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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。, K2 }5 H7 `" o7 C6 @( y' b# X/ S
netlogo自带的social science--traffic grid这一例子当中,; M3 W7 A0 w1 u& }
globals8 y# M" O% u3 C5 U( [
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/ m) ? S4 U. P( h X( ^5 q2 I grid-x-inc ;; the amount of patches in between two roads in the x direction
! y+ W3 m- Q+ B grid-y-inc ;; the amount of patches in between two roads in the y direction
4 i; U' N) ?: Q) ^$ o5 ~ acceleration ;; the constant that controls how much a car speeds up or slows down by if% t8 A, x/ s3 U
;; it is to accelerate or decelerate# f5 v+ f/ u0 m' p, r+ f
phase ;; keeps track of the phase/ O3 |' S0 Z, V1 {5 X" ^
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
9 J# ~$ w( H) ?4 M current-light ;; the currently selected light! I& M& s4 a7 s/ k+ @
9 ]. Q9 |& b' a# h3 @) x* U ;; patch agentsets
" g' n7 {5 g8 b( H6 R# g1 G intersections ;; agentset containing the patches that are intersections
% O& U( n" O' c/ P# R5 q roads ;; agentset containing the patches that are roads
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turtles-own5 A+ b: ?& k/ c+ Q' V
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speed ;; the speed of the turtle/ E A% \( R( m* A- M5 ^" W+ z0 Z0 f
up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 |/ S6 }* ?$ p) T1 o! S wait-time ;; the amount of time since the last time a turtle has moved2 k# [) K$ F0 ?9 `4 K: ^: G8 {
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
s% j# v4 I! c9 u' m green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 @6 v; T; q# n; _* W- D
;; false for a non-intersection patches.
, |1 d" \$ o3 T my-row ;; the row of the intersection counting from the upper left corner of the
# a/ d; d8 O; @ ;; world. -1 for non-intersection patches., }* F, J P; H) R; e# @- i
my-column ;; the column of the intersection counting from the upper left corner of the
& v" O$ ~" S* \& Y7 q ;; world. -1 for non-intersection patches.
# ^4 ?& S m& z8 O/ m& I$ H- \) j& O my-phase ;; the phase for the intersection. -1 for non-intersection patches. K6 v% X5 D6 e! ~ V. g# E0 l
auto? ;; whether or not this intersection will switch automatically.& ]! n) d0 l* l
;; false for non-intersection patches.
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" a5 P& J& [- \1 K0 Q8 X" K# {;;;;;;;;;;;;;;;;;;;;;;, h! [! ]. J3 u3 N( u
;; Setup Procedures ;;
, f% r4 l$ n6 J;;;;;;;;;;;;;;;;;;;;;;. T/ r. l4 l2 S+ U, i2 D$ s0 m6 I9 I
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;; Initialize the display by giving the global and patch variables initial values./ u* V) v$ m4 ]4 y0 q6 i1 A5 M0 `
;; Create num-cars of turtles if there are enough road patches for one turtle to' Z' Y6 n, s& P- q, j+ d' D
;; be created per road patch. Set up the plots.+ o- N$ ~) u0 Q! {8 F
to setup* q7 [, G' s# R' d7 E
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setup-globals9 L' b& e; _/ m, \* a" r2 f
_% _/ b4 r8 w/ o7 D. C0 Y# U ;; First we ask the patches to draw themselves and set up a few variables* I) W& \% P% q- l0 W0 f6 g
setup-patches8 X( X3 p( G6 Q0 \! L
make-current one-of intersections
" \ Q. n* `$ f' w2 O label-current
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$ L& F" e# n. ?5 x# h* e set-default-shape turtles "car"
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if (num-cars > count roads)
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0 g( p% y9 y2 J& c! j3 J: e user-message (word "There are too many cars for the amount of "' [0 d! X& r) h* m7 y
"road. Either increase the amount of roads "
) a2 y( `. E4 V$ m3 T "by increasing the GRID-SIZE-X or "
3 g$ p3 `% ?: h3 f# Q# L0 Z "GRID-SIZE-Y sliders, or decrease the ") s& |5 |: L- i
"number of cars by lowering the NUMBER slider.\n"
) V1 J4 Q# I7 ]% h: B& \2 _ "The setup has stopped."). T; b( E4 u' o0 O
stop8 Q. z' [: _* X7 S# p5 e/ S" W
]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 N5 O3 n5 k( k | crt num-cars
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setup-cars
) J8 @. c( _8 V) ~2 n) Q | set-car-color% F- y3 K7 F0 G0 Y- n) a' {
record-data
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;; give the turtles an initial speed6 H& D5 d3 [) U& d
ask turtles [ set-car-speed ], |! m8 e- J) V% X z6 J& ~
2 m! @% H; ?! m' L5 c reset-ticks& \( m- R) n- f+ G* W6 a7 B
end
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; d0 Q5 K! ^9 K8 @;; Initialize the global variables to appropriate values( q/ }& }# N1 y. O8 h A1 _* Y1 L
to setup-globals+ }# g# y3 n) s+ ]
set current-light nobody ;; just for now, since there are no lights yet: E- A2 Q& [/ @6 S0 J! V
set phase 0
8 z$ z7 h) p. ~# L$ {( r set num-cars-stopped 0
3 Z- ?1 j2 @4 J" o9 W$ c: g set grid-x-inc world-width / grid-size-x7 a G" Y% U0 ~* C" C$ l, }
set grid-y-inc world-height / grid-size-y# y( x9 y, I* j! ~' J8 I
* k5 G8 \3 }6 A" E2 _% S& l ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
d) ^- ^; g& H set acceleration 0.099
0 h8 I5 }6 [5 [# ], w5 n! [end7 g3 B7 ?2 Y% |& j% y( z
8 ~, W6 Q. s; U) h;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
2 J0 E0 U, G9 S* I! X;; and initialize the traffic lights to one setting; r6 ~2 d, @/ D9 S" b. K" v
to setup-patches5 L8 z# w5 k2 ?- h6 H: X
;; initialize the patch-owned variables and color the patches to a base-color
6 _2 O e) \ v- ?7 A6 b0 i2 l ask patches
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set intersection? false
, V$ ?2 A, _$ O* G. ?! p4 { set auto? false- k- G, Y u9 M6 m
set green-light-up? true
$ |5 B! ]7 c- P8 E5 X set my-row -1
3 v' T, U2 U$ o: u set my-column -1
" m, N. U, ]# @4 @0 m set my-phase -1
' d) ?' C6 m" a3 p) n8 J/ I1 k set pcolor brown + 3( q* `) Y4 X- U2 v8 Z; z! s: _$ o0 r
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; F0 r- h, S5 g7 _ ;; initialize the global variables that hold patch agentsets
5 ~+ L$ C/ }" u, _. {) o& c& K set roads patches with
4 F4 f$ g2 O& p) ~& _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or* g5 \0 { h, }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& U6 o4 g) z" B# r
set intersections roads with' S3 d+ O. m4 a& M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and1 t" [" x2 O9 k
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]; Z% E9 {* ` C. l
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?
- n0 Z4 m( ^# T5 t set roads patches with9 {7 X: \, h( ^" V5 t% o
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; B/ h. i# h' j' y6 m1 N- `) v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) ~, s0 O! s: V" B; I* ?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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