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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/ k6 t4 q! }: ]. q1 a7 m9 Ynetlogo自带的social science--traffic grid这一例子当中, Q( M8 |8 \9 N& c; r- O
globals
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) F! k2 | w. b% ?. C( Y1 s grid-x-inc ;; the amount of patches in between two roads in the x direction) d$ T. y3 A# { A: M+ ^/ n4 z
grid-y-inc ;; the amount of patches in between two roads in the y direction
D* X* r! E( X5 A& ? acceleration ;; the constant that controls how much a car speeds up or slows down by if
+ P, P+ a# ?. ]9 r ;; it is to accelerate or decelerate
+ H d6 o2 \1 v0 L. I phase ;; keeps track of the phase
6 Z) o) l$ E) j num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure1 D; p& h' Y7 b# D3 m1 ~6 N
current-light ;; the currently selected light
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;; patch agentsets c' a2 m P0 T+ b- c% O# k
intersections ;; agentset containing the patches that are intersections. w; M. X% ]+ m0 U
roads ;; agentset containing the patches that are roads. t/ O C& _7 f8 [% D0 p7 D
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6 ]/ m2 v i: V t% X4 F0 X, |turtles-own! G' S$ W* K3 J7 J$ ?
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speed ;; the speed of the turtle6 o& j7 e5 F' U7 z
up-car? ;; true if the turtle moves downwards and false if it moves to the right
, x C' z! h0 G. v wait-time ;; the amount of time since the last time a turtle has moved" j: b" f) R4 D6 ^: K# j% E# E
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patches-own
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: m! n9 c* n3 R2 K/ _8 w intersection? ;; true if the patch is at the intersection of two roads
. L9 @% [ B$ G- V0 U green-light-up? ;; true if the green light is above the intersection. otherwise, false.- n* z2 q2 h. R
;; false for a non-intersection patches.
% B/ [) Z# X) g4 ^0 p my-row ;; the row of the intersection counting from the upper left corner of the5 F+ K A" G# V5 Y, Z
;; world. -1 for non-intersection patches.
- L/ i1 H' W) f& @* [- s* c my-column ;; the column of the intersection counting from the upper left corner of the/ v) M6 ~, V1 G, o; z' S' P
;; world. -1 for non-intersection patches.
' |1 M, O. _' J$ ~$ j0 T* I my-phase ;; the phase for the intersection. -1 for non-intersection patches.
3 H( r- W" w( r. `3 W4 t1 [7 ]1 b auto? ;; whether or not this intersection will switch automatically.& R9 Q1 w+ N6 U3 e: i F+ e
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;6 Z! c9 M1 T& @. g1 W3 m
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.
- ]1 ^! Q# |! g: ~5 _/ g;; Create num-cars of turtles if there are enough road patches for one turtle to' A, `" N1 K+ P( Q1 n
;; be created per road patch. Set up the plots.
8 K. S, u1 Q e( Yto setup
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setup-globals4 l3 f' g/ c4 S5 @
. v; {+ y9 I! A ;; First we ask the patches to draw themselves and set up a few variables
3 W# J/ {5 M- h8 o5 ^7 O2 l) } setup-patches
1 w8 Z1 F, i% B9 @/ L make-current one-of intersections
2 U: }* {7 H7 ]* e( _: ?6 _ label-current
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1 P9 J Q' {2 m% ^: J* C( Y set-default-shape turtles "car"
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) j/ P4 Z k1 s0 B0 `! Z5 U if (num-cars > count roads)! C' |) x9 L$ G0 w" y
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user-message (word "There are too many cars for the amount of "
$ ] H5 e6 ]0 Y% S "road. Either increase the amount of roads "
% c6 { i8 I1 y "by increasing the GRID-SIZE-X or "/ u; H% M: y! Z7 x, z$ I( W
"GRID-SIZE-Y sliders, or decrease the " |! m7 |) z8 ], L% |0 j
"number of cars by lowering the NUMBER slider.\n"$ L; g3 E2 u. e$ A- u$ r
"The setup has stopped.")( e, S# v" c& b7 ~8 l* ]
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 J7 ~* i( R3 x6 G2 c) x' ^ w crt num-cars
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7 z5 u% ^2 x2 s$ D setup-cars
5 I* u1 m( b( g- K2 J+ Z set-car-color2 @' ]; C( C# Y9 h$ z' W7 w
record-data
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;; give the turtles an initial speed4 u# a; u+ b, M
ask turtles [ set-car-speed ]
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reset-ticks
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% |. [: K6 M" d6 }( C) q: a# \;; Initialize the global variables to appropriate values
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K) s! I/ h2 g' F, w set current-light nobody ;; just for now, since there are no lights yet& l$ [( ~- ~/ ~. k
set phase 0
5 P# _. ]' v' z: [ set num-cars-stopped 0" J, f: |* t3 t% W5 a
set grid-x-inc world-width / grid-size-x
( Q V, U9 ~, l" k2 @3 d 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 boundary$ S! m+ e3 u" E6 f. V
set acceleration 0.099
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5 h* c' G5 x& W;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 r9 j% D9 c5 n/ T* A# O
;; and initialize the traffic lights to one setting
$ y8 S9 d) v: ?- r, A3 `+ [to setup-patches
- W0 a) t" |- G6 T* W& \ ;; initialize the patch-owned variables and color the patches to a base-color
8 p- U) J6 \8 ^ I7 H ask patches" ^* g8 X7 Q6 X9 }
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, Z% ?: L; b' K5 |) r. t/ q- q5 U set intersection? false) G" q$ }, {! k. |6 z: J* [
set auto? false% F; c. `$ B1 Y( q0 d! _# ~5 q
set green-light-up? true( v0 B3 \* ]: h6 v& z
set my-row -1/ y$ |# a# y, A' t$ ^1 ^3 n! ?/ y# R
set my-column -15 _8 Q+ M# H6 A) a
set my-phase -1
}1 _: j3 E: s' E' F set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets& I7 s/ B$ ^% v6 B5 {% p
set roads patches with0 H2 x1 [ l. R4 i
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* E% P( k8 j1 C% Y+ U: V4 n3 A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 G5 e. W+ j' }* c
set intersections roads with- w% ^# Q( V d; P. l- C% P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and C* g9 b2 X) U" @9 L) B
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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7 F% j- N& z5 W) ]7 k% L, u7 ^ ask roads [ set pcolor white ] S$ r3 M1 [$ R3 r
setup-intersections. Q5 h6 W; n, r$ J& f
end
\. f7 d) r2 Y1 |$ @: ~其中定义道路的句子,如下所示,是什么意思啊?* S1 ?0 u3 r3 f7 K+ |" s+ k5 k; G
set roads patches with' A5 {4 X/ S0 k- K# k
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or! J2 j1 G) _* R! R5 h( V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]' [1 z7 `, D- T! M M: 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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