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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 e; e0 [+ G0 \6 }2 f+ m
netlogo自带的social science--traffic grid这一例子当中,
$ a0 X; @ @/ \& Eglobals" H: T. \9 G; G8 c2 k
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grid-x-inc ;; the amount of patches in between two roads in the x direction0 `2 k/ A: r! ^& w8 M
grid-y-inc ;; the amount of patches in between two roads in the y direction
8 e5 E6 o3 R: _ acceleration ;; the constant that controls how much a car speeds up or slows down by if: f: f+ d% b- K% ?, T; X) h
;; it is to accelerate or decelerate
/ x- f" x0 U+ |* i, \0 o/ t phase ;; keeps track of the phase6 O Q$ w' u; P% a! B9 u
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure( b$ O% N* y e+ z
current-light ;; the currently selected light4 I' G% u: B$ c* I' h* D
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;; patch agentsets/ K0 F; s0 {. x& z9 I+ f
intersections ;; agentset containing the patches that are intersections, B5 ]4 N* F# |; ]+ t* u6 v7 m+ A
roads ;; agentset containing the patches that are roads4 {7 g/ m) B( n3 r+ l! a G
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turtles-own
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0 l' u) ~( P( C. [( x speed ;; the speed of the turtle( j8 `1 a- ?9 u7 I4 ], ^
up-car? ;; true if the turtle moves downwards and false if it moves to the right- k U0 z- [% F. Z( d& S8 h7 G
wait-time ;; the amount of time since the last time a turtle has moved6 ]1 X2 G# d! N) H1 m- ?
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patches-own& K/ Y8 a( x( `% h1 d. ~! I
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3 P0 l* q% x2 K4 M u. j* V" N intersection? ;; true if the patch is at the intersection of two roads" w) L) r' ?; U+ N0 u) D4 b% ?
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
# d* [( h( `0 u* a ;; false for a non-intersection patches./ g" t) j5 x: o! ]9 C
my-row ;; the row of the intersection counting from the upper left corner of the
4 ~/ q& t& Z2 L0 u- B' S0 L ;; world. -1 for non-intersection patches.( {0 O1 u U8 h3 ?) r' ]2 e
my-column ;; the column of the intersection counting from the upper left corner of the* G0 s/ j5 [3 b6 i1 X3 V5 Z4 ]1 Z
;; world. -1 for non-intersection patches.- |- _+ o5 u+ p2 Y7 ^3 k$ F
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
# R$ b' w3 w" D2 u0 Z" V9 G/ l auto? ;; whether or not this intersection will switch automatically.6 q& x( I( l' y3 K( L/ z
;; false for non-intersection patches.
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- w, m( E/ r3 ~& K) K;;;;;;;;;;;;;;;;;;;;;;
& g; N3 A6 N' h/ o! ?; c;; Setup Procedures ;;
+ X P/ P9 j2 z9 a4 |% K" k7 T! Q o;;;;;;;;;;;;;;;;;;;;;;) L' U0 i1 q) ?& |0 \! ^6 q
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;; Initialize the display by giving the global and patch variables initial values.
0 ?5 D3 L$ L1 N( a2 `;; Create num-cars of turtles if there are enough road patches for one turtle to
" J& F" c. ]: G& M;; be created per road patch. Set up the plots.
$ Y, G% I# e8 j( r+ v) D. zto setup8 |1 y4 O# [* T5 N+ l8 d" p
ca
; R }! ]1 a! [& b! y; T setup-globals/ a) _8 M, q1 o+ ^6 D( B
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;; First we ask the patches to draw themselves and set up a few variables
3 ^; c# F7 f! z: @ setup-patches9 ]+ h8 X' v- k( ^6 ]
make-current one-of intersections
9 X% z! V3 x! t label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)
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1 _8 L& i- V. I: n5 x+ P1 w/ I user-message (word "There are too many cars for the amount of "8 D% W4 u- n( b- w8 S* P$ u
"road. Either increase the amount of roads "
* @4 Y# b! _/ o% E: m "by increasing the GRID-SIZE-X or "/ N* p) F# T' a7 T, g/ B$ o
"GRID-SIZE-Y sliders, or decrease the "
* d0 v. O* C* } "number of cars by lowering the NUMBER slider.\n"
6 S! H$ J) W U2 C3 J5 e "The setup has stopped.")* a+ ? D( i |
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color3 w8 w8 k' }9 N
crt num-cars- N, G: h9 Z2 r8 d
[, w8 ?& G! M5 ~3 U# u; J
setup-cars# \- c" [2 Z* l, h" G) S
set-car-color
* s* y+ \) Z( Z: G record-data+ C. x+ H! {/ g" o5 Q2 O2 W4 N% O, q
]
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;; give the turtles an initial speed4 V2 ?* K9 p4 t' z
ask turtles [ set-car-speed ]
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2 s) S; X0 i$ v0 z9 \4 ? reset-ticks
1 v6 _, x& b* i6 T! i: w. @1 Tend& F! [4 g3 x* C! ?
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;; Initialize the global variables to appropriate values) N: Q; \5 T( t4 K8 e
to setup-globals
6 k2 S. B$ [3 g7 L, u set current-light nobody ;; just for now, since there are no lights yet' m$ ?0 V* D$ v2 s! F. X
set phase 08 Q. G/ L) Q v4 f7 v8 q
set num-cars-stopped 0
( C3 _) T) ^- r; h$ B8 J set grid-x-inc world-width / grid-size-x
5 G* E" A+ K. S! x- m7 n9 | set grid-y-inc world-height / grid-size-y& W- R* K' X" U2 ~' L5 Y! j
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary; B; M0 A! v& o# d6 _
set acceleration 0.099
$ \9 e9 l# B; q9 l+ B send
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
$ M. }* o+ p4 Z: n1 F, G" |;; and initialize the traffic lights to one setting" F+ _0 F! ~( z/ O( f- z
to setup-patches" y6 o4 e/ i. W* W, _- L
;; initialize the patch-owned variables and color the patches to a base-color) |- t( d2 L: k" z
ask patches' ^" e# U# W" W" y. T" S, s! ^
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set intersection? false! w6 n% U, }0 s% u
set auto? false
: B* M! D$ |$ G set green-light-up? true4 t& O* m3 Z7 V( L( ~, ~) f
set my-row -1; a% n5 d/ Y1 I& A& \
set my-column -1
2 q3 B, Q8 z2 ]7 O1 `! f! J set my-phase -1) w/ [) J+ J8 L" w3 C
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
/ v& C9 t9 E0 G0 G# p set roads patches with
9 G: |! e( j) A" ^: `3 S+ x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& n3 y; o( g8 H+ V3 O0 a* a (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 x( K g3 \( O2 r/ I9 W7 G6 @ T
set intersections roads with: O |; U; `, V( w
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
. W5 I; q* F2 o (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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8 ], x$ F& q8 A3 u( A ask roads [ set pcolor white ]. H2 G" W$ H, e
setup-intersections( G3 H6 A( h L
end
; N% S6 j1 Z% v) a* A# L其中定义道路的句子,如下所示,是什么意思啊?+ |4 h8 q" |8 F3 u$ ?- I; c0 F' D
set roads patches with; R0 W v W5 X$ M/ A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ Y, S) V/ U7 P, O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]" \( [! K+ a2 Z- w7 k' \, P4 z
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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