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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。6 F7 H( ]$ [! w# P$ _( `' B
netlogo自带的social science--traffic grid这一例子当中,
/ A X; z# g! o$ d+ _7 y# lglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction- l0 s+ @) c' u, j3 e3 e' t
grid-y-inc ;; the amount of patches in between two roads in the y direction5 y* c" \" t& Y) E
acceleration ;; the constant that controls how much a car speeds up or slows down by if: w n* W5 D7 n! a& S; w1 C
;; it is to accelerate or decelerate
& h' B- i- Y7 h0 c9 l phase ;; keeps track of the phase/ c* M. i2 H! C6 g. ~2 ^7 E
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
I5 u8 w( J6 s+ Q3 r7 U' [ current-light ;; the currently selected light+ w4 ~( S% i. Z! f' d: d+ x. m
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;; patch agentsets
/ V G1 t0 U T; |& ?: p m intersections ;; agentset containing the patches that are intersections
5 b y" J5 W1 V roads ;; agentset containing the patches that are roads7 u( d( ^8 Z, y( Z7 s
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. m1 X' f7 c3 ]turtles-own4 z q2 p( o- i. X
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speed ;; the speed of the turtle
# `3 u9 v3 l3 D0 U) O4 ]9 D( i up-car? ;; true if the turtle moves downwards and false if it moves to the right
5 V+ @! w+ w2 q8 u0 I wait-time ;; the amount of time since the last time a turtle has moved
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# K7 ]2 E( l9 |1 p5 gpatches-own( y/ W' p/ m8 F) h8 ]
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+ y* N8 P5 W% h. e0 z intersection? ;; true if the patch is at the intersection of two roads
( P6 z! N* r1 U6 b0 I. ?2 N D' D green-light-up? ;; true if the green light is above the intersection. otherwise, false.7 b* Y2 f. s8 `8 n; Q8 c2 J+ [+ r
;; false for a non-intersection patches.
" _4 Z" {6 I8 |# y my-row ;; the row of the intersection counting from the upper left corner of the: ~6 E6 \* g; d, _* X
;; world. -1 for non-intersection patches./ h. {7 e! a) e$ i. i
my-column ;; the column of the intersection counting from the upper left corner of the" M$ h2 x: q4 n9 S: t- r8 x k* {; n. C
;; world. -1 for non-intersection patches.5 v6 Q( j8 P7 @+ a. p
my-phase ;; the phase for the intersection. -1 for non-intersection patches.% G- \; U! A2 s5 h/ r% a
auto? ;; whether or not this intersection will switch automatically.
0 X+ ]. C8 ^; b& ~* H) T ;; false for non-intersection patches.
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5 Q- i4 @6 k! c$ G4 {% i, l. n;;;;;;;;;;;;;;;;;;;;;;4 \! m! F" ~6 b& t
;; Setup Procedures ;;% v" b! u/ R, ?
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;; Initialize the display by giving the global and patch variables initial values.; Q, b8 _/ n9 J0 b! l9 h% b; @
;; Create num-cars of turtles if there are enough road patches for one turtle to+ [9 f/ l& S7 ?" {! K& P' |
;; be created per road patch. Set up the plots.* |( [( W4 G+ w2 {4 _
to setup. e$ y4 X) v5 c
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setup-globals& _, e/ P" } [( q! x+ P8 E8 ^
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;; First we ask the patches to draw themselves and set up a few variables& h: f( z6 ` L$ t& T) a; z$ k( C
setup-patches$ m) I3 S7 k( K& O
make-current one-of intersections4 X, C. M* p: j/ ~) R2 ~* H
label-current! R; p) r7 D5 J: R0 o0 H6 K' p
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set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
0 X1 D, j% d7 M4 C1 X7 A "road. Either increase the amount of roads "
* J4 y3 K, K1 x+ Z0 W0 W "by increasing the GRID-SIZE-X or "4 T) p: S& K& G& c. |
"GRID-SIZE-Y sliders, or decrease the "9 E! B* O: ^! ~
"number of cars by lowering the NUMBER slider.\n"% q0 y: P: q! X, k8 v$ L8 { A3 e; \
"The setup has stopped.")
* H: w. }4 `; b stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color5 G. ^- x8 N) u; u" c& Y+ B. T
crt num-cars- j N* K4 P [. v( M! h
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setup-cars' n2 |) Q( T4 r* }
set-car-color( s2 u0 }2 v- l3 U6 H
record-data. A0 N: D- B# ?9 s- \) \" Q' D8 _! R9 }
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+ F: X) f# _' ^! T' M. ?5 K9 V ;; give the turtles an initial speed' `0 F7 S; h) w( B6 j
ask turtles [ set-car-speed ]
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+ t" ~8 M2 A( t/ w! ` reset-ticks+ t8 l8 r3 p. ?7 e
end+ G' b$ E' i8 Y2 R" f! e8 Q
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;; Initialize the global variables to appropriate values
1 s! `6 W$ d3 ~7 r; u. S. I0 Vto setup-globals4 l; O# ^0 |4 [) v% G7 M
set current-light nobody ;; just for now, since there are no lights yet
6 n2 M' C2 K1 v- @! i$ v4 s9 n set phase 09 n+ ^; U, P1 R, C; E$ b- K; p
set num-cars-stopped 0
+ _3 Q5 G" i" M4 n; d `4 L T set grid-x-inc world-width / grid-size-x
# v$ `& G& h: V# H3 t 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 R3 G' v* e9 M
set acceleration 0.0995 l/ f' y/ `1 S; Y0 D' C+ ~
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
: L4 D9 A0 Y2 }* V1 F;; and initialize the traffic lights to one setting+ R4 C1 Z! j" K8 h9 [7 a
to setup-patches- t# U" A, A, k- I* }7 N& G
;; initialize the patch-owned variables and color the patches to a base-color
: `$ o- k* @# |! D1 y- o ask patches8 l# P+ @) w, u) C; f0 F0 w
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' b5 b( J+ l' t" ~6 H' Z set intersection? false) ?. N8 y3 @# m2 q; c
set auto? false
, L8 G9 v# p) g4 B/ d set green-light-up? true
6 z& W% D6 M" q# X7 I3 `- G, e: M2 d7 ` set my-row -1( X0 h0 T9 N$ w, H0 ~
set my-column -1' l2 ^! h& z& q, p- M" v) k! Z5 l. k
set my-phase -1+ E! O1 {' `, Y5 n1 D! L2 p
set pcolor brown + 3
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) i: ^" u3 ~# E5 [# [ ;; initialize the global variables that hold patch agentsets
! {: Z; f! p3 J. N' w( G2 h set roads patches with
7 F: P( D- _( D! v% V, V1 N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( i/ B7 f( q7 r* n" s (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* w+ Y5 E$ l$ v, p0 @ set intersections roads with# ~, ?: M4 { e% u
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
4 ]4 K# S) S8 e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
5 P$ K" w, Q8 `3 O% N setup-intersections2 W5 l" D4 q. Q: A& B& ~5 e
end
. k+ O H2 C! a7 [+ q4 F其中定义道路的句子,如下所示,是什么意思啊?
& t( E. b5 j w3 Y set roads patches with
! O. X, q- _0 C5 b1 z2 Y [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% Q" ` a4 ^$ l2 s/ j9 {
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 A; }4 s0 ^% r! i1 b& j
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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