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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。
* Y5 O" f" x3 M4 m9 q: R4 fnetlogo自带的social science--traffic grid这一例子当中,2 f5 O R3 d- G4 u5 f
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction6 f& d9 A% h: ` L# R8 p
grid-y-inc ;; the amount of patches in between two roads in the y direction
% L. H4 y% {! N: m' |3 C acceleration ;; the constant that controls how much a car speeds up or slows down by if6 Y; [. N5 k* m3 |% ?1 o$ _5 [
;; it is to accelerate or decelerate ^# h$ W- a$ u4 N
phase ;; keeps track of the phase" c$ ?: r, m- h; e6 [/ k* L
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
1 Y7 s/ H) `: E* H+ l/ {& S current-light ;; the currently selected light
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;; patch agentsets; J/ o' w( ~* u* L. y7 d5 R/ d
intersections ;; agentset containing the patches that are intersections
4 G8 F1 s& _8 R2 v roads ;; agentset containing the patches that are roads' }% K7 x: \+ B; C5 a
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turtles-own
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) b0 W' Y0 @. F' C7 Q; k speed ;; the speed of the turtle! m" i1 ~- I) G3 s& @6 i
up-car? ;; true if the turtle moves downwards and false if it moves to the right
- @0 L' p/ k) ?1 S2 C- V wait-time ;; the amount of time since the last time a turtle has moved+ B) O, e! Y! J9 x( t$ A
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* N% E& D; S- ?0 spatches-own
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intersection? ;; true if the patch is at the intersection of two roads1 \; e1 x6 _0 J
green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 f8 G3 b5 |+ @4 J# q, g
;; false for a non-intersection patches.8 B7 A2 ]* L; j
my-row ;; the row of the intersection counting from the upper left corner of the1 R3 J# V. N# L3 r: x4 R2 e
;; world. -1 for non-intersection patches.
2 S; ?0 K# [1 A& S% N3 U7 h: ^ my-column ;; the column of the intersection counting from the upper left corner of the
& W3 [8 A8 `' d! ~1 G+ Z5 X) t g ;; world. -1 for non-intersection patches.
' L* {) R' ^2 v6 j my-phase ;; the phase for the intersection. -1 for non-intersection patches.
" L5 Y: A3 u# q3 j" _ auto? ;; whether or not this intersection will switch automatically.
S: `/ v/ r+ r& j ;; false for non-intersection patches.
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3 q$ j5 o. t7 C;;;;;;;;;;;;;;;;;;;;;;
7 I* @/ e' t& c# I;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.
/ A" F$ J' A& m: @% |7 u;; Create num-cars of turtles if there are enough road patches for one turtle to" x0 y0 A7 v8 H# `+ f
;; be created per road patch. Set up the plots.
3 T' L9 L! D8 n3 _1 p2 m2 }to setup4 \/ j& e) A9 a( g2 j, g5 k" N- }
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
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S6 z. s' p2 o9 ^/ x make-current one-of intersections
2 N7 p; L- N$ l+ k& i label-current
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5 P% ? k% b, G- [/ x! N set-default-shape turtles "car" ^' Q( m: R1 \7 @
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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 "
7 B' ]/ ?# f" T) B: m3 J "road. Either increase the amount of roads "
9 `& |9 d1 W: x# f "by increasing the GRID-SIZE-X or "8 i& p: k g* u4 C# n9 N' I
"GRID-SIZE-Y sliders, or decrease the "
% I( I& E, l7 c1 H+ l( G' [ "number of cars by lowering the NUMBER slider.\n"+ M! }# k9 S5 v3 U# X4 Y: M/ R
"The setup has stopped.")
, d+ \! N* {, {; o' O( e stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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set-car-color" z; n* C* o6 [4 ?- k% u. o
record-data% J2 k$ e4 Z( }, T4 t
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0 |% v4 i6 r$ Q ;; give the turtles an initial speed" m* r9 B2 y. K2 Y* @
ask turtles [ set-car-speed ]& f8 O( q1 |% B& H5 t/ w
- ^, v# j: h; _/ M* b reset-ticks& D4 ^2 n4 w( [3 j9 ~
end
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1 O7 B$ x* R( w' K;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet4 p0 T- t% b( S% ]& t
set phase 04 U$ K, r4 V7 W, E o
set num-cars-stopped 0- o/ s4 i2 @% ?
set grid-x-inc world-width / grid-size-x8 U& G1 {& w3 o+ n' u3 r7 t" O, T) \
set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary9 f6 S5 w& m9 d6 C+ ]
set acceleration 0.099
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! _- S: e$ ]% O0 k; w6 o* Y0 `, C;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
, o2 X( C0 Z7 B) p( [6 i9 M;; and initialize the traffic lights to one setting
3 O; _' l4 P, u* Z2 \6 d( Mto setup-patches
* \" ?8 m( O6 l ;; initialize the patch-owned variables and color the patches to a base-color# q- G$ b# ^/ x. M1 D
ask patches
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set intersection? false
% p, e' V3 n7 K/ G* M% Q7 [ set auto? false5 J e; P1 z1 `, e8 j+ B; ~
set green-light-up? true
, L* d% j" {0 ?4 f+ D% x! N set my-row -12 L ^+ Z8 H) h' r9 Y$ l' N) x$ C$ {
set my-column -1
% D) Q9 R3 v0 W5 @ set my-phase -1" z' F, u) a: [) m7 a9 g
set pcolor brown + 38 G# m4 I {) }
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;; initialize the global variables that hold patch agentsets
7 L ~ c6 Z" u8 U# i& u7 U set roads patches with
+ e& t$ f# H/ C( N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
B6 I, ^$ S A1 i. C (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: P6 d( @7 P5 s0 [$ g set intersections roads with
7 C% Q& N' A. R& W1 ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
! |6 m0 D$ A6 ^ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]) I$ i3 E3 ~3 Y. b; o9 x6 \: S$ [
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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?
8 q2 [9 {7 U1 w* ]* o( |5 { set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 W: F' h! C9 S' a1 j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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