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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。
% L( t; |- [' k0 Cnetlogo自带的social science--traffic grid这一例子当中,: @+ F! ~% O) ]% k, i
globals
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" H; h+ a! A3 t- q grid-x-inc ;; the amount of patches in between two roads in the x direction& _' Q2 C4 x; \ C* B
grid-y-inc ;; the amount of patches in between two roads in the y direction5 d6 d' i" t+ ?3 h# }7 k
acceleration ;; the constant that controls how much a car speeds up or slows down by if
8 K2 h( |, v5 i% [8 G& D+ y ;; it is to accelerate or decelerate. e C! n2 z7 ?. ~7 Z9 Q' ^
phase ;; keeps track of the phase! |+ h" _+ C. b3 o& N8 h
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure! T" {: s( \3 `( `8 v$ c
current-light ;; the currently selected light
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;; patch agentsets$ `2 s+ \% `8 i# b! h
intersections ;; agentset containing the patches that are intersections' C0 [) x6 X% ], t
roads ;; agentset containing the patches that are roads1 |$ B$ t1 J: |, T+ |+ g
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turtles-own
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1 r4 V2 U# H3 D" y/ D) N% J3 W speed ;; the speed of the turtle y% V8 _" a! c5 _0 _( s; z& o4 b
up-car? ;; true if the turtle moves downwards and false if it moves to the right& @) p+ G6 Z) L" L; v8 S( U
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
+ h) ?4 H8 u# k/ V$ s* [ green-light-up? ;; true if the green light is above the intersection. otherwise, false.
1 h7 _9 @, D" F ;; false for a non-intersection patches.
, `$ Z$ Y1 b+ g5 H1 R8 _ my-row ;; the row of the intersection counting from the upper left corner of the
& {: k3 A( o% n% `) n& m& V ;; world. -1 for non-intersection patches.
w, V* s6 z( @) g8 r my-column ;; the column of the intersection counting from the upper left corner of the. h3 \3 x1 w: G/ \
;; world. -1 for non-intersection patches.
' p( F1 U5 \$ P* s ` my-phase ;; the phase for the intersection. -1 for non-intersection patches.6 v4 |- X+ L2 H
auto? ;; whether or not this intersection will switch automatically.+ F8 p6 `/ s! J' ~
;; false for non-intersection patches.( N) p# A a. B/ J8 P
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% p" B! v9 S8 i;;;;;;;;;;;;;;;;;;;;;;
0 _2 m Y% k' _+ K;; Setup Procedures ;;8 H. H2 V1 m, F }) t* p, Z
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
/ B& {. X3 ?0 x0 r;; Create num-cars of turtles if there are enough road patches for one turtle to
) X( C$ T/ K; k! u, P6 S;; be created per road patch. Set up the plots.1 |( @. P g# [/ s& t" r( E
to setup
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;; First we ask the patches to draw themselves and set up a few variables
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0 g, J; _: B0 _8 f+ o- {. o make-current one-of intersections
) @9 s$ ?% B( Y: \ I label-current
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" l" X9 v! `$ I# s7 i) t J) h) B set-default-shape turtles "car"
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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 "8 B1 g& @8 ~* e
"road. Either increase the amount of roads "3 N' q9 H ~3 z9 Z( m1 H" W
"by increasing the GRID-SIZE-X or "$ y* z( l& P. g' x. {: }
"GRID-SIZE-Y sliders, or decrease the "
# C( i1 ~7 m* t( k1 U% f "number of cars by lowering the NUMBER slider.\n"
+ o9 P4 V3 x2 \' n& ]# D1 d "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 ? o* U! d7 I
crt num-cars
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$ v- N/ k6 P6 N/ n setup-cars
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& {" p9 E1 B) K5 ~- V" S8 m6 \ record-data
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1 J- A: f v2 _, m ;; give the turtles an initial speed5 _* w* N |* O8 Y
ask turtles [ set-car-speed ]
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reset-ticks
0 y& v: I8 w1 O6 ?% I" `7 D! `end
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;; Initialize the global variables to appropriate values0 ^1 S% E/ h, Y2 I
to setup-globals7 J: f4 k6 S$ W+ u( R$ R6 r
set current-light nobody ;; just for now, since there are no lights yet0 }! J, `; ]2 `, f$ h& W
set phase 0
6 Y* H0 p: M5 I- L) G, n set num-cars-stopped 0
. z! N5 B) a% M, ^" m( Q set grid-x-inc world-width / grid-size-x
: Q/ G4 E' \' h. n4 P, x set grid-y-inc world-height / grid-size-y$ w1 Q; {! K( g0 |) a; O
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary* ?+ I3 ?- w' Q$ [, B6 b+ d0 e
set acceleration 0.099
$ ]2 h% P/ ~/ Qend
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( ?9 X* \# m, F ]/ i9 P;; Make the patches have appropriate colors, set up the roads and intersections agentsets,& |# g* ]* ^, { a. x
;; and initialize the traffic lights to one setting, ^4 ^' Q, N8 ^) ~* H1 F, c
to setup-patches% i# |% [1 @- A$ z6 \1 C
;; initialize the patch-owned variables and color the patches to a base-color9 R& q" U" a* B& c6 V4 w9 A9 c f
ask patches8 m9 B4 F" c' c) Z
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set intersection? false
A6 N& u; F" U3 c5 Q: ? set auto? false6 f$ E# A/ W" D( n
set green-light-up? true% `% Z3 I; A& \% s/ t
set my-row -1
/ q- V3 [5 s) ] set my-column -1
$ `+ t+ P1 p* k8 H0 y; l+ L: p6 j set my-phase -1
* J2 q) d' V' a& C0 P) F9 N* ^0 D set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets( V4 x9 k$ Q# K% C4 ], A2 k( V
set roads patches with5 ]7 l" }* F9 k+ U
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 R% c# k( Q. @5 i
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. M6 ^3 M) v1 B! q
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ] I' h/ i- Y2 R/ c; s/ N
setup-intersections
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) v9 j% M) C: O, Q* d2 C其中定义道路的句子,如下所示,是什么意思啊?
/ ]- i9 [1 c, b+ k' z set roads patches with9 t# r& R. w9 m
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 A; }; F: I `: C+ ?
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- C2 N5 v/ N9 \5 Z q& F* w/ D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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