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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。
( p; Q; _' v' J4 Y1 inetlogo自带的social science--traffic grid这一例子当中,
: ?2 Z- }! S" t" \' x% w7 }globals
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( { d t+ @4 N! r) D ]; f$ p4 | grid-x-inc ;; the amount of patches in between two roads in the x direction
. o9 L$ L4 ^/ K3 h. H4 J grid-y-inc ;; the amount of patches in between two roads in the y direction8 o. l1 r% ]8 ~0 ]! x6 _
acceleration ;; the constant that controls how much a car speeds up or slows down by if8 P m- k. I: _; }& E6 B9 ?
;; it is to accelerate or decelerate+ H- D: g+ \8 x* W& k. ^/ b( ^
phase ;; keeps track of the phase/ M$ [: {; S# C" p1 H* @; E
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure% y' p9 R/ n. J& o( C* E
current-light ;; the currently selected light
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3 g H# r4 m& {1 K$ u ;; patch agentsets
: \5 ` {2 e V6 a intersections ;; agentset containing the patches that are intersections
# m) S$ [3 C4 N( u2 i roads ;; agentset containing the patches that are roads
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3 O# |1 w4 K7 g3 u, \4 pturtles-own5 `9 m( p8 ]$ a9 W. a( c5 R) y
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) D- S9 C3 a1 _4 n: A speed ;; the speed of the turtle+ h9 a+ S1 L& I
up-car? ;; true if the turtle moves downwards and false if it moves to the right5 C* }8 J+ U/ y' D; z
wait-time ;; the amount of time since the last time a turtle has moved5 n3 U; I% \( D' [( O1 U
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads) g# e6 A, Z8 X# u$ y, b
green-light-up? ;; true if the green light is above the intersection. otherwise, false.. d2 B8 Y# T9 d1 Q! _1 g4 n# S
;; false for a non-intersection patches.
; y, F% R0 `6 F+ e! R my-row ;; the row of the intersection counting from the upper left corner of the
" u& K1 H' H. g7 p ;; world. -1 for non-intersection patches.
! e- y4 d5 M' f/ }1 @7 ^ my-column ;; the column of the intersection counting from the upper left corner of the
) h) J _& p6 {: A/ P( u9 ? ;; world. -1 for non-intersection patches.
0 r! X& b8 T/ }) e9 u my-phase ;; the phase for the intersection. -1 for non-intersection patches.
/ G8 k: ]8 B+ t auto? ;; whether or not this intersection will switch automatically.
) w% y0 K9 V6 Z ;; false for non-intersection patches.5 o# D/ O# p6 \6 U1 j1 d4 D
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;;;;;;;;;;;;;;;;;;;;;;
5 [. E% C6 `, K* n;; Setup Procedures ;;
% }4 ^! f6 c! Q6 S2 L R2 Z;;;;;;;;;;;;;;;;;;;;;;) O f/ i) a4 u I- k; ^
1 a* f ^- o* t2 Q) m;; Initialize the display by giving the global and patch variables initial values.
3 ~* q- v1 k- k; T) M- t* \;; Create num-cars of turtles if there are enough road patches for one turtle to
9 }) ?: c5 m; ]6 Q; R; @;; be created per road patch. Set up the plots.
