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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。8 Q: J+ [' h/ q( N( [3 f
netlogo自带的social science--traffic grid这一例子当中,
0 d1 ^2 w) w2 E1 H' f8 K( Tglobals8 P9 E- N; J! X" q" ^! B
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/ Z# e( j9 ?5 i7 a grid-x-inc ;; the amount of patches in between two roads in the x direction- ~( ?/ ]' |5 T3 F! N% b) v/ r
grid-y-inc ;; the amount of patches in between two roads in the y direction
; i$ n4 x. n7 \& H* R acceleration ;; the constant that controls how much a car speeds up or slows down by if
8 J0 `$ t2 H. ?" I ;; it is to accelerate or decelerate
' K* G1 v5 i! z0 E8 S phase ;; keeps track of the phase
2 d9 _# Z* n j+ G* }$ m num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure7 z& n- ~+ c2 { W- D$ Y# E
current-light ;; the currently selected light# _# J$ ?# W) m% D/ F9 l" k, o
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;; patch agentsets9 Z& q& E0 a7 Q" r$ D- P- I, z
intersections ;; agentset containing the patches that are intersections) |' N1 ?: \9 Y, E ~) c5 @
roads ;; agentset containing the patches that are roads
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! `- k0 I; n. X- X$ X- hturtles-own5 z7 u1 l( e- b$ h% ` H3 i
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speed ;; the speed of the turtle
7 Y, E4 ~1 ]3 ?. C1 S& N up-car? ;; true if the turtle moves downwards and false if it moves to the right
* a n6 Y7 m6 h) m" @0 O wait-time ;; the amount of time since the last time a turtle has moved/ d/ d* J: E4 L. K
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patches-own
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3 H" R/ K7 ^1 v* F* d' l intersection? ;; true if the patch is at the intersection of two roads, v; H6 x$ w8 b& ?% ]
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
( T* k1 B+ f9 n( p% a# h ;; false for a non-intersection patches.& F9 w( n" F( g7 A. w
my-row ;; the row of the intersection counting from the upper left corner of the8 L( M& ^/ H$ _& k% q: d5 r- C) |
;; world. -1 for non-intersection patches.; N! @5 u7 j; Z6 k+ W3 {
my-column ;; the column of the intersection counting from the upper left corner of the
0 I! a. p; Y! S( w1 [. o ;; world. -1 for non-intersection patches.% s* g9 h1 F& q* o7 H
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
0 t/ x: c3 {" H) _) N5 b auto? ;; whether or not this intersection will switch automatically.
# K0 O4 [; ]7 U/ I' x ;; false for non-intersection patches.6 o. t1 e4 i J
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;;;;;;;;;;;;;;;;;;;;;;
; B. Z9 A5 i" X0 I;; Setup Procedures ;;* A" q- M J6 t5 j( w5 w1 _
;;;;;;;;;;;;;;;;;;;;;;+ `2 E% W5 F# r
" U$ L' c* K8 g) _) V3 t;; Initialize the display by giving the global and patch variables initial values.2 a: C) r9 Q+ o6 u; {
;; Create num-cars of turtles if there are enough road patches for one turtle to
6 @, t! Q! R# G1 ~2 F;; be created per road patch. Set up the plots.
5 Q1 f5 U3 O' N+ ^& `to setup* g4 v+ _1 l! @! J+ T
ca
R% c& d6 z; v$ ]! K0 {: L' g setup-globals6 k4 x7 b& M* s3 J9 I
1 m3 b4 r* [. B$ {) o ;; First we ask the patches to draw themselves and set up a few variables8 k. G& s0 R+ s# Z0 ^! M
setup-patches) \) Y, X$ y3 U0 b( f" i! N ]
make-current one-of intersections, ]$ C v( g8 ]5 z- S; h) r5 ~* G) j
label-current
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set-default-shape turtles "car"7 Y$ r. d# T! g
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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 "
! e9 U2 U) e( K9 v9 K. m2 J. Q "road. Either increase the amount of roads "
3 p5 g( b* }" H% `( F7 I "by increasing the GRID-SIZE-X or "9 ?8 G2 t% A& x9 p1 s9 O# n
"GRID-SIZE-Y sliders, or decrease the "" |9 o5 W+ i2 |4 w( S0 V- e; t9 n# H
"number of cars by lowering the NUMBER slider.\n"; u1 } y! e' I& [5 |2 M2 R& B
"The setup has stopped.")
( {) }! V) a! _% M5 o stop# v9 g# W5 f6 w8 V" ~. P# I
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, d9 j( K2 k2 X- V$ C( ~6 \
crt num-cars
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5 M9 _$ l* b4 Y( D+ L: O9 H5 S: ~ r setup-cars
8 ]3 V( L: T. C7 j; G- ~( T set-car-color
/ `% S2 E: }" p- B4 k+ p, g record-data
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2 P0 r. G3 l) l8 E2 g* r. i ;; give the turtles an initial speed
* u6 B* Q' a) W9 E" V A$ p/ T7 | ask turtles [ set-car-speed ]
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" I2 d' r' z! `! ^( ~( q/ R reset-ticks! d' `( o: Q7 l: f
end
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) U7 Q2 u! k } q" k1 d2 g5 u: ?$ U;; Initialize the global variables to appropriate values
2 X; a" j' q- ]2 gto setup-globals6 \0 y( M0 o% _5 w- r8 d
set current-light nobody ;; just for now, since there are no lights yet
/ T- ]7 b R% t% [+ X2 n- c set phase 06 o/ R$ O9 k' L! g0 z: }
set num-cars-stopped 0
/ X/ J$ x2 G" s& E. c0 K) J8 F8 ` set grid-x-inc world-width / grid-size-x; J, d( v! F6 E/ Q- l' k; f3 |
set grid-y-inc world-height / grid-size-y
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* C/ T; A+ h# ?+ I* Y" s ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: K. x" ?8 U. Y6 _: s+ F
set acceleration 0.099& w$ n t1 M; t& e
end! h* @4 i7 ]/ X5 g
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets, u8 `" D( R7 |2 m9 D3 N. O" Y
;; and initialize the traffic lights to one setting( x5 }& N% g0 C0 K
to setup-patches7 E$ W% V3 ?* d( E8 {+ T
;; initialize the patch-owned variables and color the patches to a base-color
! n% f" r8 v$ D$ \2 T) z6 A9 i ask patches
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6 ~ I- U( V! w* J# f; a set intersection? false
5 V* T$ X: @0 k) w/ ^) T6 w' J2 F; [ set auto? false
' W& X$ U) W! I; e! N set green-light-up? true: f Y7 z+ v2 L8 ^; E# c
set my-row -12 r# M& i: i+ m4 W% }0 p
set my-column -1
/ |9 T# X, V _( Z& u set my-phase -1
]6 t. ^9 W4 q set pcolor brown + 3" |# Y# \' ]; s4 T# ?* U( c
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;; initialize the global variables that hold patch agentsets# f( r3 t* i; M
set roads patches with
3 g O# f$ K" y3 J* ? [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ B i+ \( V) z, U ]- k; L" } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
v2 E7 t% h2 m/ ~ set intersections roads with
9 e3 D* |( q8 F% B1 f [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
7 D1 G# p* D5 O0 x m) a2 S6 Q& I (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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- q, @, L! F& r, l& S% S ask roads [ set pcolor white ]
( ~$ D' v8 z# ]$ |0 _3 j0 e setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?! `+ b2 S9 t+ L$ B7 l3 [2 {" y
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 ]& V3 y- R; H- h% |% H
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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