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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。2 f# T. W P9 Y: A% U0 @4 \7 g
netlogo自带的social science--traffic grid这一例子当中,+ p& Q8 ` ? k) n8 P+ d8 V$ A7 V* L
globals( P' x2 f# D: W
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grid-x-inc ;; the amount of patches in between two roads in the x direction
, }- v" ~/ i+ C& R- V grid-y-inc ;; the amount of patches in between two roads in the y direction
* S# I, [; W! W4 G acceleration ;; the constant that controls how much a car speeds up or slows down by if, [0 v& c5 ]' P |/ u. ~* q
;; it is to accelerate or decelerate- H7 \1 H; L5 v4 A' [
phase ;; keeps track of the phase
- q% r0 t* I% H2 A# s5 M num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure/ B& ^, [8 i. S
current-light ;; the currently selected light# y; Y3 K" b1 h- d* ]1 u# [4 I
' J" f: V2 \7 [1 b4 I+ N ;; patch agentsets7 ?0 R; t- e& y9 F& S; d
intersections ;; agentset containing the patches that are intersections
1 k, h( E% k+ P W ^1 u/ `0 w2 ] roads ;; agentset containing the patches that are roads' E! l, }) L3 Y$ ~ W0 n. ]! _
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% ?( Z# @, a2 u2 J2 h3 H) Zturtles-own
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# t: _# ]( e @% [ speed ;; the speed of the turtle
' F$ l) U: i( ]& S! b5 Z& f t. U up-car? ;; true if the turtle moves downwards and false if it moves to the right1 Q6 K& ?: a( \. F. H2 {$ J \
wait-time ;; the amount of time since the last time a turtle has moved4 N; C2 ?2 R4 o7 ^! X8 P, l0 W
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
, t: _& a8 m- N0 i, M3 ` green-light-up? ;; true if the green light is above the intersection. otherwise, false.
$ }$ c$ P/ t! _; S$ {. {+ N ;; false for a non-intersection patches.
7 U4 j% t+ v \- r) R my-row ;; the row of the intersection counting from the upper left corner of the
5 @) c! Y' T8 e- O ;; world. -1 for non-intersection patches.5 C% F) p2 }) @$ N+ w M
my-column ;; the column of the intersection counting from the upper left corner of the
2 E5 E$ e, a& O% z ;; world. -1 for non-intersection patches.
7 L0 P9 L& ?' P3 q my-phase ;; the phase for the intersection. -1 for non-intersection patches.4 y, S# u5 I; x$ Q7 ^! H- X
auto? ;; whether or not this intersection will switch automatically.
4 A) W- {* a! p. `7 y ;; false for non-intersection patches.; s) I' [# D& O y5 Y7 ~
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;;;;;;;;;;;;;;;;;;;;;;6 ?; v! P4 c- w9 t& e
;; Setup Procedures ;;# G3 `$ m) J! z6 |1 x" |6 ~
;;;;;;;;;;;;;;;;;;;;;;
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$ @8 O8 C/ z( ^/ z/ C;; Initialize the display by giving the global and patch variables initial values.8 s, m+ g1 z+ \) Y) }( x
;; Create num-cars of turtles if there are enough road patches for one turtle to
4 t$ V' w; h2 d5 [;; be created per road patch. Set up the plots., h! W' [7 m. k/ c
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
$ \' h! ?; K0 B* m3 _; t" ~& ~ setup-patches4 h' `" Y2 H8 Y. [1 m
make-current one-of intersections
8 d _' O! B+ x# E/ R# Y$ O label-current
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' {1 t u: o$ G" K' X' C- W: n set-default-shape turtles "car"
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* Z; L% H+ v5 u% ~ if (num-cars > count roads)) U& W. E- L3 j; T
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user-message (word "There are too many cars for the amount of "
9 j5 d& ^- B- M- L0 }' n% }; l, t; d "road. Either increase the amount of roads "6 S/ t' z( i# \3 Q
"by increasing the GRID-SIZE-X or "6 ^4 C8 T+ k- Q0 z* ]1 ~
"GRID-SIZE-Y sliders, or decrease the "
0 J5 v3 m1 _. L6 [+ v f "number of cars by lowering the NUMBER slider.\n"- R) u; R+ E# s3 U
"The setup has stopped.")$ I$ R& G5 F4 A. f8 n: P
stop L0 w9 Q( E( Y _
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$ t2 p" v& ]0 p- f; B' ? ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color% t$ c. `9 m# `
crt num-cars
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setup-cars
+ }: N: S3 c% H2 Z' h set-car-color
8 | k9 I3 c8 c+ k5 Z record-data: z, t3 O) y* M* |% i' E" E: F+ T# q
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;; give the turtles an initial speed
; R+ t% W3 C- s, G3 L ask turtles [ set-car-speed ]% h) V! r; [" n0 r* z2 F5 ?& s3 f
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reset-ticks& z L9 k# c( E) A
end
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;; Initialize the global variables to appropriate values
) a1 N0 L: Y4 e; Nto setup-globals
; f/ v8 n3 P4 a5 b set current-light nobody ;; just for now, since there are no lights yet7 I/ O& e2 A1 }: n! c$ i2 ]; r
set phase 0
" h5 W. ~1 A; p a u set num-cars-stopped 0/ z3 A, ] D+ q2 s3 \3 G* w
set grid-x-inc world-width / grid-size-x' H- P# W* Z) f2 n4 Y% ?
set grid-y-inc world-height / grid-size-y0 ]% [. u# U! s* I: \
- ~ b# [( D, f4 `7 I" s8 m& a ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# O, J* a U3 \6 M3 B set acceleration 0.0995 K7 n2 K% J/ a9 U$ y0 k2 J
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
6 J6 x) Z( O) a/ ]( b;; and initialize the traffic lights to one setting
( z1 Z4 P7 f1 H, W7 Z* b; V# Jto setup-patches: o1 y; o h ~2 ?
;; initialize the patch-owned variables and color the patches to a base-color4 E7 B; p) ?: A7 T3 ]2 h5 x- W
ask patches
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set intersection? false
( b# Y4 a1 } t) L: P2 c( {/ F set auto? false5 _+ a) J4 N" `- g5 V( P8 w( E
set green-light-up? true
8 F9 o& g6 `/ k1 s" ~ set my-row -1
( `) S. g7 m1 o: y set my-column -1
; v( [, s3 Q" s' p set my-phase -1
& w$ c' v3 U2 O8 J set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
* n# ^9 Z6 U) u set roads patches with
* L4 Q# D& g [+ p [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 V2 b: U/ f I8 J! b. G7 T
(floor((pycor + max-pycor) mod grid-y-inc) = 0)] s' x1 Q* `: X3 i8 S# U( m7 }
set intersections roads with% c& ?0 Z. C7 g9 v" \6 b* e2 l( G
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
7 L) J0 c. m$ H$ H- m (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
. E' a" ?! I2 K3 }9 z setup-intersections& B: t; ~9 m. R* m2 H( }, R; r
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其中定义道路的句子,如下所示,是什么意思啊?
( z$ E+ U: a6 |6 L5 J- Z* X8 a% } set roads patches with" J" z9 W! S& _/ \1 M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 P: J) w) s- }4 |0 f
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 C4 z* g1 c; m; v0 D4 O
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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