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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。
6 {4 e, d8 c' [) cnetlogo自带的social science--traffic grid这一例子当中,% ~* E8 x' j, K$ h) H
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction# c( W) z5 O* H1 q6 ^
grid-y-inc ;; the amount of patches in between two roads in the y direction
0 h# `' T$ |1 V# Y$ d/ ?6 n, V acceleration ;; the constant that controls how much a car speeds up or slows down by if8 @2 p: P! X7 s: P; ]5 ]( c1 R
;; it is to accelerate or decelerate$ H; M$ Q Z3 k* W0 ]: T
phase ;; keeps track of the phase
1 p8 k9 ~; H* ?8 B7 t+ I+ } num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure! J' U+ B, v1 x
current-light ;; the currently selected light3 F: G: H1 {! x% O6 r+ h Q
" p9 n/ }0 {, D. T% m8 f ;; patch agentsets: a( g6 i& e% X
intersections ;; agentset containing the patches that are intersections" H1 f8 U7 b+ ~
roads ;; agentset containing the patches that are roads; V/ R8 i2 q1 Z8 ?
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( M( G# W+ S+ H$ Jturtles-own5 [$ G7 g* e+ L2 f- D n1 i. W
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( j6 ^8 V6 _: I speed ;; the speed of the turtle) h$ e* V: C8 l1 W
up-car? ;; true if the turtle moves downwards and false if it moves to the right
5 a5 Z7 h# w. g wait-time ;; the amount of time since the last time a turtle has moved$ L: ~ G; a2 n B% Y2 a8 z
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patches-own p2 [2 _4 l6 Z, \& H! R( l
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! ?' k# |& T* [; F: [8 I' S intersection? ;; true if the patch is at the intersection of two roads
G8 x( d$ R, U6 A2 c green-light-up? ;; true if the green light is above the intersection. otherwise, false.6 f/ t* u' n m m# s% b
;; false for a non-intersection patches.- k1 Q" ]6 k5 z+ ^9 V) u A
my-row ;; the row of the intersection counting from the upper left corner of the
) q" A( j( h4 U, l( z8 x/ _" ]: X4 j ;; world. -1 for non-intersection patches.
9 n7 f% r1 {7 ]# b% P( L my-column ;; the column of the intersection counting from the upper left corner of the
: K) b% s% |% r9 R) q: j$ t6 \ ;; world. -1 for non-intersection patches.
, w% X9 Q0 s" w' ?$ f1 L my-phase ;; the phase for the intersection. -1 for non-intersection patches.
( {! W# L4 N! \4 k8 N auto? ;; whether or not this intersection will switch automatically.
4 ^6 w7 v$ u- G2 S% c$ ? ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;; L! c9 l/ o( s. c
;; Setup Procedures ;;* H9 H7 r R6 ^4 g* t( e
;;;;;;;;;;;;;;;;;;;;;;
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8 b4 @; j. r, u* f$ C;; Initialize the display by giving the global and patch variables initial values.
