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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。
2 \) H2 ^9 K/ E% v ~/ Ynetlogo自带的social science--traffic grid这一例子当中, z/ A* W4 z8 h# t$ E
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
& R0 r& y; p8 x7 b' B1 p. z+ X. ]5 v4 g grid-y-inc ;; the amount of patches in between two roads in the y direction
4 e( e9 m( m; O. e acceleration ;; the constant that controls how much a car speeds up or slows down by if; {% D& r0 z/ |: ~1 X1 ~: }1 ~6 @
;; it is to accelerate or decelerate
; W$ f- m8 n. X* s phase ;; keeps track of the phase2 |4 n5 p& d2 z2 E$ `
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" a4 C3 c! P- p2 ~# B
current-light ;; the currently selected light4 n6 h+ x, E( [+ B
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;; patch agentsets
3 g' w6 S8 X8 |6 I intersections ;; agentset containing the patches that are intersections% q# a7 `1 t0 D) {+ D
roads ;; agentset containing the patches that are roads) O( A5 v; ~ S9 V. D3 Y) ]2 {
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1 \* U. z Y0 E; E Dturtles-own) k% N( o9 r. H* P6 s% K! J
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4 R5 o2 d0 \! A n. Z. y2 W( _ speed ;; the speed of the turtle4 w. v5 Y- B/ n7 L$ n1 L2 s
up-car? ;; true if the turtle moves downwards and false if it moves to the right4 G, f e1 R: C& z# S; ~% u; d' F
wait-time ;; the amount of time since the last time a turtle has moved
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) N9 x Z+ q: Q- v9 _: f' opatches-own5 O9 ^" s8 z6 W
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/ I/ C N/ y. r& ` intersection? ;; true if the patch is at the intersection of two roads x1 [1 e; ]# |# `: v9 G8 s# B5 T
green-light-up? ;; true if the green light is above the intersection. otherwise, false.7 k+ Q4 A& I1 y/ }. j2 D1 {+ ^# F
;; false for a non-intersection patches.. B. Q' k. A- R6 e: a
my-row ;; the row of the intersection counting from the upper left corner of the3 g; p9 [" o) F+ L( K1 d$ P
;; world. -1 for non-intersection patches.
+ z2 q5 u3 [8 ~& G! K; f my-column ;; the column of the intersection counting from the upper left corner of the
* G( ^) i6 o! Y8 P3 q3 c* p6 O ;; world. -1 for non-intersection patches.) o; A! q( a. E& l8 N
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
1 ~$ v3 n! I3 H. r1 Z4 p5 I: s auto? ;; whether or not this intersection will switch automatically.1 h) U; Z# M( J; `; E
;; false for non-intersection patches.( A4 P1 o2 [! b4 t7 e, V6 O
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;;;;;;;;;;;;;;;;;;;;;;
; i& u- U0 b6 |/ H1 @$ F/ `3 w;; Setup Procedures ;;4 C& a$ ? [% _. S3 J2 \ Y2 F
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, }4 r* ?" ^; S; c;; Initialize the display by giving the global and patch variables initial values.
# q0 a0 J1 P. p) Z;; Create num-cars of turtles if there are enough road patches for one turtle to
* S5 J; \0 M/ [;; be created per road patch. Set up the plots.
9 ]. H4 `" d0 n4 o5 x0 ^to setup! O& o5 ~* ]" ?) W* v M
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
* P+ e. N$ n$ y1 B# g9 s setup-patches
. R; \4 n' j" L) U/ m make-current one-of intersections0 D$ k# [4 `" l. X% g* H
label-current8 i G1 L% [ b
/ y1 G7 f8 R, ~: M. `9 ]/ y set-default-shape turtles "car"
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if (num-cars > count roads)" ?' p8 ~. b- F8 k9 l( U1 c
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user-message (word "There are too many cars for the amount of "1 x D& K" ~# \4 I
"road. Either increase the amount of roads "% K1 b7 H8 D6 A- f) Y
"by increasing the GRID-SIZE-X or "
7 P/ w' }) D1 i7 B "GRID-SIZE-Y sliders, or decrease the "
4 P5 e& Z' X, T8 k1 ] "number of cars by lowering the NUMBER slider.\n"
. s5 |2 W5 @6 d/ ~0 d; L! H; ]8 i6 N. L "The setup has stopped.")
0 P# Y3 b& l6 c stop
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3 t3 L! U k! l6 K$ p ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 O7 G2 H# \/ Z7 i crt num-cars
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+ {( g% Y9 s3 w0 k setup-cars
M3 |6 t! |+ i( Y( |9 _# A, l set-car-color
% z9 D% H+ T! J. l record-data3 R! U3 P! a! W8 R7 `/ P
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;; give the turtles an initial speed
5 g: d" |5 L! H: S& e; G ask turtles [ set-car-speed ]4 k! |! M$ Z5 D
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reset-ticks
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, g& J. r, o* M1 {) h6 Z;; Initialize the global variables to appropriate values4 J, l& z$ G% }* t6 g P1 O% `
to setup-globals2 m: l: _9 d; R" R9 R3 ]4 p2 O F
set current-light nobody ;; just for now, since there are no lights yet
" U# e! u* F) q' T set phase 07 A) \3 ^2 C) x& j8 `! S/ m. R
set num-cars-stopped 0/ O" |2 g- k9 n6 j# I
set grid-x-inc world-width / grid-size-x
8 H4 ?) I8 U0 F1 ~4 [9 ? 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 boundary4 S, X% N3 J& V8 X& t
set acceleration 0.099
W0 L# m) Z K; O0 jend
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' {7 W* @% t, C* |9 y( F( S$ e;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
* x! S* E0 M. ]6 Y) T;; and initialize the traffic lights to one setting. D' z# g9 d% e& i! f- z
to setup-patches) H1 s0 p+ `4 Y6 S t" Y- ]
;; initialize the patch-owned variables and color the patches to a base-color
! ]" F. ?/ r0 b& n/ l ask patches( p9 Y1 f) q% D* i$ ?
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2 s! p- [# T2 g2 U0 p set intersection? false
" c2 {( ]& o! B b# i set auto? false$ w3 U3 ^) ^) J% J* O' M3 A
set green-light-up? true
* Y3 d6 `' p% Y set my-row -1
/ G' F/ y8 ^ n" f# I set my-column -1
; R: g1 y: [; g8 J/ g! F0 H set my-phase -1
, a, g! g- _3 j2 x* X7 j' O$ b b4 O2 ^ set pcolor brown + 3# k6 Z ?0 f6 S, H' h* ~
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;; initialize the global variables that hold patch agentsets
# l# K, N$ G% T9 m set roads patches with
5 \7 p' T# S; J" ?4 h9 r. N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& R2 J9 y; B# u (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; ]# O5 N, i9 x( Z
set intersections roads with
1 p- u& V$ f' U8 c: M% y* z) Z+ b5 B [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( h2 m8 l5 d/ o, t9 ?5 S1 B
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 p% n$ A7 [2 }: M: \: i- ^
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ask roads [ set pcolor white ]5 g5 ~% P3 K: K/ ?" p0 u# | }
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?3 k, e ^! P* p# b( K" H
set roads patches with8 L4 _! F! H9 N E" z" o4 q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) \5 T8 S; `1 M4 R- i$ h8 \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ Z6 n) L8 e6 \" Y' {
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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