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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。
$ ?' v: Q" K$ N! Q" c( Jnetlogo自带的social science--traffic grid这一例子当中,7 a$ l( v& F3 ~0 |+ K' u( X5 k
globals# E M. z2 a# h; Y! e
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9 C- W! L# ^1 g: _/ e* R grid-x-inc ;; the amount of patches in between two roads in the x direction- A4 d q F* y5 n( V5 K0 I" J4 b
grid-y-inc ;; the amount of patches in between two roads in the y direction& J) a1 H9 F) |
acceleration ;; the constant that controls how much a car speeds up or slows down by if6 m! w) v. n& E3 N( z# ]2 |: I
;; it is to accelerate or decelerate
+ e) G1 }5 }6 b/ R: { phase ;; keeps track of the phase9 W1 m- _' |$ [9 ]5 T, v6 M
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
% q! P" D1 t& K: a: | current-light ;; the currently selected light
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;; patch agentsets1 S! E7 ~- z: Q: c# i) L) E8 h, c
intersections ;; agentset containing the patches that are intersections
; T; ~$ U0 D) G, v9 b4 q: Z& f/ u roads ;; agentset containing the patches that are roads
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- a2 a. s3 Y+ E3 v7 uturtles-own& }1 E. w/ u; k. R9 f' |( z* X
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speed ;; the speed of the turtle, `- ]7 @# Z1 H C' u
up-car? ;; true if the turtle moves downwards and false if it moves to the right
: a) P6 s$ u1 a! ` wait-time ;; the amount of time since the last time a turtle has moved
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1 r5 w2 u6 }* |9 P6 s" R' d# Lpatches-own9 Y6 U& p& `3 q! Q ]# r1 Y4 }
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1 W7 H. j" c' i intersection? ;; true if the patch is at the intersection of two roads9 x' Z1 C# Z6 u, U4 c) T
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- { x" v' R9 {$ l# V4 m. @6 r ;; false for a non-intersection patches.
8 a; x' l8 M6 Q6 p6 o my-row ;; the row of the intersection counting from the upper left corner of the' b+ p* Z: N: @/ f' {- _
;; world. -1 for non-intersection patches.! Y- g' U" U8 H1 A9 x
my-column ;; the column of the intersection counting from the upper left corner of the
/ G& F9 K/ j8 N ;; world. -1 for non-intersection patches.
: e' n. F& G3 E6 x" F my-phase ;; the phase for the intersection. -1 for non-intersection patches.7 d- t, P" l$ C
auto? ;; whether or not this intersection will switch automatically.5 F5 U, r$ d9 f
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
2 a* E( \$ S0 B% {; p;; Setup Procedures ;;! O1 l5 z: D( u) I/ E
;;;;;;;;;;;;;;;;;;;;;; ~/ ]( h4 S" h3 l$ i( j
7 k5 m$ U$ H) H/ H;; Initialize the display by giving the global and patch variables initial values.8 Q8 e* _ L; j# U, u
;; Create num-cars of turtles if there are enough road patches for one turtle to
7 j, w# P7 Z: i7 F;; be created per road patch. Set up the plots.
, `4 {, _6 \2 J6 C# N$ Ito setup
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( G5 \% l5 n6 G. Z- u# ` setup-globals
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- b8 w4 k& c E( s9 w: { ;; First we ask the patches to draw themselves and set up a few variables) p7 f% I% ~5 [+ B9 x
setup-patches
) T# q9 `+ D$ a( o- u! K6 u make-current one-of intersections+ z- w- ^% r- E( t
label-current
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set-default-shape turtles "car": ^' y' n% _+ }3 g
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if (num-cars > count roads)
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( @; V* Z+ L* J$ D, ~8 l5 u user-message (word "There are too many cars for the amount of "
3 K2 t3 U. b, w }- P "road. Either increase the amount of roads "+ _# L% d( U5 N: D8 z
"by increasing the GRID-SIZE-X or "- M; K+ D1 D! @+ Q
"GRID-SIZE-Y sliders, or decrease the "
, R6 P+ [5 M9 |+ O& O$ v "number of cars by lowering the NUMBER slider.\n"( [ ^* d# z4 G. p% S7 S
"The setup has stopped.")
5 E% z% M' U' m z. [ stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color* O* Y( Z& k' y9 X3 v4 z
crt num-cars
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setup-cars0 ?( l! c! w. _- x* c8 |* N8 |
set-car-color
4 w' c2 j. x: f; n" Y: N record-data
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;; give the turtles an initial speed
3 C7 W$ m& u f6 M ask turtles [ set-car-speed ]
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; p. ~8 G1 Y6 T V3 X: t reset-ticks6 `1 D A+ c) Z: Z7 b
end) n! R3 q( `$ k) B# C
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;; Initialize the global variables to appropriate values
7 Y/ _/ \) j& P- \' N& V' g0 p9 ^& Qto setup-globals; o- T$ P$ n/ ~
set current-light nobody ;; just for now, since there are no lights yet) A7 l# O2 `+ h1 }
set phase 0
! W q: Z$ M- \ |, a' X, N set num-cars-stopped 0. t6 J$ Y$ V f) z
set grid-x-inc world-width / grid-size-x: i2 Y/ O+ R' l8 w
set grid-y-inc world-height / grid-size-y5 u5 x) @0 o5 y: z
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary! y$ R5 N. E2 V3 G2 n4 `+ _
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
6 O. l; E6 n. S& x;; and initialize the traffic lights to one setting' K* @* J" a% v& u- h( m b
to setup-patches
; I h0 S* i3 H$ O& q8 F; _ ;; initialize the patch-owned variables and color the patches to a base-color
$ m9 F+ \1 X4 H5 ^9 @ ask patches$ e* {( y: }' g* [8 V3 ]; P$ }
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set intersection? false
8 Q4 z' C1 i; }9 Z set auto? false
$ C b, l) g2 @; u1 J/ {' Z/ v4 p1 K set green-light-up? true" z! I9 ^) |# ]( y: o" `- `
set my-row -1' t0 Y0 h$ z! M$ m7 c; K! U
set my-column -1
3 Z. f: \3 O$ H/ {2 C' H; J$ U set my-phase -1
: a' \2 B- j) T/ Q8 Y7 m set pcolor brown + 36 L! g& l5 h, m! ~5 d6 T; I) b
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;; initialize the global variables that hold patch agentsets: O c, P- e2 |1 r: f, `2 O& t9 z! _9 F2 j
set roads patches with
+ i- O. g# z& `3 ?! W2 A4 R* M6 ]0 e% W [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or+ J: f$ ?5 g0 k7 W0 g. d( |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 H0 T& B% t; r: k7 R( z set intersections roads with% H9 F9 P& b# J- o& C' g
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and" X' v3 C* k) B. Q b
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 N. m- C8 d0 z; ? u
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ask roads [ set pcolor white ]
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2 Z. n& N: e) L: K其中定义道路的句子,如下所示,是什么意思啊?
0 Z6 T; [1 F5 U" m3 n) { set roads patches with
. f h; j. `1 A; R: u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. e4 n6 |4 u0 f' R/ U0 }$ R
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 {- @* t6 Q4 g) Y+ @# V# x! _
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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