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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。- C0 s: L V6 n' s7 o+ p# ?$ ^
netlogo自带的social science--traffic grid这一例子当中,
; i0 k) w$ t- x4 z2 A. b# ]globals2 w& L" u. b4 J: T/ s. ]/ Y. L
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grid-x-inc ;; the amount of patches in between two roads in the x direction
9 g' ^. P% C6 X. e grid-y-inc ;; the amount of patches in between two roads in the y direction4 s* g2 d/ z& L8 E- n
acceleration ;; the constant that controls how much a car speeds up or slows down by if0 O$ [( t+ I1 i$ M) B
;; it is to accelerate or decelerate
- D6 l# S3 [# y | phase ;; keeps track of the phase
% b9 p8 a$ N( V! i6 Y/ {4 S num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure* }9 B7 O4 i$ x e% T2 f7 g
current-light ;; the currently selected light" V7 v: ?% Z: i& E1 f" P# o# P, }
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;; patch agentsets- e1 f' Y2 B( `# V
intersections ;; agentset containing the patches that are intersections: O: a! v7 e1 v: y8 x
roads ;; agentset containing the patches that are roads, g8 _" W& ], @) W4 y9 M4 D/ K/ H
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turtles-own$ I% C9 ~, B5 W+ Z
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speed ;; the speed of the turtle; X2 j: I. z3 }8 J0 d
up-car? ;; true if the turtle moves downwards and false if it moves to the right
& x# G* p6 |! V4 A wait-time ;; the amount of time since the last time a turtle has moved: q$ f! q& z5 d
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patches-own) `5 K7 U6 A9 W1 ~5 U
[
8 H. m% G) `- H* H0 t8 B' ^# S intersection? ;; true if the patch is at the intersection of two roads1 X5 t' v! d# |* r0 m
green-light-up? ;; true if the green light is above the intersection. otherwise, false.2 h, |, Q7 u" |" O+ Q h% [
;; false for a non-intersection patches.8 M! e5 c! N6 T2 @$ I" x6 N3 e
my-row ;; the row of the intersection counting from the upper left corner of the6 o, q" d, ^9 G5 J" S
;; world. -1 for non-intersection patches.
" w# k- s- B8 F+ { my-column ;; the column of the intersection counting from the upper left corner of the& `9 d+ d! \1 ^
;; world. -1 for non-intersection patches.
: _# N% i0 O1 x4 H- l7 S v* d my-phase ;; the phase for the intersection. -1 for non-intersection patches. e& y( o7 ?! k3 p( e
auto? ;; whether or not this intersection will switch automatically.: B! Q1 K+ M1 a; s7 j# k( z
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
9 e. k3 m3 K# }& A* y;; Setup Procedures ;;
# b' ?6 E L; r ], ?& F# P# K;;;;;;;;;;;;;;;;;;;;;;9 W! d9 b' F5 C: v/ _: W+ M
5 j; z& c2 M9 @6 c;; Initialize the display by giving the global and patch variables initial values.
$ `1 j# A- k& q4 W% c4 h;; Create num-cars of turtles if there are enough road patches for one turtle to
$ T8 T5 q- X. R;; be created per road patch. Set up the plots.
3 H/ [% d- k3 V% ^/ d, b; s( F3 Mto setup# Q t g& `8 X$ i& D
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setup-globals* l: a- Q( i) t* E3 @; K, l
& q1 T- b' G! j+ E* X ;; First we ask the patches to draw themselves and set up a few variables( p# W1 h* \6 d! {. C
setup-patches' m" W* R# q- D
make-current one-of intersections
' I- X4 m$ P; D2 e1 r label-current, E4 F, B% J% w
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set-default-shape turtles "car"4 d6 |% X" m/ e# W$ @' u' _
9 Z1 L4 s' o' l! w; g; u* g' ^& r1 P if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "/ j6 z* J ?2 z9 g9 j
"road. Either increase the amount of roads "8 ~- }3 P/ {8 [! w
"by increasing the GRID-SIZE-X or "! v. L2 d8 M4 u# N2 p: c% N* G; q
"GRID-SIZE-Y sliders, or decrease the "- U: K* I- K E
"number of cars by lowering the NUMBER slider.\n"/ e( _0 u3 I6 M# S' S$ M
"The setup has stopped.")
7 b1 z( t$ g6 m# P stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color9 D# e3 d3 w3 B$ N7 y
crt num-cars
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/ g3 \6 }6 n" _ setup-cars2 [* j$ m& T5 B( b2 Z1 \% X
set-car-color5 N& `. }2 z/ S: j9 X
record-data' v7 [/ Z7 p; y& v
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) \- c' Y; C* X/ e7 a k* }3 _ ;; give the turtles an initial speed
4 j1 I( s2 F5 U1 o" a9 d" t; d: y ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet
9 f C8 `, h# u& v6 O4 \& H set phase 0$ c r8 I) H% G9 Z: c
set num-cars-stopped 01 d8 j4 v9 i5 \5 |
set grid-x-inc world-width / grid-size-x9 d" P3 s! }) C. m ~# c4 Y K8 G
set grid-y-inc world-height / grid-size-y3 f) p' f4 a1 s
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary f, h* K Q' E* R- _! @8 G" Y2 x
set acceleration 0.099
2 x1 V- \, k# {# _0 qend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
- b7 Z& z1 F" {4 d2 [;; and initialize the traffic lights to one setting/ T1 }0 |2 p4 A5 _8 }3 M
to setup-patches/ a* u. n3 P3 L J2 @6 ]. E& |/ I
;; initialize the patch-owned variables and color the patches to a base-color+ F R! |, C: u% E, L
ask patches
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set intersection? false3 P/ `7 f# O7 {6 t! D! p
set auto? false
- d7 {# k1 b2 T set green-light-up? true: g5 Z# i3 M! x2 m% l
set my-row -1
/ [9 y# L, C' K set my-column -1
6 ^( I' t! E5 K7 F! Z) H& c set my-phase -1
( h& H/ N, o+ J* P2 a; Z set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
1 w$ g7 i! m; J8 x; I* F set roads patches with! I$ f& K" X/ a) L# G
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or# k# g" N" s7 @0 z7 l, \
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 }- m. h0 \* M# d f& {' M
set intersections roads with# U: k$ |9 ?( N C
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
% W `# \3 V9 H% K, v1 b (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; o1 w. t4 c3 v: t
( J1 Y: _5 {' I0 U9 ]8 `! [ ask roads [ set pcolor white ]9 z* G# K5 P5 \: ]6 x0 K# A
setup-intersections1 e& e9 o( ? Y! C- @
end
8 M, O3 Y* u4 w! m# W7 Z其中定义道路的句子,如下所示,是什么意思啊?
4 y3 c9 A6 o6 [+ q2 }$ E set roads patches with1 O- Y& h$ S$ l8 g$ z2 G
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ K7 _. n) q! y& C! {3 p# D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 Z( i" J8 ^" b6 h$ @* L! q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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