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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。
8 t( n! ]7 M8 r: A& snetlogo自带的social science--traffic grid这一例子当中,
% x! t3 y) O1 `% t9 @; I$ Uglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
- P; t0 J! c `9 H grid-y-inc ;; the amount of patches in between two roads in the y direction
: t/ T5 A* f# A# ^. K! B acceleration ;; the constant that controls how much a car speeds up or slows down by if6 ]% V0 x2 D" w8 x$ v
;; it is to accelerate or decelerate7 Q, N7 E1 h+ S" a
phase ;; keeps track of the phase' Z# U( C ~! E/ G" S
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure9 R8 j Q: m0 C1 L) Q8 ~7 [
current-light ;; the currently selected light
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( @$ f+ `# i" s6 c# g ;; patch agentsets, @ T* X M X2 p; [
intersections ;; agentset containing the patches that are intersections1 _ F7 n: h/ g7 p
roads ;; agentset containing the patches that are roads
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: U( b- i0 }2 sturtles-own
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speed ;; the speed of the turtle
7 V: L# L5 l7 \4 v0 N6 u0 ~$ U6 I up-car? ;; true if the turtle moves downwards and false if it moves to the right' Q3 y$ Y7 S! j5 m' E) @
wait-time ;; the amount of time since the last time a turtle has moved
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( a; t! q% a% m% n, J( I- \patches-own' i* L. Z, Y4 D( K
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intersection? ;; true if the patch is at the intersection of two roads
6 }6 F2 ~3 C( {' s) | green-light-up? ;; true if the green light is above the intersection. otherwise, false.
" G, h% r! z. u$ z ;; false for a non-intersection patches.
7 k" m: s8 f7 T8 V |/ s4 O my-row ;; the row of the intersection counting from the upper left corner of the9 u: x7 g, ?0 D9 g3 N, M
;; world. -1 for non-intersection patches., B7 }0 M( @6 m" ~
my-column ;; the column of the intersection counting from the upper left corner of the( x- E8 K b+ v6 s
;; world. -1 for non-intersection patches.& T) E2 A2 m% f" T. ]) ^( R& A) O; L
my-phase ;; the phase for the intersection. -1 for non-intersection patches.# ]2 u: O; J7 }
auto? ;; whether or not this intersection will switch automatically./ k- Y. j" \3 N& c+ g0 Q
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;$ h5 f9 G9 r: o/ B& S( Q& i& M% |2 h
;; Setup Procedures ;;$ J% _/ C9 B: Z0 G) {/ @
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;; Initialize the display by giving the global and patch variables initial values.6 k: F( o, P& P4 T
;; Create num-cars of turtles if there are enough road patches for one turtle to
/ i9 ~5 \6 [4 P0 A$ h v# s( ]6 c;; be created per road patch. Set up the plots.; a# ]' n$ x0 r- h- x
to setup8 C8 r. ~6 v8 {# N. X# M! ~: P
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setup-globals2 G+ C9 s6 I, _0 \% V0 \ U( [
2 U9 V4 {- A6 b ;; First we ask the patches to draw themselves and set up a few variables
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make-current one-of intersections1 C/ V& u( x' c, I- ?
label-current
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& Z( m7 ?' V/ D# l6 b: }6 z set-default-shape turtles "car"
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6 P" H5 b$ [) F/ \0 F if (num-cars > count roads)
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5 l; `. ^/ d) w+ S; i* B! F- [. ]1 F user-message (word "There are too many cars for the amount of "1 Q& }: E5 w) W1 i! D
"road. Either increase the amount of roads "2 R) U0 B0 s4 I: h
"by increasing the GRID-SIZE-X or "" z& s" r0 I' E6 l
"GRID-SIZE-Y sliders, or decrease the "
) _% c5 b4 {) o "number of cars by lowering the NUMBER slider.\n"
9 d0 z7 V* D% c% o$ y; w( O, u "The setup has stopped.")% G- K6 v: W5 S+ ~$ ]
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color0 q7 N' l/ G: P: I' c& b
crt num-cars' \2 M' z% K/ Y
[
" M% t! \+ B0 y6 i& v/ d/ x setup-cars6 O. a0 F; c3 y+ M4 r
set-car-color0 I- f" a% C2 w- u* V
record-data
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;; give the turtles an initial speed3 C5 H. O+ r! u0 U8 Z
ask turtles [ set-car-speed ]
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2 |4 \5 S3 r, F0 Z a; ^# N& ^ reset-ticks3 G& u0 Q1 A: I0 m( V% U& {
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;; Initialize the global variables to appropriate values
9 r2 A9 s; U# J5 A# N9 | Eto setup-globals5 t. H* v7 h% D, h) C
set current-light nobody ;; just for now, since there are no lights yet8 ^5 F2 n( [) d; t8 W
set phase 0
' M, Q! K: I' g4 s# { set num-cars-stopped 0
! x5 e$ `- K \- ~6 [ set grid-x-inc world-width / grid-size-x# \- r8 R, H* K5 U, J
set grid-y-inc world-height / grid-size-y7 H: P1 R0 H3 d/ R2 Y9 Z- D
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
5 z9 u( t# C/ \) P4 E# Y set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,0 e) M: ^( [# b. D* L) {( Y
;; and initialize the traffic lights to one setting
, |7 @" R- g0 C8 r6 o9 c# _$ C* n2 f9 B2 jto setup-patches( e9 r# w, H# B' P5 A9 i
;; initialize the patch-owned variables and color the patches to a base-color. U q& `% u* m2 ~0 ?
ask patches6 p8 L1 |* L! f1 B! w
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set intersection? false( L: t& x' T' A& @$ d% W& ^& I
set auto? false
" e3 O I% m; k# i7 L1 l, b set green-light-up? true
3 h# ?+ F8 h: N* _8 A/ ] set my-row -1" W- e9 U/ s7 `" ^8 P% s
set my-column -1
8 U" b. v3 i) q% t2 v5 }+ g+ h set my-phase -1
7 z7 ]! d9 r4 N. Y# @) F set pcolor brown + 3! E, t+ l: L( V, v
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;; initialize the global variables that hold patch agentsets
% V6 [. d4 S s set roads patches with
7 Y! Z" Y2 o! q* O0 R [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 C+ r) y0 }- u (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 `* Q3 a; @8 |5 G8 h2 t; L
set intersections roads with
* B! j: W: e. Y3 W0 C* H; { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and' L+ N6 a, v. P' s: s( e
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 l2 x6 i3 n/ j. [$ g
6 N' ?+ w3 W+ q! b ask roads [ set pcolor white ]7 f7 Q* i5 Y6 H
setup-intersections% K5 I4 S& `3 M+ u: c
end
; Y* |; s& C# [9 S4 j% q其中定义道路的句子,如下所示,是什么意思啊?: D/ q5 t' ?3 L+ |0 z
set roads patches with
- s% e$ a- ~3 Q! Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 d* ]0 Y: |- @: }1 w0 k# u6 j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 B! J, d1 O& ^5 @' q! g$ `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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