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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。 E$ l; [! Y; E/ p% t
netlogo自带的social science--traffic grid这一例子当中,- ?+ b' V, ^1 j
globals
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( d( u- A0 T T& u$ i& N grid-x-inc ;; the amount of patches in between two roads in the x direction: ]6 Y3 J: S& Q2 ^6 x
grid-y-inc ;; the amount of patches in between two roads in the y direction" D4 a% l ~% V
acceleration ;; the constant that controls how much a car speeds up or slows down by if3 ^* d3 m+ V o$ Q" H$ g" ~9 u
;; it is to accelerate or decelerate
3 K& v+ E7 _7 i' r phase ;; keeps track of the phase( j7 F, m- S8 T$ u. M9 {# k n
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
: K( ?4 |3 I4 o, X1 k current-light ;; the currently selected light+ H/ [+ ~3 S" v4 X
+ h, d/ F- h) a1 x7 X" q: O
;; patch agentsets
( T P( O/ R0 Q5 |0 v& _ intersections ;; agentset containing the patches that are intersections+ h! |2 S$ B0 y
roads ;; agentset containing the patches that are roads2 W% M) o& c/ C1 O% B. ~7 X% U
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6 Y% m- G: o7 Z6 V% R5 I" Cturtles-own9 l1 V; r! D* g4 u6 v. I2 C. e; r
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+ D+ H, f. o) L# }5 y! o speed ;; the speed of the turtle
" \) c8 w+ m* t, C( y up-car? ;; true if the turtle moves downwards and false if it moves to the right+ D2 I# E0 W; g4 j2 o2 ]1 d
wait-time ;; the amount of time since the last time a turtle has moved2 U M7 b% G$ Z' v9 |6 D* ~
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patches-own, ]" Q- \) }0 N Z1 l
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( y5 t$ V8 S: V* ?4 j intersection? ;; true if the patch is at the intersection of two roads" i4 s+ Q$ y# l; r
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
0 F; B( F. A$ B3 g ;; false for a non-intersection patches. ^9 _0 v1 z" E8 k9 I* H& `
my-row ;; the row of the intersection counting from the upper left corner of the5 x" Q( o5 U1 M6 A7 f
;; world. -1 for non-intersection patches.
) o3 q2 ~3 S' ~4 y my-column ;; the column of the intersection counting from the upper left corner of the
9 T h* K$ K! p8 a ;; world. -1 for non-intersection patches." a. W' {2 E% E$ X- O3 j/ x
my-phase ;; the phase for the intersection. -1 for non-intersection patches.& B/ W3 H: E! Z p( `2 u
auto? ;; whether or not this intersection will switch automatically.
6 Q. l! A5 X1 U4 S: j/ j1 d ;; false for non-intersection patches.2 x- A/ Q& l7 Q
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;;;;;;;;;;;;;;;;;;;;;;
+ @& ?% w' Z- }' [0 M/ a4 c;; Setup Procedures ;;' e& f. j7 T8 {0 `& {0 z" O
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;; Initialize the display by giving the global and patch variables initial values., y8 M4 `( \: @& c
;; Create num-cars of turtles if there are enough road patches for one turtle to
. Z; n5 z" W' _# R1 f" {/ [/ x;; be created per road patch. Set up the plots.
5 p# I" J. F$ V S% y4 Nto setup' e' V& d& \4 T1 H' q$ J
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables9 K2 B& P/ @- Q* i" h1 f
setup-patches
3 i) a d# H- x make-current one-of intersections
8 M8 c3 W; m) l# H1 U3 @3 l* y label-current0 c5 ^0 l6 D' S J
) H; z4 X/ ^. k. }# @ set-default-shape turtles "car"; W+ j+ z- o7 z& e" `
0 Y" X+ l1 M: ^% Q8 z0 B if (num-cars > count roads)
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% `/ N6 [# d8 Q9 b& ^- u user-message (word "There are too many cars for the amount of "
2 g& z; p! q2 U$ W "road. Either increase the amount of roads "
& D# Y2 N- ~9 x "by increasing the GRID-SIZE-X or "
% Y' `' ~7 Q( W/ | "GRID-SIZE-Y sliders, or decrease the "
% X+ t+ T, W: U# q: h- P "number of cars by lowering the NUMBER slider.\n"/ y& r7 c1 x' k
"The setup has stopped.")6 n9 Z* l' V6 o7 f# d
stop
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4 i1 d ]2 ~6 E1 d; } G ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
$ e8 T8 N& n8 ]: |2 t) i crt num-cars U9 C9 A9 P8 q( r" ~1 k7 A/ O
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setup-cars
6 E9 I7 A/ J {9 s2 q set-car-color
& Z. R( M4 x. M0 ` record-data# f% T5 H w, l, t; G3 f
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;; give the turtles an initial speed
; M# l/ L% f( L6 l4 U& Z+ s ask turtles [ set-car-speed ]/ ]& f/ Y5 D* s Q0 L
% n; ?2 b$ j. [+ s4 T reset-ticks
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;; Initialize the global variables to appropriate values
% l% C( G+ ]4 `7 Qto setup-globals1 d! N" r) E* j/ k" Y4 f& g5 }7 }8 K- G
set current-light nobody ;; just for now, since there are no lights yet# d+ k6 J" y" |8 G9 q
set phase 06 Y6 d+ s2 j. \: _; N( E/ l
set num-cars-stopped 04 ?) ]8 J: f& u% t9 P2 \
set grid-x-inc world-width / grid-size-x
$ {& E, q0 F6 }$ w' f8 V/ ^2 u [: b set grid-y-inc world-height / grid-size-y
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- P* t* Q0 Z, U) N( `4 m$ e4 ^3 x ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary! h* W6 L. N4 ]
set acceleration 0.099
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" l; w3 U% v8 x;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' y0 N3 j2 D- J3 _* E$ ^4 Q: O;; and initialize the traffic lights to one setting
! m! E1 Q. s7 t8 ~to setup-patches2 ?4 C( E& [: M" l, R, k A
;; initialize the patch-owned variables and color the patches to a base-color
' J/ t0 ]4 R( @: K7 F ask patches0 P3 C+ e) b0 m7 q# V
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0 b. W( {. @: r: S set intersection? false
. T0 {: v( h9 [( l2 h5 O n set auto? false# c% z6 B( N. i, s1 ]
set green-light-up? true
' v7 g* ~% V" |" D set my-row -1
/ T" K3 G4 v6 x/ F3 O& |- k' {0 K set my-column -1. M8 |, g" a* I: z9 K
set my-phase -1
7 n4 q3 @' k) ?5 r set pcolor brown + 3. O% }, f) |7 O. B
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;; initialize the global variables that hold patch agentsets
+ D$ ^- @# u2 A5 v- [ l set roads patches with$ F; @: G" d0 u0 v D1 Z( b. S
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& [& s* b; ?7 K- e) i3 | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* r" ?& {- H$ {# F5 U* R/ Q0 E set intersections roads with
& q4 N, Q; z6 A' h) M- m* a* Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and: N" }% q% M& r1 |6 Z2 ?
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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. @: L* n. n. {+ M3 Y ask roads [ set pcolor white ]
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end
3 l0 I3 G) U% `5 J5 {* O* t其中定义道路的句子,如下所示,是什么意思啊?' s- K/ X5 G. _( Y% j& L
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]) D; ?4 E3 ^3 A2 \; n
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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