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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。# a; t9 F3 s: c- h! w/ G x- u
netlogo自带的social science--traffic grid这一例子当中,
/ L* Y( J/ E2 Z3 Y2 Q' B1 p% l) `globals. Z& E3 i, \& o& A
[
: P" H" F- ]- [ grid-x-inc ;; the amount of patches in between two roads in the x direction
$ D( p- s6 H3 ~8 m grid-y-inc ;; the amount of patches in between two roads in the y direction: J# t$ U) |, u2 a/ R
acceleration ;; the constant that controls how much a car speeds up or slows down by if
) |# C F$ s+ |( y5 d ;; it is to accelerate or decelerate
3 M! V; I5 E M+ x phase ;; keeps track of the phase: _9 o1 R6 p/ b1 x, t8 o. W. ]
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
: W3 v! W! W9 a2 ~ current-light ;; the currently selected light; ^4 R, ~# T9 x- ~ \1 o
7 x" g7 L0 n" w. U ;; patch agentsets5 ~0 G L* \+ @) e& q# v
intersections ;; agentset containing the patches that are intersections- s0 }7 C+ @/ m# |' K
roads ;; agentset containing the patches that are roads) K5 {0 ^) L* z8 {4 {
]
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" C. `, b0 G: U. g# l$ _turtles-own5 i6 ^1 [3 ]" b
[
+ y3 E( R u2 t p$ A7 V- _ speed ;; the speed of the turtle
3 r: |* X- ~0 Y f( S up-car? ;; true if the turtle moves downwards and false if it moves to the right$ a$ D, ^ \( Z" e+ o( \) P
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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$ i: m0 e8 K1 H2 L3 c intersection? ;; true if the patch is at the intersection of two roads
0 Q3 O, w9 C5 I. ?4 i6 j green-light-up? ;; true if the green light is above the intersection. otherwise, false.( q$ f/ Z _7 l1 G
;; false for a non-intersection patches.7 N5 E/ J8 V* X& D9 e
my-row ;; the row of the intersection counting from the upper left corner of the$ G1 z2 i9 T2 V% V% s& {9 y' ]
;; world. -1 for non-intersection patches.: y% B1 o! q4 y& W- E! z! T/ O
my-column ;; the column of the intersection counting from the upper left corner of the" f/ l0 @" {3 l% g( x: H: n0 L9 E1 N
;; world. -1 for non-intersection patches./ O; z! h. `1 p, y3 h
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
3 N7 l4 u( A" Q; B auto? ;; whether or not this intersection will switch automatically.
3 X/ ?2 {0 c5 D+ k6 t ;; false for non-intersection patches.& p0 ?) `8 a$ e; `1 D+ n* o
]
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1 ^! g' z6 F6 n;;;;;;;;;;;;;;;;;;;;;;2 v# V7 L, ]9 {1 A
;; Setup Procedures ;;* J7 z4 k9 K' }( d$ w- d5 Y
;;;;;;;;;;;;;;;;;;;;;;
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1 L' ?, M6 G0 F3 w: K& ^;; Initialize the display by giving the global and patch variables initial values.
; d6 e1 x3 S$ r3 h;; Create num-cars of turtles if there are enough road patches for one turtle to9 \5 [2 C' h8 b. T, a k. t0 y; m. j, A
;; be created per road patch. Set up the plots.
% j1 b5 L, E8 ]. t% f9 c# Wto setup
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3 @ V9 l" b7 K$ c' t3 x8 O% d setup-globals/ ?5 m8 r% M( M; n* l
( [4 Y5 v. _2 w9 i. | ;; First we ask the patches to draw themselves and set up a few variables
; l* T+ v+ n+ ?# r9 O setup-patches
, |# {4 O6 g/ k' }2 l7 f+ t8 M make-current one-of intersections
" i! z6 n9 k" l5 h9 b: ~ label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)" ^$ d0 g5 L5 H. |8 |- y
[! U* m$ E. D1 u3 \* [3 \
user-message (word "There are too many cars for the amount of "- v- D' T7 ]! y1 U
"road. Either increase the amount of roads "/ g3 b* u4 I \
"by increasing the GRID-SIZE-X or "
$ r) }4 w n$ T2 `- i) m2 E "GRID-SIZE-Y sliders, or decrease the "
+ O) U4 n. u3 @+ W$ t7 O; M6 H "number of cars by lowering the NUMBER slider.\n"8 ?5 M8 T8 C+ q. D# m, v
"The setup has stopped.")
