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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。
! ?2 Y, F6 X6 L+ b- @4 o' Z/ Znetlogo自带的social science--traffic grid这一例子当中,
2 R' s* H+ N$ Lglobals
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d/ {' \% l/ a& J: j4 h1 b grid-x-inc ;; the amount of patches in between two roads in the x direction: o- H. R8 v0 K
grid-y-inc ;; the amount of patches in between two roads in the y direction
3 f) u+ z( ^! q) a8 H/ U1 E acceleration ;; the constant that controls how much a car speeds up or slows down by if
) z( a* K$ r4 p& Z ;; it is to accelerate or decelerate
% n/ E: i6 e! c/ c2 u2 t8 W9 \ phase ;; keeps track of the phase3 Z0 j$ k' U2 ], w) ~& q
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure3 J' U6 Y6 z+ f. Y# j! k
current-light ;; the currently selected light8 N7 h: J! Z$ p4 J
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;; patch agentsets; ?. }( [* ^- ?- z: W
intersections ;; agentset containing the patches that are intersections
( V. ^8 F4 H6 M: i8 g( I$ ? ? roads ;; agentset containing the patches that are roads# d8 m% F$ x) i9 a/ Q( A6 O2 z6 o
]
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, P' e' ?* w0 p! @. Y7 g) k' wturtles-own
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. A5 U# e/ ]+ i speed ;; the speed of the turtle0 i* Y# M1 L/ n' H; J: ~! I- ]- i
up-car? ;; true if the turtle moves downwards and false if it moves to the right
8 l7 a9 Q, `' U2 a wait-time ;; the amount of time since the last time a turtle has moved
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0 s* v e3 q& `+ n$ b- ipatches-own
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! ?; l$ I) o0 K6 g: E4 I3 N) _ intersection? ;; true if the patch is at the intersection of two roads8 S: b+ k+ i: F6 b' a4 O
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
+ F/ n, H0 t) w" L ;; false for a non-intersection patches.1 n! Q7 S! |( x0 Z! P
my-row ;; the row of the intersection counting from the upper left corner of the
& Z' T! S- [# m3 H P4 J* G ;; world. -1 for non-intersection patches.2 h; T( @5 ?/ t2 \7 |- r' V3 g
my-column ;; the column of the intersection counting from the upper left corner of the4 D0 X; B. j& [, ` J3 |* A2 o
;; world. -1 for non-intersection patches.
" }9 y! P' q8 T9 C2 B my-phase ;; the phase for the intersection. -1 for non-intersection patches.. I1 c0 g2 \3 j1 E7 `$ M: m# `1 o
auto? ;; whether or not this intersection will switch automatically.5 L: o1 F& e) O! G% o; Z
;; false for non-intersection patches.5 I: ^1 }. t% e# R5 S
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% y P/ a0 l9 W4 j9 w$ G \;;;;;;;;;;;;;;;;;;;;;;
' B% k3 O; ?4 b( \! F;; Setup Procedures ;;
# t. y k( N& i [, C s# ^* \- \;;;;;;;;;;;;;;;;;;;;;;
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8 E" d! J9 `9 Z- j [;; Initialize the display by giving the global and patch variables initial values.
0 C$ I. e: ]# @! M+ p;; Create num-cars of turtles if there are enough road patches for one turtle to6 v: V- c& _4 K
;; be created per road patch. Set up the plots.- n" @" h/ D9 A# z! r: I; x
to setup" X7 P0 q( M- ?
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setup-globals: Q6 _: r7 k/ D" D K
# Z. u& p1 X% C5 t3 I* i y; F ;; First we ask the patches to draw themselves and set up a few variables
* O' @2 a' a$ b4 M& n setup-patches
" l4 T4 C7 i- {3 M/ D make-current one-of intersections- W7 Z. X) o8 ~9 v/ g) b
label-current
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& y' n: {! ]. Q. T! D. D6 T* Z set-default-shape turtles "car"
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' C- d" [# i- h6 S if (num-cars > count roads)" A# U8 D9 P* O( a5 f' s+ v u
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user-message (word "There are too many cars for the amount of "
" k6 S! ~6 D3 i8 e) w" o& n- |! a: o1 A "road. Either increase the amount of roads "7 ]0 F4 f' }2 {. Z2 E
"by increasing the GRID-SIZE-X or ". b: [; V* K/ A3 T
"GRID-SIZE-Y sliders, or decrease the "
0 z" x" P, J1 P4 s "number of cars by lowering the NUMBER slider.\n"
$ M) f. k H; {6 t V. \ "The setup has stopped."): ?- E. Z) A; E1 v) v! T
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 m6 @! u% q0 z$ s$ ?/ b# X3 @ crt num-cars. V' r/ o- J/ b6 [/ p
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) E6 W8 Z6 J6 Q2 e$ o, S& r setup-cars
% g* E9 B8 M4 ~* x set-car-color4 q1 a/ s- z9 V$ D2 C
record-data
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;; give the turtles an initial speed" m9 f$ i$ S7 E& R! g9 f
ask turtles [ set-car-speed ]
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. w* u+ b# u) P& ` reset-ticks
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;; Initialize the global variables to appropriate values
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: [: b& ^9 z3 w, }2 w- b! ] set current-light nobody ;; just for now, since there are no lights yet) n @( x; }7 d- l6 `
set phase 0
) i3 u j0 D/ }2 c6 D E set num-cars-stopped 0 x, I0 L( C4 Q. p
set grid-x-inc world-width / grid-size-x: h* g' D, O. Y# C" c9 _0 T# Q
set grid-y-inc world-height / grid-size-y
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3 p0 d. y1 r2 P7 \0 F0 o, P' t ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary( E" m! A; p' y5 s6 R
set acceleration 0.099
& ~! Z2 v; V N0 D# g) Xend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
( R) T7 H& U$ e;; and initialize the traffic lights to one setting) K2 b* @, P$ g" n! Y1 @) S7 J
to setup-patches
, v2 ~: \! A- T2 a, v6 u ;; initialize the patch-owned variables and color the patches to a base-color
* \: A0 H7 v) B$ }# v; [ ask patches
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% `0 D4 l' q/ ~% ~! h$ r set intersection? false5 |4 G6 e0 D6 g9 J1 _, d
set auto? false
P2 \3 S0 ]# w5 z u! p; O1 ` set green-light-up? true" E/ }' H; }+ n, J' y
set my-row -1
2 z% L9 q8 w. ~" I set my-column -14 A: k& }$ p1 D3 K
set my-phase -1
0 l( ^8 V: W! G% }$ y set pcolor brown + 3- C0 y7 `6 U& _6 i X T
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;; initialize the global variables that hold patch agentsets/ ]9 U" n: H0 F
set roads patches with
5 i' ~$ }# |- ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 ^. |0 Z% R" y, Y# p0 _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% c. a$ G3 g8 V% B- V
set intersections roads with
8 Q; r5 r6 ^# K- W' F [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and7 a+ k* z5 t0 p# }8 `3 @4 b
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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8 l* d7 o( s4 c2 l" F3 d; k ask roads [ set pcolor white ]
# t- t2 n' p( A' T% O4 N/ s% ? setup-intersections
6 c) W2 c9 s4 K" ?end
6 M9 |" E7 o/ v4 r其中定义道路的句子,如下所示,是什么意思啊?9 _! k6 x r' U5 k$ u% T& P
set roads patches with) _+ Y" Z$ [; ^. l
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or ?9 a( o2 _! e5 i& [" }" v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ f3 ~; r$ \# E! e4 I
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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