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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。
3 ?1 u! h, X2 Pnetlogo自带的social science--traffic grid这一例子当中,
$ Y% ^4 c: u$ P$ S+ F2 B, q0 |globals3 ?/ b1 `( r) `/ R$ P* H4 r. ^
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grid-x-inc ;; the amount of patches in between two roads in the x direction
- q7 W7 @$ L0 a7 F. A' d grid-y-inc ;; the amount of patches in between two roads in the y direction0 K b0 \5 Z0 v5 C
acceleration ;; the constant that controls how much a car speeds up or slows down by if8 [3 [! c; s2 i6 L' ]
;; it is to accelerate or decelerate
6 {3 n4 p9 ?% e2 [; Y phase ;; keeps track of the phase
/ [: d7 P6 w/ x num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure( s. x5 ~; V% B3 ]
current-light ;; the currently selected light' v! P0 u4 I8 v: v4 \
6 D; U# u ~0 }. m' M! g1 y9 ^3 I ;; patch agentsets& n% R/ ]2 p8 V
intersections ;; agentset containing the patches that are intersections
# }* v$ p4 w! U( i' }2 ^ roads ;; agentset containing the patches that are roads D o3 e8 n0 l }# W+ R
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; F+ P" n; S! J. E8 ?5 ^# B2 H7 _turtles-own# i n' E4 A9 B: }' H ?! L
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speed ;; the speed of the turtle4 Q, q: W" Q( U6 a( N) N
up-car? ;; true if the turtle moves downwards and false if it moves to the right
/ F3 |6 f8 A# }' O5 t wait-time ;; the amount of time since the last time a turtle has moved# C" I: _/ K% s0 b! v8 A2 I3 g
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patches-own+ e( `4 w( w, A b+ L9 Y
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; J3 k$ N2 M! Q' z4 E( D6 O intersection? ;; true if the patch is at the intersection of two roads
4 M/ a) ~$ w( \( D+ g1 G: I3 C green-light-up? ;; true if the green light is above the intersection. otherwise, false.7 H) {7 y- T8 \( b' n5 ?* j
;; false for a non-intersection patches.
$ M' V T" y5 ^! Z, i my-row ;; the row of the intersection counting from the upper left corner of the
5 _8 @4 W$ c5 V4 \$ g8 |2 ]6 D# u ;; world. -1 for non-intersection patches.9 Q+ b) @+ i4 T- o5 r, J
my-column ;; the column of the intersection counting from the upper left corner of the* R f4 o. I- s' }# F
;; world. -1 for non-intersection patches.( W/ o* Q. _1 M9 @- z' f1 j
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; k$ }' S' O2 _9 l& F2 z3 a* _ auto? ;; whether or not this intersection will switch automatically.
! G, I3 H% n9 B; \ ;; false for non-intersection patches.; H+ I2 Q. S: d$ S4 M! F
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;;;;;;;;;;;;;;;;;;;;;;
^$ x' q! z! q* m/ H4 p) y;; Setup Procedures ;;
8 r4 [8 ?$ M5 U4 Y;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.9 ~. s$ p6 o7 o5 _8 I! A: ? D# }
;; Create num-cars of turtles if there are enough road patches for one turtle to6 A" c3 c/ v: L$ B2 ~! l: l& m
;; be created per road patch. Set up the plots.1 k) A! h5 z x" H* M& y8 t
to setup7 c4 g2 y4 X; w8 Q
ca
C6 ~ K- r! m/ s setup-globals
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;; First we ask the patches to draw themselves and set up a few variables M" v+ r% U7 v k
setup-patches
3 s r: T! x' \( F make-current one-of intersections
& Y! W3 q) r6 I$ p: K label-current
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set-default-shape turtles "car"
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+ T3 x5 `6 D' m2 ~; B if (num-cars > count roads)+ E7 |* Z0 N$ z4 b) x, w
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user-message (word "There are too many cars for the amount of "
+ o! E' p( |$ B" \- {; b3 n7 L+ S0 b "road. Either increase the amount of roads "
0 j7 m/ `) q+ e# e "by increasing the GRID-SIZE-X or "& a( B! F7 ] W$ X
"GRID-SIZE-Y sliders, or decrease the "/ k& w! r8 q1 V. n, c& g* o
"number of cars by lowering the NUMBER slider.\n"
- ^! O5 A- _( [7 m "The setup has stopped.")* n% I( Z0 H! j& I! r; t
stop
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% ^* N) s0 s5 T B' c: | ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
$ H) r7 P+ O3 ]' ~* \3 I( h crt num-cars
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: L3 {, Q5 ^6 d- ^9 M" G setup-cars0 b8 J' N; J5 e
set-car-color: o8 X: q1 F' R y: f
record-data% m/ G) w' U# n% b: j7 c0 x# B
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;; give the turtles an initial speed
, F4 Q4 r% R7 J- i% W, t! t ask turtles [ set-car-speed ]7 r v, n2 T: r# C& u
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reset-ticks2 C: I1 r2 T( R, ?& o
end
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;; Initialize the global variables to appropriate values5 m* k6 W7 o/ T2 ?1 u
to setup-globals* n' n2 h) j* ?# N+ M( `
set current-light nobody ;; just for now, since there are no lights yet
# s6 _/ K% ~4 N. h set phase 0# ?6 F" q3 u, P7 C
set num-cars-stopped 0
& |# B, s% O$ }% { set grid-x-inc world-width / grid-size-x& {5 g. q2 q2 e, X3 L/ z# Q& N- D8 [
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+ A1 }3 v" ?0 B3 m- a9 r; T
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,% g: V& @4 O3 ~1 U
;; and initialize the traffic lights to one setting
" E2 p8 [! p E1 \5 Z8 bto setup-patches
( u5 D" D0 d0 D# W6 f ;; initialize the patch-owned variables and color the patches to a base-color3 D0 @8 m4 J6 C! {. s2 e
ask patches
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set intersection? false
, ]4 }( Q1 b& B set auto? false$ ^( n5 K& X, d
set green-light-up? true
+ f) H9 X7 T# d6 z4 d set my-row -1
# K( ?8 W9 _- J& c2 w set my-column -1
4 y8 q, M, e# G/ B9 J* } set my-phase -1
5 [ k& d+ R6 O% e set pcolor brown + 3$ ?9 c, K& F+ R$ H% j' M
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6 X+ S' Y" W1 c) y* _ ;; initialize the global variables that hold patch agentsets
! X+ i+ T) _2 H8 Z* R0 G! G set roads patches with
& T( f! K# v7 \$ k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- t' Y5 ^" E8 a* j F
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 a) E6 E3 f" J" Q* U7 f2 `" a
set intersections roads with
' d- I7 q) M: V+ { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
6 d1 _4 U3 l0 u6 t3 @ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 Q7 N" ]7 b) C! q$ T
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ask roads [ set pcolor white ]) l9 L4 M/ c z6 H; J j0 M( j z
setup-intersections
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8 ~- C" h5 C+ I# {: p9 a4 z其中定义道路的句子,如下所示,是什么意思啊? n' c! a) [& Q% i5 Q0 w& O
set roads patches with
Y; M8 h% G4 B" f$ o9 c. r- q" M [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# p& W" e' j7 _0 f2 Z! o& a* ]- v7 O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 {1 S6 H1 I- h K& o* 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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