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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。
( T! _$ \8 B) y( Dnetlogo自带的social science--traffic grid这一例子当中,) U4 b! b. `3 M; N0 k& P1 |
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
- Q* W+ z, K) }& ~' r! t$ L grid-y-inc ;; the amount of patches in between two roads in the y direction
. A7 i% ~! B2 A+ `3 p acceleration ;; the constant that controls how much a car speeds up or slows down by if' y6 m1 D* B6 X) U* M
;; it is to accelerate or decelerate6 ~& i% u7 ?) }- A
phase ;; keeps track of the phase1 T2 h5 Q/ ~/ J8 R3 s
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
; I8 J8 B, N$ t1 x" ] current-light ;; the currently selected light( f# N* h; ~- K; Z" d5 t6 I
1 p) j* R/ W! L: D ;; patch agentsets
; `, a1 R" Z, D' P intersections ;; agentset containing the patches that are intersections; e. y8 @$ H$ m6 u
roads ;; agentset containing the patches that are roads
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) _5 E; ]# m: m6 ?7 cturtles-own
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speed ;; the speed of the turtle9 p4 i* b% x7 ^; }# v
up-car? ;; true if the turtle moves downwards and false if it moves to the right8 M3 a- ]& T; N) ?4 F( Q1 c
wait-time ;; the amount of time since the last time a turtle has moved
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; ^1 z# i/ V' u* v9 Spatches-own
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" S6 }; f( t- x8 e( s: y7 B- @ intersection? ;; true if the patch is at the intersection of two roads0 j" k& l/ G" g; J0 l0 ~
green-light-up? ;; true if the green light is above the intersection. otherwise, false.- h+ |& y4 V x0 n
;; false for a non-intersection patches.
2 Y5 t1 h9 D0 g, _% O) T( g$ B. K my-row ;; the row of the intersection counting from the upper left corner of the
3 M: }& Z; j$ t2 Z3 V ;; world. -1 for non-intersection patches., g9 G* U& D d8 q
my-column ;; the column of the intersection counting from the upper left corner of the
, y8 ?2 E2 K/ o ;; world. -1 for non-intersection patches.
5 [8 z1 Z" l6 ?( R$ R6 K my-phase ;; the phase for the intersection. -1 for non-intersection patches.
# z# V- ?: i; A ~; D auto? ;; whether or not this intersection will switch automatically.
8 e. i: X! ]9 h0 G# a ;; false for non-intersection patches.8 f8 a. K0 Q: o& W$ X2 e
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;;;;;;;;;;;;;;;;;;;;;;
% k) n" F1 k# f7 v: G/ v;; Setup Procedures ;;
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' {9 k2 ?1 I* Y0 e;; Initialize the display by giving the global and patch variables initial values.
1 W8 \) u. R% q$ Z/ G6 U" Z* b- l;; Create num-cars of turtles if there are enough road patches for one turtle to i* M* U1 |6 _6 E9 I9 q) u6 _
;; be created per road patch. Set up the plots.$ M5 k7 G3 b6 U' a& P& T
to setup6 U' L9 `! j; r: W% x6 W
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setup-globals: [3 k& P* Y L' Y7 t) k: r
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;; First we ask the patches to draw themselves and set up a few variables
0 w; V, R' L& P9 ^ setup-patches
! v" q P* p% ^" }( E make-current one-of intersections, l7 d o2 O1 E# Z! ?4 N- z
label-current
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set-default-shape turtles "car"
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& b' e; h1 k# Z! A# s( s3 } if (num-cars > count roads)
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+ @2 L' a' {2 D user-message (word "There are too many cars for the amount of "+ ?/ T$ z* j/ h3 N( b) e$ C% M/ I( |
"road. Either increase the amount of roads ") W( z$ J7 [. S' T9 B2 x+ T
"by increasing the GRID-SIZE-X or "
! N# V1 ]: x( O "GRID-SIZE-Y sliders, or decrease the "
1 w! l8 O3 x k7 Z "number of cars by lowering the NUMBER slider.\n"
& i( A/ Y0 e& p3 s k "The setup has stopped.")3 H" ^5 V g( T* {, a
stop2 N0 j, Q1 R) I
]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color* D; J" k8 `9 P$ p" P3 G
crt num-cars
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, T- u0 ?% k, j4 A/ D7 Z# ~ setup-cars; E1 W, T) O G& f3 K: _ _4 G# ~8 R) t
set-car-color
& Q; J4 q1 m$ f) |+ P. @! f8 E record-data
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;; give the turtles an initial speed( ~* A1 ^4 d1 j2 w: ]
ask turtles [ set-car-speed ]( k" a5 K5 f2 `1 g; {" T
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reset-ticks# i! F$ `" v5 ], N- T0 [+ _
end5 N# V$ G# g9 f! z
8 Z* r, }# \# E4 n1 Y# d @# E;; Initialize the global variables to appropriate values0 T8 s& q) [+ K% a* L
to setup-globals
) T% ]9 n& W6 o3 J/ I0 p set current-light nobody ;; just for now, since there are no lights yet* @/ T. S9 ` u6 T' ?) |6 L
set phase 0* ^' ?; N( G {1 Y& e: N. D) c
set num-cars-stopped 0
8 ^$ x( G& t5 e* \ set grid-x-inc world-width / grid-size-x& U' y' P* n7 q; i" ^- N0 Z# ]
set grid-y-inc world-height / grid-size-y& c# {3 v7 K* ^( U6 J* R
3 X8 s; W+ x+ Z0 Q" ?: M, G ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
, m, i7 |7 y' _, }, N' S set acceleration 0.099+ T$ e' K6 I) S/ Z& D
end" y0 b) I8 d7 }
6 u$ P1 t, s4 {8 J) G2 h;; Make the patches have appropriate colors, set up the roads and intersections agentsets,& l% m. G( Z1 I% E' K# D6 g
;; and initialize the traffic lights to one setting) _; m6 B" ^' _* u5 H
to setup-patches* x: [( b! G9 u* d1 u& }+ d
;; initialize the patch-owned variables and color the patches to a base-color- X$ a* Z2 c `! O* E
ask patches
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+ P8 h9 i0 } g+ v7 k3 ~4 ` set intersection? false
. t( z, k I; m7 N set auto? false9 U. z/ s" h) J' G
set green-light-up? true7 G) u3 q* v; f4 v9 Y
set my-row -1
$ j% |5 Z; [2 j+ c- @' E. a* U set my-column -1/ O% a" a4 V) I" A8 u7 }3 D
set my-phase -1/ }; ]4 y6 Q8 y
set pcolor brown + 3% k3 e& V: D$ X$ L
]
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7 D/ |* w6 F7 O' z- R) U5 \ ;; initialize the global variables that hold patch agentsets5 s- |3 Z4 o; ~) l0 \; S; @
set roads patches with
2 {1 k, l4 X7 l* S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* ~4 r5 E6 u. _/ o: Y* G/ y1 [8 A1 x0 A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 w5 G- s" G, ]4 T
set intersections roads with2 f4 v1 A4 q. r* x* I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and0 m8 }9 Q6 c% e* d! c: f
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
/ A9 R3 }3 j3 y" ] setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?5 f0 v( }) }& A7 q8 | \
set roads patches with
O, e) ^- f1 ? W( H! X8 v [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* L& ~* D; d8 r8 y" \: s6 L% L (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' S/ T) F. u8 Z/ e# T
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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