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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。
5 ?) ]" q! r7 X; _8 \ X6 anetlogo自带的social science--traffic grid这一例子当中,+ D7 d3 Z* q# s9 ^. i/ g4 R
globals/ V3 U, A& h5 E; [- t# M
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! v. e* @4 }& Y' w7 M grid-x-inc ;; the amount of patches in between two roads in the x direction+ K" d* K# x0 n. S
grid-y-inc ;; the amount of patches in between two roads in the y direction
2 w4 i1 m/ V \ acceleration ;; the constant that controls how much a car speeds up or slows down by if( w0 a; M/ L4 @/ h. E+ }
;; it is to accelerate or decelerate1 a5 `- P6 F- W; J3 @& x
phase ;; keeps track of the phase
; _9 R# h: q' B8 P num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 `2 c- l& ^8 Y; ` current-light ;; the currently selected light
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;; patch agentsets
; y; N+ H# F6 ^/ w7 }9 F2 v' b& B9 v intersections ;; agentset containing the patches that are intersections
! j+ v, S, X% O' ^+ b5 n- O roads ;; agentset containing the patches that are roads
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9 ^! ?) K7 p( ^. Sturtles-own
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speed ;; the speed of the turtle
! E" C% i- _7 ]- q up-car? ;; true if the turtle moves downwards and false if it moves to the right2 g& S+ e- q* O3 Z; | v; s# T
wait-time ;; the amount of time since the last time a turtle has moved" [7 |+ m. y3 E! f" h, B+ m
]
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patches-own
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% s$ n% c( S! k) f intersection? ;; true if the patch is at the intersection of two roads5 L: a+ ~0 G$ T& ]! S6 m5 H
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ R6 b; A; l E* l0 t; z. S$ ~* Y ;; false for a non-intersection patches.
3 T! D5 r& Z/ l+ z& X0 I my-row ;; the row of the intersection counting from the upper left corner of the
, h6 N+ E5 l$ F ;; world. -1 for non-intersection patches.
! ^$ n2 x1 P$ n4 o3 W8 w; V my-column ;; the column of the intersection counting from the upper left corner of the
: y+ u$ o6 Q4 l0 @$ p F2 i# W1 v# N1 m ;; world. -1 for non-intersection patches. @& K" `! d2 @ \1 m
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
7 t1 F. i+ ]$ u2 i/ U auto? ;; whether or not this intersection will switch automatically.
! ?/ k ?5 d) o& b ;; false for non-intersection patches.% H: x5 C- W# F) c, V
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;;;;;;;;;;;;;;;;;;;;;;
$ S- d/ b5 J' t+ A) w;; Setup Procedures ;;$ H- J+ O2 P; l" G- F/ ~
;;;;;;;;;;;;;;;;;;;;;;" x$ M1 |; y3 F; c! m
( g! |/ `1 P$ G- v% S6 o- L* p;; Initialize the display by giving the global and patch variables initial values.
2 ]4 I4 k# Y0 R;; Create num-cars of turtles if there are enough road patches for one turtle to- L$ ^: D2 ~/ r5 x& M
;; be created per road patch. Set up the plots.
/ }" d/ _8 `" S2 S: pto setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables! ~5 Z' C$ A1 P
setup-patches4 r0 L" o" r9 F* f+ U; h0 v" d
make-current one-of intersections; H* {# L+ v/ b& [- N: l
label-current8 f3 d( W5 X. M( D' c3 ~! u
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set-default-shape turtles "car": r2 d. g: a# R( J# q6 J/ C
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if (num-cars > count roads)
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0 e: L' M y F& r user-message (word "There are too many cars for the amount of "
8 q! U4 A9 d# F0 s3 a+ z "road. Either increase the amount of roads "
8 p- d. { T! @6 k4 n "by increasing the GRID-SIZE-X or "
2 `8 t& P y9 ~! ^; K2 n "GRID-SIZE-Y sliders, or decrease the "
- \+ d. ]" v9 t2 \2 @1 f u "number of cars by lowering the NUMBER slider.\n"
8 S: j" c, P' j "The setup has stopped.")
9 a1 x4 ^1 d( }: Z/ c stop4 b+ X+ ^2 F* a. I5 q
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
; I$ p+ N% p8 Z crt num-cars
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/ p* h% E/ k' y" _* ^: k setup-cars8 p9 m4 B/ L* Y9 `8 N- L+ N; X
set-car-color
! r! o+ b' D; K+ g8 b record-data
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4 j( r+ ?# O3 V7 ]' P4 n+ F9 Y. ] ;; give the turtles an initial speed
" ^ i$ }; z# V* x: Y ask turtles [ set-car-speed ]
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reset-ticks9 V2 T: N8 C. d5 y
end
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;; Initialize the global variables to appropriate values: ?; A1 I- A4 j U
to setup-globals# v% d! l" P! b
set current-light nobody ;; just for now, since there are no lights yet2 @8 ^6 E( `! W% F# l& h5 E# ]3 Q
set phase 0
; V' U/ g( o; P. q9 e @$ s set num-cars-stopped 0+ k! n, [6 [ a" u! \
set grid-x-inc world-width / grid-size-x
& Y5 A G/ i6 L: j: l set grid-y-inc world-height / grid-size-y
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0 l3 V5 B1 F, G ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary) s2 e$ ]" P: C! o
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
; d6 J& g; X3 C( c;; and initialize the traffic lights to one setting
H- y) r M' B1 Y' z3 nto setup-patches
& K* {+ T$ O0 e- `5 A) u1 q# r' z ;; initialize the patch-owned variables and color the patches to a base-color3 H5 y. v D% T3 m: [3 V7 v
ask patches- q/ K# j+ D2 v( J
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set intersection? false' c% H: q; S$ O8 D
set auto? false. d$ A- \" R8 z0 P7 g9 O+ M9 `1 O
set green-light-up? true
& l; |2 o/ u8 o8 O. e set my-row -1
1 h ^* ~+ R. b6 n( _8 b set my-column -19 D2 f3 o2 I$ D2 ]) s
set my-phase -15 X5 E, x7 t4 o) C/ V: `; p
set pcolor brown + 3
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, T3 G! x# p8 ~0 N; R( a$ s- u' a' K ;; initialize the global variables that hold patch agentsets, g, U: h4 q- q4 i+ V, W6 x
set roads patches with
$ Q4 M5 |' c2 m ~ t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" e. }8 T% v! f) J7 F- H
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: J. `/ H6 D; Y E8 q" G set intersections roads with
- X8 T# M8 h% _8 F [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
5 m, E) ] M) f0 a (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
8 P9 [1 t& t4 d& c* _ setup-intersections) H' g0 f8 ~( I2 J5 u& Z( b2 q
end
7 D; E' Q: \; g; {/ E其中定义道路的句子,如下所示,是什么意思啊?
, n, \' d+ U$ Z( [ set roads patches with
% M# ^* N0 D W- l z# y* | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& v- y3 M; u$ I3 e! Q" L+ O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]! s7 L! E8 s* S" o1 v6 a
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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