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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。
) S# m2 I6 V/ `2 g }" o; ^& rnetlogo自带的social science--traffic grid这一例子当中,. \8 g- ]4 {6 M% h# y
globals3 y5 p% |, v+ E, W& ]* Z' f& a
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/ [* c1 Z1 [& v0 y grid-x-inc ;; the amount of patches in between two roads in the x direction" s; }8 o& h. m5 G
grid-y-inc ;; the amount of patches in between two roads in the y direction
( J! j) f' {/ l6 _: g3 _ acceleration ;; the constant that controls how much a car speeds up or slows down by if
! v6 q' J" J) Y( X4 W9 ~# a ;; it is to accelerate or decelerate! Q5 r! ], M" Z4 s$ A
phase ;; keeps track of the phase
$ r/ @5 _1 h0 c. J num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# `" x, w9 s }8 Z! l current-light ;; the currently selected light3 B3 F5 W( f9 @5 A
2 ^8 J3 S! _$ n+ k) z; o ;; patch agentsets
9 [4 Z7 z. g9 y5 j4 ?" G intersections ;; agentset containing the patches that are intersections
, K8 g% m1 x' _0 g roads ;; agentset containing the patches that are roads
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turtles-own, D! `2 ^# b( K; W/ p C
[
: B! i+ `& P! h) s# [ speed ;; the speed of the turtle
( W. ]4 y% M! x1 x) q: u up-car? ;; true if the turtle moves downwards and false if it moves to the right8 d: I+ p& u; b0 Q3 `3 Q
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads* ]! ?# F, H8 U2 F/ c6 X, v) t. u
green-light-up? ;; true if the green light is above the intersection. otherwise, false.* J5 e2 _+ {) j+ m
;; false for a non-intersection patches.0 d2 r( Y/ W% o- J
my-row ;; the row of the intersection counting from the upper left corner of the
2 m9 g: ?8 Y8 F* H( P2 v9 ?- l$ e# n ;; world. -1 for non-intersection patches.
; A( z* `; L4 Q$ P' X) ? my-column ;; the column of the intersection counting from the upper left corner of the
* n+ H& C/ @1 z+ n9 E ;; world. -1 for non-intersection patches." j3 x6 p" W+ |6 a2 R% r, F6 [
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
- d- m; ^! ^1 R8 X l# a q auto? ;; whether or not this intersection will switch automatically.
# o( b; {6 \9 N. Q3 x8 u ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
3 a" R" B/ }( _1 b ^! l: ~" n# |;; Setup Procedures ;;% P: ~; }0 D* [ T: u" C+ y6 a: r' K
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.$ J& ~5 n9 e1 P1 h' {2 B
;; Create num-cars of turtles if there are enough road patches for one turtle to
; c! `: [ M1 q: |! ~/ X;; be created per road patch. Set up the plots.% D1 _5 A/ o& t0 h' S- H
to setup; f9 I" @0 h1 ?. ], Z
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setup-globals$ ?1 i' \/ ]/ A ^1 d
4 j9 h, v0 B) `% F) z, K3 S ;; First we ask the patches to draw themselves and set up a few variables
1 q6 F; h8 c' N. g setup-patches
3 J8 i; Y: q C) x$ y7 Z make-current one-of intersections
- m: X" G3 y/ t* W label-current/ K N! X% Q$ [2 _4 |- a! J
0 _ \& N' K$ a# ^/ }2 C y set-default-shape turtles "car"
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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 ": r. A* L9 {9 R# f5 F X. Q* P
"road. Either increase the amount of roads "
4 c$ ~# ]2 M }+ p8 q: ] "by increasing the GRID-SIZE-X or "& _" K! P) {2 L2 b/ _
"GRID-SIZE-Y sliders, or decrease the "8 _2 W R5 T7 w0 M7 U; d3 n8 T3 C) V
"number of cars by lowering the NUMBER slider.\n"0 l/ ?2 ], t# m# F# p d6 | v
"The setup has stopped.")
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
. g6 C$ p3 r7 N, g$ l3 h* _ crt num-cars( v) a+ Y9 ?: p5 s |
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) ~/ R5 @2 K- f% N setup-cars
; C- O K" \; o8 G$ k& N: B; N set-car-color3 R! [. C% b8 m6 C' {
record-data! K( z0 s3 @" a# j+ i( X
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;; give the turtles an initial speed5 v. |) L( ~" b0 ?
ask turtles [ set-car-speed ]. E7 a9 c* U" \
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reset-ticks
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;; Initialize the global variables to appropriate values
4 {( X! V- h$ O) Bto setup-globals
5 G% @& {" y: C/ N) @ r, b: t set current-light nobody ;; just for now, since there are no lights yet
; ~7 K1 d- L) h* g4 e- c' z set phase 01 S- f- i, u) _- [$ b
set num-cars-stopped 0. T, x2 |* G F3 W
set grid-x-inc world-width / grid-size-x M8 H- J x7 i- h0 _# d
set grid-y-inc world-height / grid-size-y- @3 ]) i8 e, z6 p
$ M) q! S6 y _7 X7 @4 F6 o ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary& l3 L$ H( @5 j/ v1 m1 W# J, ~9 ~
set acceleration 0.099
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2 S6 B; z7 P/ \, N' e( |. u;; Make the patches have appropriate colors, set up the roads and intersections agentsets,4 B/ X2 Y7 J; f( |) z$ {, F
;; and initialize the traffic lights to one setting% d( i* P+ A8 `" ~' W" i# r2 n' U
to setup-patches
4 u \$ |% i9 D ;; initialize the patch-owned variables and color the patches to a base-color/ d7 m5 v; `. N- j% | P. C% k
ask patches9 ?) g2 u7 ?! u, n
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$ e0 K1 T Z# i, i' C4 c, K {$ R set intersection? false
8 u/ g) H, n3 f9 Q1 @ set auto? false
: B3 A% L% z8 B8 f set green-light-up? true
5 A( _, q, s* l8 H0 V set my-row -1; S5 T3 O/ i- M. |1 q9 N
set my-column -1
# W5 Q3 Z. h3 i2 i) b d4 [ set my-phase -19 M' |" @& k# a6 [3 w3 G" v& _8 O% ^0 G) y
set pcolor brown + 3( Z+ _9 t- j$ w- T1 i
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;; initialize the global variables that hold patch agentsets
9 D" H6 ^3 q: C0 A6 Y; k set roads patches with$ h/ g. ]- j+ E, C2 w$ u
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" s' n7 t" Z/ y8 P2 h (floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ l' v* V8 v; f
set intersections roads with
; S% y4 H3 {) Z9 d/ d0 C8 H$ C [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
0 h6 d6 t5 r% K# ` K0 ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; `7 P: K2 k c2 k2 K- g% U
: u0 }, n& I# B' j* h ask roads [ set pcolor white ]3 ?- v; q+ M7 G& L* m) p+ r- z+ a& d
setup-intersections4 {- Z( u! A, q, P
end
. K2 {: t$ [3 E9 a( o其中定义道路的句子,如下所示,是什么意思啊?4 O* J$ }3 q. U
set roads patches with; F" d7 q8 l& T% w
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; m$ x$ E* P8 u2 n e' c' w4 b
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
@# @: c* h) H: G9 _/ P) b4 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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