speed ] t1 D: r) C9 f8 p
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reset-ticks
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" j0 i8 I/ s7 w/ Q3 r( r;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet8 l+ v# K, j8 Y7 R ?: \2 z% R+ t
set phase 0
6 l. d$ S! P$ X2 c# U! J3 U set num-cars-stopped 00 l( X# d6 L0 Z9 K' \
set grid-x-inc world-width / grid-size-x, m0 U& L5 I7 c& T; e
set grid-y-inc world-height / grid-size-y
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7 P* ~2 I8 T" K* w8 g3 G ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
, l) C+ @8 b6 y: k8 h6 M set acceleration 0.099
* L7 m6 ?7 A& z, m& cend
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+ \" i0 X( P. D& v7 u;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
" q: @5 M. N; C: |5 L8 }4 `. W;; and initialize the traffic lights to one setting
) U% F' @ }8 V6 Rto setup-patches/ r) C, |& _ S' n+ i& w
;; initialize the patch-owned variables and color the patches to a base-color
% F2 g- K, t& d! s: r8 Y# u4 e( i ask patches
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set intersection? false, D0 _' @+ n+ r. \! u1 w
set auto? false2 A* }0 i3 b( ] Z/ \
set green-light-up? true
* P0 ^. |# R1 b3 D set my-row -1* s8 M% G8 ]5 s: E5 N
set my-column -11 Q) e0 X1 K7 G* D/ ^
set my-phase -13 i4 f. A% s" P7 W! z1 ^
set pcolor brown + 3
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6 P( I8 Y" N/ u6 `) {
;; initialize the global variables that hold patch agentsets
( Z" n% @* ` J" i' `8 G set roads patches with
8 r2 X# o5 |; y. |& A ^) v [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or9 d. A7 M. B; w( m* Z/ @8 g
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% O! k* i& v8 d; F1 y
set intersections roads with
8 q1 S& A: Z3 B! f [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 L# `. K0 M) y$ \' C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ A/ s/ Y- W$ l+ z, u7 c
* a3 z# V. d! U# b ask roads [ set pcolor white ]& G8 Q6 r6 q( z x
setup-intersections. g' m5 O& Z) D' O) E
end
3 x9 l$ B% p+ i1 [7 b其中定义道路的句子,如下所示,是什么意思啊?' T: I( `6 G% d/ m% e! Q
set roads patches with* Q% @8 K& |: p/ Q. s2 w0 X3 E
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or6 n! Y4 @5 ?# Q4 ]9 E! z7 `
(floor((pycor + max-pycor) mod grid-y-inc) = 0)], ~5 G9 }# j4 t, t% ]% j 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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