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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。
, Y7 E( M" s. _netlogo自带的social science--traffic grid这一例子当中,
. Q0 h5 N- s2 o6 o3 { \+ `/ Lglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
, }+ P/ x/ d. \& N- z. o grid-y-inc ;; the amount of patches in between two roads in the y direction: @2 w! X5 _9 S3 H
acceleration ;; the constant that controls how much a car speeds up or slows down by if6 F% A$ |# h) H3 _( p) f# c5 E$ A
;; it is to accelerate or decelerate; a; J+ N. f5 e! h$ m( T0 B* q
phase ;; keeps track of the phase
, W4 N! U8 p) n0 W4 y num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
7 y$ ]4 ]% @5 @% D, E9 \& G4 N0 o current-light ;; the currently selected light5 _' x; b8 x% {' r
/ e0 [( ?3 a% A: Q ;; patch agentsets
r* |3 ^# q, j# s: e intersections ;; agentset containing the patches that are intersections
|. p5 p4 s/ b* L roads ;; agentset containing the patches that are roads% }) C" J8 o4 s4 |; J' P J
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turtles-own5 F# H( X) e" m& _, l/ R
[
* v4 |5 e0 T: [9 q# l& f" m speed ;; the speed of the turtle
4 i0 r: g) c0 }/ g up-car? ;; true if the turtle moves downwards and false if it moves to the right
9 j( T' k4 y5 t! z wait-time ;; the amount of time since the last time a turtle has moved8 i" G$ l G7 m0 G5 a. D4 x
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
* j) e# s" A' l7 I6 a3 O green-light-up? ;; true if the green light is above the intersection. otherwise, false.
& k* m! w5 [) ~$ b# N1 s" b ;; false for a non-intersection patches.
. g* i+ Z" R1 ^# `( \ my-row ;; the row of the intersection counting from the upper left corner of the- G3 C; P& j5 g$ I! @3 [9 h" ]
;; world. -1 for non-intersection patches.1 u) z4 i! L2 k% [6 F
my-column ;; the column of the intersection counting from the upper left corner of the
5 u- K! [7 \* U. X2 { ;; world. -1 for non-intersection patches. l5 B9 r/ N% H3 b
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
! }) {$ f7 ^7 w" S0 v2 b# G auto? ;; whether or not this intersection will switch automatically.
- @2 a- p& q: o- {% t: C) `# H4 I ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
' `, ~. O3 A- V;; Setup Procedures ;;
% Y5 M/ ?1 m% P V;;;;;;;;;;;;;;;;;;;;;;
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% u3 H1 f# l& q;; Initialize the display by giving the global and patch variables initial values.1 ]- I. C) ?, \# o
;; Create num-cars of turtles if there are enough road patches for one turtle to; Q) S: b5 d" |% E* J. x
;; be created per road patch. Set up the plots.7 @: E) I/ O1 \$ n* G; ?
to setup2 {5 v: ~6 I) ~& G0 f* B. k S" L
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables) f- F) k# G# R: n" ?$ s" I v
setup-patches" e2 _* D& i4 g9 C( `
make-current one-of intersections0 E5 I" }: C- t2 v1 M7 n
label-current
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set-default-shape turtles "car"! B/ z0 E/ f$ K! T ~7 i
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if (num-cars > count roads)2 q5 F; _, d& M2 k) x! |( T
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user-message (word "There are too many cars for the amount of "6 e$ }5 g# _- Z/ x, m4 o+ O" X. J3 q
"road. Either increase the amount of roads "
' o9 s, Q' I6 y# }3 G* g; b "by increasing the GRID-SIZE-X or "
6 P, X' K1 M4 w7 `+ i8 Y" @: [ "GRID-SIZE-Y sliders, or decrease the "
# V5 v# w, ?9 N* ] "number of cars by lowering the NUMBER slider.\n"
" ]) `, o% q. W T3 U" `+ N$ d "The setup has stopped.")% q0 m U5 I2 e9 L( W9 D2 q
stop9 x/ A l0 o6 l; R4 i& R
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
% m# I4 R. P' ]* J- F6 [3 x crt num-cars! n9 b2 Z9 S" W1 v
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( l+ n4 \8 P+ A2 c setup-cars0 p* S7 b7 C/ I% V
set-car-color" p' l" Q8 U2 U" {6 F. D( s
record-data
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- g. D2 t9 _) r* ~& O$ C% N ;; give the turtles an initial speed
J1 L3 `: w; U. l ask turtles [ set-car-speed ]& u: x" K6 H* e8 A% i5 z9 |4 y9 B
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reset-ticks
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' @9 H. l8 M5 c% @- K1 E7 A;; Initialize the global variables to appropriate values+ v3 [0 W Y% h/ P1 z/ t
to setup-globals2 C- ?2 G5 J% R& o8 ]4 A4 Q: @# b
set current-light nobody ;; just for now, since there are no lights yet
8 k) v4 b& k1 z z set phase 0
: z: E" c* [* ^9 Q set num-cars-stopped 0- G' m* r' a* t
set grid-x-inc world-width / grid-size-x
. I5 S% j: S# h7 ? set grid-y-inc world-height / grid-size-y* P5 t1 I/ U U) G
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
1 R# U/ b3 l& L set acceleration 0.099# V4 n9 D3 |! q- {
end& J3 Z3 a7 F5 C! D r+ \
& V! {; H `6 P( l;; Make the patches have appropriate colors, set up the roads and intersections agentsets,* g0 Z+ w9 L* {& w2 _9 U
;; and initialize the traffic lights to one setting
5 E. u: J3 P4 t( d' r+ oto setup-patches, `) D8 Z4 s6 Y: I6 i+ e5 Q
;; initialize the patch-owned variables and color the patches to a base-color2 K3 q& n4 B Z% V
ask patches8 V8 }. ~2 X, W8 e
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, o7 z$ |# K1 j0 F8 S0 U set intersection? false) n X- }1 y% q/ | y3 z
set auto? false
p( q$ K4 H, @ set green-light-up? true l! |3 `' U! I7 H$ }; T9 d6 `& u v
set my-row -1& ~7 P# I1 J$ [+ v
set my-column -1! `* X6 D+ g1 j6 X4 t( Y; c
set my-phase -1+ n# s" y& q% w0 E7 a
set pcolor brown + 3# q" S3 x' B; K1 ~, K" ^
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5 p) [' f% x9 N3 J0 E4 W4 h ;; initialize the global variables that hold patch agentsets* Y: t: O: m4 x' r
set roads patches with
/ M; Z9 R: u g& f [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ v' y! |- q( y/ F/ T# t0 @
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" ]9 q6 x' U+ L4 C6 c( x set intersections roads with- b; L$ Y I( _+ M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and% _- }, z' ` A' Y8 q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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k9 j6 k6 H0 H& _- n( C2 [! e ask roads [ set pcolor white ]
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其中定义道路的句子,如下所示,是什么意思啊?
7 L- d' R2 I9 O& j6 M( ]9 G set roads patches with! F3 U4 M* ]& {. z, ?4 ~- P( U
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 G6 k5 t" {! C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 p- L* {% m% n7 j8 X
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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