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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% @6 I5 E% {% Lnetlogo自带的social science--traffic grid这一例子当中,& E2 O% _: _, b9 Y# n
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction/ L8 q- c2 w# a% A4 `; N5 C
grid-y-inc ;; the amount of patches in between two roads in the y direction5 l- v, S- d4 g0 j
acceleration ;; the constant that controls how much a car speeds up or slows down by if5 O0 ~7 h% w5 F9 V4 C5 z1 T
;; it is to accelerate or decelerate
# H3 J2 g3 \# A# G% Q. E) y phase ;; keeps track of the phase% c6 y: g% g7 z/ c, L( V
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure5 s* v, B: ~5 V6 j& g
current-light ;; the currently selected light
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: R# M: }" H* C* ^( E$ S ;; patch agentsets& w- `* j$ y' H+ P% r0 V% i
intersections ;; agentset containing the patches that are intersections
) i8 g* c. @ a- |$ W5 V roads ;; agentset containing the patches that are roads
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turtles-own; w' n( N z1 m. t
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speed ;; the speed of the turtle
7 L0 q- j% h5 P8 o2 ?+ N* T up-car? ;; true if the turtle moves downwards and false if it moves to the right
t( D1 E' H( U4 D6 L! T+ ] wait-time ;; the amount of time since the last time a turtle has moved
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patches-own. s6 S' \, r; V; e% `" f' _
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% D. m- b! G7 i# S; t# _ intersection? ;; true if the patch is at the intersection of two roads) r! i2 x' a9 D/ F# I) \+ v7 l
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
; w" {6 ]. O8 l1 V' K- c: a ;; false for a non-intersection patches.2 c8 a: a$ o, u: o; m2 a/ S: q8 p8 R5 P
my-row ;; the row of the intersection counting from the upper left corner of the
5 d0 {( c3 X& h ;; world. -1 for non-intersection patches.
2 n3 P! i1 h9 Y. {3 D my-column ;; the column of the intersection counting from the upper left corner of the* J& a: W' q* L( t
;; world. -1 for non-intersection patches.
+ w4 C: b/ B; v3 l R" M) W" C# T my-phase ;; the phase for the intersection. -1 for non-intersection patches.
2 n- t* K$ [! E5 G# j z auto? ;; whether or not this intersection will switch automatically.) w8 n, \( ?% }& m# R; j& V. p+ A
;; false for non-intersection patches.4 l( o9 x5 A; }5 y
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9 [( X/ K7 F; C: Z( t;;;;;;;;;;;;;;;;;;;;;;
+ @% s$ Z B" s& C4 k;; Setup Procedures ;;
# u% Z3 N. y8 c/ c;;;;;;;;;;;;;;;;;;;;;;5 m& B Z' \+ X, J* W
+ e$ u% y8 ^/ s/ ~" ~! R% @1 d;; Initialize the display by giving the global and patch variables initial values.
& j9 H7 \+ i, C. V! S! |;; Create num-cars of turtles if there are enough road patches for one turtle to/ |$ G, T4 e. K# K/ |5 U
;; be created per road patch. Set up the plots.4 k% ~. x7 q& _
to setup
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6 p1 F8 o$ [0 h; j/ C$ h) o setup-globals% c+ u7 b1 p1 K! @7 F
) B, H' z3 @7 A6 _. i9 j# w5 ] ;; First we ask the patches to draw themselves and set up a few variables: B/ _. N" ]0 Y0 ]0 X" E
setup-patches; G2 ^7 c+ W9 q8 @, l: j- |8 M# T
make-current one-of intersections
) F/ h) l& L9 x' t. A+ h: w label-current- W: E9 e: V t; \0 h7 g
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set-default-shape turtles "car"
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if (num-cars > count roads)
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- D3 o! M6 n$ o3 C; }" S1 p user-message (word "There are too many cars for the amount of ": C- @: s* V4 @; K. [, E' I
"road. Either increase the amount of roads "& O8 z- n3 a; ?; ]: ?
"by increasing the GRID-SIZE-X or "
7 Y6 S8 S4 x6 |* o d/ O "GRID-SIZE-Y sliders, or decrease the "
5 S4 ^$ F( C, T, l "number of cars by lowering the NUMBER slider.\n"
/ T: B" K6 O( o3 W) A "The setup has stopped.")- ~! B+ ~" u: r
stop2 _6 l0 t1 x# G
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: ~( |, w9 ^, P% S! E2 V$ [0 B ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, g; I( ?5 A1 W# s' m
crt num-cars
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setup-cars1 j7 Y: }8 }, Y/ C
set-car-color
$ ^! \- S2 J6 t" y! r6 p; g# V record-data
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;; give the turtles an initial speed
% @- V' F7 n# m3 K ask turtles [ set-car-speed ]
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reset-ticks! o P" T7 m3 b+ G# `/ c/ P
end
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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) V+ }3 u+ X! G3 R- r5 X3 v
set phase 0' n/ v2 u5 D3 |- Z& C' N
set num-cars-stopped 0
: `* F! ?5 E: `- j' j7 G7 [9 { set grid-x-inc world-width / grid-size-x; `; R5 n# H2 U$ {* E' ]
set grid-y-inc world-height / grid-size-y
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/ H0 R2 W1 q% @& i$ F8 C$ d$ C0 X ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 A4 a' M" [( @. a. v }- y* e
set acceleration 0.099
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; l; T8 T u- P, `3 o3 a1 {;; Make the patches have appropriate colors, set up the roads and intersections agentsets,, H% b$ ^: y3 P# y A5 w' k
;; and initialize the traffic lights to one setting
& F$ C& o5 V3 O6 A/ x- Oto setup-patches: X% ?' a. z5 T! u: U! L2 H
;; initialize the patch-owned variables and color the patches to a base-color
* h& ~, O+ ?$ l' M ask patches
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) { ?9 T& l+ Q" T: w5 g' m set intersection? false+ |+ C2 W- v4 H6 ~% f' q
set auto? false* H! w4 a* j8 n5 C. k
set green-light-up? true s \! Z+ X# ^9 U; j6 J
set my-row -1
# M& _7 N4 Z$ a6 w/ ^! x1 S set my-column -1) @; h; T4 i3 C" J6 z
set my-phase -1, H. A# r: I- {$ {0 x- t, W' f; c
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets. ?/ i8 u O, L, C
set roads patches with
. V9 K+ v" J2 Z4 ^$ b7 X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 |: F; E/ T- A. X (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 p! c6 T( k% h$ Q/ {. R
set intersections roads with, h7 d- h" E" k- G, T p, @& k" S
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and' X$ X9 ^0 m% _3 e
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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5 d2 T$ [9 f" y7 h, ]" e9 I" b ask roads [ set pcolor white ]
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end' A% j, E3 I+ S O
其中定义道路的句子,如下所示,是什么意思啊?, d$ H, ^- e2 I- Y( X
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; f$ B, L* O! a) \- j( w% t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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