% J7 I4 o9 _) n9 r* H$ E;; Create num-cars of turtles if there are enough road patches for one turtle to
: }6 \: ?3 t& n6 {; F;; be created per road patch. Set up the plots.$ A" J- f& ~; W& J
to setup
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7 S. ^, {& D1 K# x" M0 H setup-globals2 @& |% |0 |8 z* [) g5 H
% X8 C& R2 k3 P" y4 w6 q/ E9 { ;; First we ask the patches to draw themselves and set up a few variables
; T q4 c0 t- K5 x/ W4 @ setup-patches
# S: z, I, C/ }. j make-current one-of intersections* a# k% n. E4 j' v9 Q. Y
label-current2 S' b+ p1 A5 ~
1 v" e5 G% T5 l# U6 D set-default-shape turtles "car"
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if (num-cars > count roads); v# R- z/ s, W, U! ]& |& S k
[
r) U# Z% h# s) k" U8 { user-message (word "There are too many cars for the amount of " |# z W, T% a
"road. Either increase the amount of roads "
1 T/ b6 q) S+ o "by increasing the GRID-SIZE-X or "
! D+ a8 e. F4 C "GRID-SIZE-Y sliders, or decrease the "0 ]% i* e% s- H& Z
"number of cars by lowering the NUMBER slider.\n"
$ _, `3 g1 l; F# r0 K "The setup has stopped.")3 c2 Q$ G3 N! I
stop' k( r& l; {- u) v% j9 }
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% T1 Q9 E8 L) y7 s/ D ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
+ B7 n! Y, A0 x8 @" T+ K8 k+ b" C crt num-cars
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setup-cars
9 F/ e1 j/ r1 L- ` set-car-color
% y+ _7 }4 V/ ? record-data$ ]7 d4 S. I J+ u
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# E( F0 E8 K! c ;; give the turtles an initial speed1 ~6 V& h8 k3 |2 h8 D! H$ b+ x# W
ask turtles [ set-car-speed ]
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% D- m0 F+ _9 r' C reset-ticks
) t+ e6 A& j- |$ z4 T3 M, Y1 Uend
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# w7 \3 N& x( V0 Z& t4 _;; Initialize the global variables to appropriate values! t- @# L/ |. G9 t7 G
to setup-globals( `( A: X, j: d; S
set current-light nobody ;; just for now, since there are no lights yet
( B1 G9 T9 p$ r5 ^9 O$ y* l+ Y set phase 0+ `$ C. |8 b/ d: k
set num-cars-stopped 0
1 c# U& H. e* _$ R1 i set grid-x-inc world-width / grid-size-x( X0 y F; g9 e) O. H, \6 Y
set grid-y-inc world-height / grid-size-y+ ]( _ ^5 N2 n: w
. G* ^8 ]$ K! U ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary8 S6 ~" R- L+ E3 @( g
set acceleration 0.099: P# z8 n- `/ e* Z. q. J
end% f6 M" U. h2 V: E! n
9 Y% R) D* L! L3 Q" G: O;; Make the patches have appropriate colors, set up the roads and intersections agentsets,* m3 P! O5 a& j& N
;; and initialize the traffic lights to one setting
7 Q1 U7 q+ S( _to setup-patches
( a3 B- ]! o. B) Y& I8 K8 s ;; initialize the patch-owned variables and color the patches to a base-color
! s1 w. A. K: k) ^: J7 y ask patches
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+ Z" ?/ z0 v. z6 |/ G. M$ i% u" H set intersection? false, R! m% \/ W/ G1 D7 p) D
set auto? false7 y7 @0 }: ?) z: ^ h% q: T! ?' {
set green-light-up? true p/ ?3 z, ~) l% T8 d2 P
set my-row -1, c' W: b1 L' I: J
set my-column -1 _! G; i, i% K+ S% d+ Y
set my-phase -1/ W3 i T! ], ?4 v4 V
set pcolor brown + 3
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% i2 s. V6 }4 P' N% [) X( l4 f ;; initialize the global variables that hold patch agentsets
" z' n5 r' m% N1 V8 |4 Y set roads patches with
& `8 K- o( N- l' q w% h% O# Z" k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 i( c2 g# g4 V9 D! @+ x: P
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 y8 k4 D3 P$ b2 j
set intersections roads with( I, l3 \8 F, D
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and: j5 }9 s+ S% i1 C. @; j$ X/ [
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% ~3 `$ i. E( ~ R( c, l# ]( @3 ~
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ask roads [ set pcolor white ]7 B9 _% s* s, N5 w' u
setup-intersections. b# ?# i) D% f6 w
end, {9 E7 g# _+ d* S. l4 D% j, t6 E
其中定义道路的句子,如下所示,是什么意思啊?& `/ n5 d) U; W$ ?6 {: ^
set roads patches with$ E5 t. a0 r6 c) u0 a" ]! m
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 R ^, i/ \6 g0 W8 X1 Z0 z6 S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 Q, o9 n) l0 P9 Y7 i* 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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