7 f2 |, d4 P- j* Q6 F F stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color4 D, e3 S6 D0 e7 K' [; }
crt num-cars7 i; H- r; O2 O: t4 @
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/ g) R7 z4 w8 @8 @" a' {6 a1 Y' F setup-cars! K5 r& M5 T, j* o9 S! t* ^' j
set-car-color
) a: R; S6 }. y0 n' q, g6 I record-data# D" ~( G. O+ V6 X5 `
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; n7 q; Q6 T2 g& M* E) O' D0 I$ j ;; give the turtles an initial speed
4 i2 {9 h5 d: Y1 g' Y! ] ask turtles [ set-car-speed ]
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reset-ticks; n4 `5 M. _. }; o4 h7 L
end
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1 w8 f. v% u8 E( g3 ^. p2 E) O# ^;; Initialize the global variables to appropriate values) K* Y5 O# l: \! R# y3 o
to setup-globals3 w1 G0 J9 t* A5 O8 r+ H
set current-light nobody ;; just for now, since there are no lights yet2 C4 y5 @; @; z/ h" c7 _
set phase 0
" |" n+ R8 l; f) Y; d set num-cars-stopped 0
7 [. X/ j: x) E4 ] set grid-x-inc world-width / grid-size-x" k: x+ } H$ y" P9 T) R
set grid-y-inc world-height / grid-size-y* Y: d7 i9 \" \- a2 g$ K5 ^4 f
8 J* J/ O! t2 z ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary |: i0 g% ?& w
set acceleration 0.0997 {6 u# b q/ ^$ f9 c! q
end
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7 q8 k& X9 X) d% X: w;; Make the patches have appropriate colors, set up the roads and intersections agentsets,$ n o5 k" F2 e' u$ L
;; and initialize the traffic lights to one setting J$ w$ h6 ?. G) h, G: ^2 A' h
to setup-patches
: {9 Y# |* h# ~6 e0 q, b1 G& o0 S ;; initialize the patch-owned variables and color the patches to a base-color2 a' w' k4 E" h( R; J: }
ask patches
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: \5 m6 H. {- l set intersection? false
; a( V. x& d" B+ M5 S set auto? false7 p* L: M+ l" M9 P! M) B
set green-light-up? true( ]) j4 p) A) ^' b$ m
set my-row -1 I V" w6 x* o" M. p- h3 q4 a r
set my-column -1# N+ [. p3 g1 s: x b# e
set my-phase -17 N* _* A! O; K7 l; G) y8 D
set pcolor brown + 3$ @2 O& g0 T. u: p% e1 U7 ~3 |
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;; initialize the global variables that hold patch agentsets: v/ t e6 w, p. J4 u7 b1 D3 h! r
set roads patches with
8 a8 i' Y/ E1 A# p6 ~! z/ M# { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 ?2 j, D) c8 L- f. S" b t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 r, G! b3 J' w# b$ V0 j
set intersections roads with
) a2 ]: P: U( J [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and1 E, m- g, \" \* n8 z1 P$ ~$ F0 W2 ~
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]" m B) W' a* N* [
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ask roads [ set pcolor white ]
3 Z. S" ~' j! H# O setup-intersections7 P6 Q2 h' I$ ~" C
end
+ n- o5 u6 u8 ~; x+ ~其中定义道路的句子,如下所示,是什么意思啊?2 b* w8 I6 \ T- e E5 x+ a+ y
set roads patches with
; p0 P, _5 X$ P& r- g0 p: G( Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& N. U+ B4 b7 r (floor((pycor + max-pycor) mod grid-y-inc) = 0)]- [2 B- d# Q# z, c+ A' P
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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