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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。
" @/ ~1 i$ \. C' X. v( {netlogo自带的social science--traffic grid这一例子当中,
! c! Q$ q2 g. S$ m" Q- F1 wglobals# n4 ?0 w) ]) V: ^* Q q
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grid-x-inc ;; the amount of patches in between two roads in the x direction% Y8 o% @' E# J) V
grid-y-inc ;; the amount of patches in between two roads in the y direction
# A) \5 u- D6 h3 q# u0 c* Y acceleration ;; the constant that controls how much a car speeds up or slows down by if G9 b0 b3 B: [% L" v
;; it is to accelerate or decelerate
/ l+ Y3 z2 T0 B, S+ M phase ;; keeps track of the phase2 G* a* ?& R, C) X( b6 V1 @+ _$ ^
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure$ w$ k1 K9 h) {2 w5 m! j
current-light ;; the currently selected light3 ~; M1 w" p# }2 V3 l4 ]7 A
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;; patch agentsets
L8 R0 @9 Z& q5 u) F; C- o intersections ;; agentset containing the patches that are intersections* ?# k+ `8 a; O1 D; |3 v0 c4 s2 t
roads ;; agentset containing the patches that are roads3 D& A" f: X& ^( Q; N) e! X1 a
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turtles-own4 c: m- `% k+ c" [0 f, W
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speed ;; the speed of the turtle
" o$ n4 b" j, U' c3 W up-car? ;; true if the turtle moves downwards and false if it moves to the right( J/ i }# J2 l. ^; X
wait-time ;; the amount of time since the last time a turtle has moved$ n7 h0 Y- D* Z6 W @0 b
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8 w4 I9 g6 q5 Bpatches-own
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, s5 z/ e8 E; z& k# G! A7 L intersection? ;; true if the patch is at the intersection of two roads5 ]; t. L7 }& z( a* K/ Y; I
green-light-up? ;; true if the green light is above the intersection. otherwise, false. P: t) e# b( f6 m$ B
;; false for a non-intersection patches.6 | I& ]; v& Q7 I4 x& } h) k
my-row ;; the row of the intersection counting from the upper left corner of the, H9 g z2 Q4 e3 q/ @! t; g
;; world. -1 for non-intersection patches.
T: e# \( l+ V my-column ;; the column of the intersection counting from the upper left corner of the1 u7 e* F) h% X) \
;; world. -1 for non-intersection patches.7 ]0 v1 G" A: H( Z7 Y0 y7 `* k/ r
my-phase ;; the phase for the intersection. -1 for non-intersection patches., h) e& q$ j- L
auto? ;; whether or not this intersection will switch automatically.
$ P5 p) v/ O! n! ~* Y/ p% c4 ?# { ;; false for non-intersection patches.2 A7 R' J" h% A5 F1 T
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- ~7 E$ ^; V, K;;;;;;;;;;;;;;;;;;;;;;5 f5 h2 [" s6 J4 ~
;; Setup Procedures ;;- v3 v8 y, O2 {8 \1 B4 N
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
[5 U% q" n' h+ n;; Create num-cars of turtles if there are enough road patches for one turtle to9 n- }% V P8 H. k
;; be created per road patch. Set up the plots.
; z, |) Q6 C2 @/ @to setup
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setup-globals8 _0 t$ l L2 G. E% \( B& }1 r# L0 f
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;; First we ask the patches to draw themselves and set up a few variables/ T0 h' u- b, K7 p9 m2 W
setup-patches
4 o3 m2 O: t; h2 J1 ]5 z make-current one-of intersections9 b- ?9 }# z# \. m& O
label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)8 r- W+ ? v+ }6 A, }' t$ I& J: S
[
. z- j9 [0 ~. d+ a3 l user-message (word "There are too many cars for the amount of "3 Y1 F! O& J. O/ U( I( ^+ Y
"road. Either increase the amount of roads "* J9 ]- p/ Z" z4 L# E
"by increasing the GRID-SIZE-X or "
# L7 Y4 t6 a1 C% U2 i1 d7 X1 z6 @ "GRID-SIZE-Y sliders, or decrease the "" J* S3 u8 u+ q& {" n9 J2 [
"number of cars by lowering the NUMBER slider.\n"8 t2 a; o. r7 B' J# Z& ?2 }5 r
"The setup has stopped.") u1 }- y" v6 F
stop# Y& }7 j6 W* I8 ^5 c
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. S! s$ E) u1 X9 k1 A" d ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color! K. n* u7 h: ]# c) n; _/ j/ p. J
crt num-cars0 W( ?5 S; s$ @7 m0 z
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( Z* `$ |0 z4 O" J setup-cars
* i7 x9 T: \6 W2 p" F/ Y: n set-car-color
0 @" Z! v7 \/ w record-data
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8 Y, V2 t% s" r' \3 O ;; give the turtles an initial speed
6 A. b0 D( o+ P _6 q5 N ask turtles [ set-car-speed ]# h7 j- w% V4 L
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reset-ticks
( f. P3 Q! \+ ^) t! T6 L9 I5 S3 Oend
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" v. s0 ] a& B2 i: \8 |8 G;; Initialize the global variables to appropriate values/ D5 Z L- }; M. a' t t
to setup-globals
* z- Z- Q: {* ]9 }4 H set current-light nobody ;; just for now, since there are no lights yet
0 t1 Z0 t( m$ D4 E$ | set phase 03 E, {& [" c2 z( r* U |
set num-cars-stopped 0& N8 L1 z1 E- r. P
set grid-x-inc world-width / grid-size-x6 e: Y5 U- Z$ e; J
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
/ f; D; [" B" C$ a P set acceleration 0.099
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6 s# x( @8 b6 n( ^;; Make the patches have appropriate colors, set up the roads and intersections agentsets,/ o7 l# ~# d: {$ C7 n' h6 I
;; and initialize the traffic lights to one setting
; C9 r. q" B7 dto setup-patches
' I: @+ Q# }3 H5 H3 {/ o; ^ ;; initialize the patch-owned variables and color the patches to a base-color
/ T' N( Y: ?% ^+ Q p/ ` ask patches' F' B: e, J# O0 j5 r- R
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set intersection? false
; z' G+ E/ s; y+ a" w set auto? false
3 J G; d+ ~; S, m" l set green-light-up? true
+ ]" I( V1 s# ]/ I set my-row -1
* h7 `6 P& O/ J! V set my-column -1
5 i, h0 E a" K set my-phase -1
3 b0 [- q$ U; F5 C set pcolor brown + 3; q2 m6 l9 F) @) |1 Y; _# c* E
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5 `9 c6 r2 o% }: v' b ;; initialize the global variables that hold patch agentsets4 J$ `" ~5 o3 K# w2 a0 w7 F
set roads patches with) F1 |8 Y& j. V' _/ s2 E8 O
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
! v4 G% l4 [' S( T8 ?2 H+ l$ k- d2 D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; L8 O7 \& j" u! P set intersections roads with6 y0 H/ Q+ K/ b
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and+ }" i! B/ i) ]: K
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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" o M" ^3 q1 r% x# T7 q: s ask roads [ set pcolor white ] _8 s# u" q2 \( w) z1 W9 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?* s3 q, B$ b6 {
set roads patches with
, r% \5 b/ {( U0 ]' u! D [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 f- O7 J) a3 b% m (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( K+ g8 f# \9 b; @+ z
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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