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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+ V/ B. D+ Y Tnetlogo自带的social science--traffic grid这一例子当中,
) ~" x; S; [$ {6 ?# Mglobals
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: B, [- [) F z' }* Z( v: ] grid-x-inc ;; the amount of patches in between two roads in the x direction
- B: N( U- i" q3 B grid-y-inc ;; the amount of patches in between two roads in the y direction
8 j3 D4 u( V D! T: \ acceleration ;; the constant that controls how much a car speeds up or slows down by if
4 u$ L4 ~! H" H0 o ;; it is to accelerate or decelerate
; j8 p. ?& k& ? }' j phase ;; keeps track of the phase8 m, }8 O: g$ N, |' z7 a* g& v* Y* ~
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
" L. O4 }9 m4 {# B, j* P" n1 g current-light ;; the currently selected light
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0 n; X% F, ^: n: I V ;; patch agentsets
0 p! d5 [/ @- _8 {* O' I* n intersections ;; agentset containing the patches that are intersections4 p* _8 v2 `1 B* Q
roads ;; agentset containing the patches that are roads
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turtles-own
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' g; L C; B: b8 @* w% G speed ;; the speed of the turtle
6 W: w9 y* z& Z X, @& b3 e up-car? ;; true if the turtle moves downwards and false if it moves to the right4 a1 _% Y; T( S
wait-time ;; the amount of time since the last time a turtle has moved+ k6 O* ~" P' [/ M$ t
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patches-own$ p5 n1 j! ~) Z( ~" R
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intersection? ;; true if the patch is at the intersection of two roads
9 U$ ]8 u6 z; T# Z/ X green-light-up? ;; true if the green light is above the intersection. otherwise, false.
8 w& a9 Q C1 }% u$ V+ y) h" V ;; false for a non-intersection patches.
4 O1 H3 Z: p7 `' Q; r' A my-row ;; the row of the intersection counting from the upper left corner of the
4 V G% ^1 ]8 v ;; world. -1 for non-intersection patches.
8 r3 ]/ J+ ]6 e! \; X my-column ;; the column of the intersection counting from the upper left corner of the
8 T- C; H6 J2 J3 P ;; world. -1 for non-intersection patches.4 p$ y9 I/ Y& d, t6 G e7 \6 t% h
my-phase ;; the phase for the intersection. -1 for non-intersection patches." B& s! O# V. B$ d
auto? ;; whether or not this intersection will switch automatically.1 e) `/ I, U, M
;; false for non-intersection patches.) ~7 V4 p- O$ }! v% H4 ^
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5 d" ~. J0 h7 R) X9 B0 {& I1 V: A;;;;;;;;;;;;;;;;;;;;;;1 [- N L, C* @0 H! b) |7 K+ U# f
;; Setup Procedures ;;
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; @8 F$ U# S: \- [! g;; Initialize the display by giving the global and patch variables initial values.
3 ~ b/ V( v5 l, q) h- R. @;; Create num-cars of turtles if there are enough road patches for one turtle to1 a3 Q; ]$ @% e& Z
;; be created per road patch. Set up the plots.0 C: Z5 `5 z# J
to setup
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setup-globals. C6 t/ x0 D0 {+ y
2 e' Q( s, G% e: R9 J6 H: V& T ;; First we ask the patches to draw themselves and set up a few variables4 N! M! ^# }1 Y& C P8 o
setup-patches8 l) P9 @& m1 ^! b
make-current one-of intersections- i7 B6 _8 s% e8 f- `
label-current
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set-default-shape turtles "car"
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$ r% V' {7 H; }. v" c if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of ", A. h! q) b% f3 u
"road. Either increase the amount of roads "/ K; S3 b# O2 j4 b* p, x7 m
"by increasing the GRID-SIZE-X or "
7 T1 [3 `+ _. Z$ c9 O "GRID-SIZE-Y sliders, or decrease the "; I0 E$ p2 C' T2 k
"number of cars by lowering the NUMBER slider.\n"$ W8 ]; @0 X1 e5 b5 X# h
"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
0 \+ S$ o: m* L crt num-cars
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setup-cars
3 \8 ?/ Y: b/ j$ v+ C set-car-color
& Z& x* a: m# j7 P, A record-data
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;; give the turtles an initial speed- v, k% O3 N t, D) Y' L, j
ask turtles [ set-car-speed ]3 y# y# s3 S6 O7 O7 X; w0 ~
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reset-ticks: @6 N6 W+ \! b, c6 ]# z
end
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) x L, R: h0 p2 s;; Initialize the global variables to appropriate values
* _) h5 s$ q1 Y& [* C. {2 G3 ^to setup-globals
" a6 T$ U9 G1 m set current-light nobody ;; just for now, since there are no lights yet3 Z, E% |1 @6 ~
set phase 03 Y& `' g7 x: y( O# {) |0 S
set num-cars-stopped 0
, ] j* N" E8 F% u8 M& k set grid-x-inc world-width / grid-size-x" Q! h& m5 X% [4 I2 V& Z' w
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 boundary
7 l0 B3 g" W S: D# _% j set acceleration 0.099
?9 M( B$ `; T3 w kend% I4 ]9 e+ q1 x" F
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
9 S! r$ M: y+ I# @9 P2 k;; and initialize the traffic lights to one setting+ `1 D7 l7 L$ X2 h+ k+ U' u* k% E, } \
to setup-patches; _' p8 @) Q3 t+ U$ G
;; initialize the patch-owned variables and color the patches to a base-color! m! s- D5 A3 c9 d) q8 V3 _& V
ask patches h; o/ [) r2 }5 ]. v+ \/ I( b
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set intersection? false N: D8 q, j2 f# Y" G
set auto? false- L6 B9 o0 I0 I# @( m! C* V
set green-light-up? true7 k6 _. ?- g1 v% o4 d) j
set my-row -1
5 \# Y4 ^: _( S! K set my-column -1
2 \% H: |6 \- K/ t' S9 | set my-phase -1/ a8 ?; O3 l4 ?4 E3 ]
set pcolor brown + 3. k* r5 |8 z2 K# }/ O P$ W
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w4 c8 U3 R- S# d3 C ;; initialize the global variables that hold patch agentsets0 c9 j( |. W8 r6 g
set roads patches with
1 g/ O& g$ ~8 }- P4 o4 T! b3 T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ m- [; l- J" i& n/ A3 C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 Z1 D2 @- K" n. u( v9 V+ W7 ^ set intersections roads with% R8 l1 S8 t2 [8 n) E
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! X$ U( ?2 J2 ]1 N8 T
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]! M" V0 o1 n" }( [ W) U
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ask roads [ set pcolor white ]4 x/ j/ d+ z) v3 `5 `) o
setup-intersections* T5 z/ d; k8 `$ J7 h
end
1 N6 @+ g: x6 q. b1 c8 o* v* L# s) M其中定义道路的句子,如下所示,是什么意思啊?
3 }# X/ S" ~: i( v( ? set roads patches with/ J! a, _" {6 g* g$ ]( D
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) F9 \4 c% g5 A9 x8 }% [" s
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% x: i5 {4 W% L1 m3 v( }
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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