' I: X s7 F3 T0 F1 Fto setup2 K) I9 E% u1 N2 p. z: v. N. `
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setup-globals) Q( x6 o x4 Y; m0 `# }# D X: |
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;; First we ask the patches to draw themselves and set up a few variables
5 m$ V( [4 G/ s$ g/ y. o3 S setup-patches1 I. } @$ Z. Z, a& \0 y
make-current one-of intersections |4 @+ L s2 u/ H1 E
label-current
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set-default-shape turtles "car"& j1 T8 I" A0 z# X* k+ _2 G
, c& {2 l/ d' U Z4 q- X if (num-cars > count roads), k3 K2 A" R1 d
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user-message (word "There are too many cars for the amount of "5 [9 M4 Q1 }4 c/ K+ {! r6 E
"road. Either increase the amount of roads "( O: m6 W9 {, u9 ?& ^0 ~
"by increasing the GRID-SIZE-X or ". v- H8 ?+ K4 f& a0 F- I8 y; a
"GRID-SIZE-Y sliders, or decrease the "
5 E: f; w# o6 ~1 X( B "number of cars by lowering the NUMBER slider.\n"7 N% J: A$ p4 c. |9 w e
"The setup has stopped.")4 o) z6 C7 o; l7 ]1 Y
stop8 N0 ]& K( ^% w2 y6 Q* F
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5 d i8 L0 M; s% A' o0 D ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
' Y4 w, f8 E$ C crt num-cars; B6 x- V ^7 G7 c9 U8 | l9 F
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setup-cars
$ s( R& X0 R* _( P0 e, G- A5 V* a set-car-color
- B8 {- P$ l7 w' t7 t" e record-data9 c) d! o5 @( Z/ |# h
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% b* @6 O7 ?; X n3 l5 t ;; give the turtles an initial speed
$ X8 A$ y, j+ b. R# p8 |' p5 B' ?% w ask turtles [ set-car-speed ]
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reset-ticks0 w' C$ D- g. b. Z/ B# R
end4 |! X* P5 Z( A' H5 t: j% u
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;; Initialize the global variables to appropriate values
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. b; @, d, n& N0 _1 | set current-light nobody ;; just for now, since there are no lights yet1 a( J; Z5 e2 C% \3 v+ ]! f
set phase 0
) G c, Q0 A+ K0 f set num-cars-stopped 08 j& D4 E* R- s4 L. U! b7 ?4 i
set grid-x-inc world-width / grid-size-x1 F, a* I& u4 S3 W( h( v
set grid-y-inc world-height / grid-size-y; E2 ^# a% d. t6 U6 Q" f& p! @4 k/ d
1 k' M% {+ x% h5 a. }; t" M ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
5 [% ~" M# B6 e8 q3 O# _ set acceleration 0.099; y) U1 {3 [+ z# o( d
end
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4 Y. |, S$ G) i A/ H;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
, } L- } Y2 Q4 ?7 U* E;; and initialize the traffic lights to one setting
$ w2 R3 K3 m: G7 cto setup-patches: s8 o3 q" T4 |: k5 z
;; initialize the patch-owned variables and color the patches to a base-color* ]$ z* ~' V: ]0 O i& @/ S
ask patches9 k; U9 j5 g+ @6 E+ t" @; u
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set intersection? false
' E$ [7 V2 D# E set auto? false- \) b: s: K/ j" ?2 F; U( O" N+ c
set green-light-up? true
8 h: m( _1 X. g" q5 p2 d set my-row -1* N/ V/ H, R( a- M# o
set my-column -1: b0 A# F3 k; d: p! `3 X4 W
set my-phase -16 G2 B; U( D% v9 Y7 ~4 g0 p
set pcolor brown + 3/ Z9 M: @6 B: E1 w8 m. ^0 Z. I
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% h; I& Q5 }0 g, K ;; initialize the global variables that hold patch agentsets
2 K( d0 h9 l7 w" b$ }$ b# y. K set roads patches with
, `; v% \2 i9 i$ o/ u" w5 u& L; k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% O( b3 k1 g& B5 I$ S. g: y" m6 { (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, A( k0 F: h* E" |9 y4 B. Y, A set intersections roads with
* _8 j6 |: U4 S, v- S+ J# w; I [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" R3 N4 m( _4 a% a (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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其中定义道路的句子,如下所示,是什么意思啊?
6 ]$ @. n! ]8 s+ n set roads patches with4 g; v8 N4 X2 T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: ` B: y" V- [& Y6 f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ q4 T5 z: e( 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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