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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。
* t" O; \8 n! k& p- V pnetlogo自带的social science--traffic grid这一例子当中,
! B, y* C2 K9 `8 e7 wglobals: @6 ~( r3 l- I0 \4 N! w
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3 g% a6 [1 Q$ w6 z9 J1 o grid-x-inc ;; the amount of patches in between two roads in the x direction4 x) U$ L) [. B5 [0 ?
grid-y-inc ;; the amount of patches in between two roads in the y direction
' k1 K; a9 ?# t" c( p1 k) b acceleration ;; the constant that controls how much a car speeds up or slows down by if$ U' G& D! n" r
;; it is to accelerate or decelerate
' n( _* x) l: j9 H8 D" f' _/ F: A! E# r+ I phase ;; keeps track of the phase x2 w; y. P5 f1 v
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure5 Q" w7 C, \+ {8 _2 l9 d
current-light ;; the currently selected light
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;; patch agentsets
9 T$ x6 z# I* Y: ^- N7 c" t9 s intersections ;; agentset containing the patches that are intersections+ l* ]* Q$ N1 J) \1 F( j" i( y
roads ;; agentset containing the patches that are roads
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6 P7 ^7 X$ r1 _turtles-own+ G* r |! V3 @7 J9 m
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speed ;; the speed of the turtle2 j0 X! P# P# A$ E
up-car? ;; true if the turtle moves downwards and false if it moves to the right3 Y# k+ m- Y$ t( o
wait-time ;; the amount of time since the last time a turtle has moved3 c+ v# b: N9 K& h6 f
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! k0 j* j% h( z* w0 A& Mpatches-own" L0 l. \$ ?0 j) O1 Q
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' l8 V- }' l; L. ` intersection? ;; true if the patch is at the intersection of two roads
: l1 @& x! v: A6 e+ p green-light-up? ;; true if the green light is above the intersection. otherwise, false.# }' ~. j1 f8 Y* G
;; false for a non-intersection patches. ]8 z, {' y" I
my-row ;; the row of the intersection counting from the upper left corner of the
. A. G% {& X4 a( n' A9 ] ;; world. -1 for non-intersection patches.
- D/ A) ^ g { my-column ;; the column of the intersection counting from the upper left corner of the% i2 J* Z8 }0 x2 o; T- x+ V, Y
;; world. -1 for non-intersection patches.
6 m8 E: S4 t: _" a% M# Y my-phase ;; the phase for the intersection. -1 for non-intersection patches.( Q3 c* ^; k# y" |. I
auto? ;; whether or not this intersection will switch automatically.
5 V2 w. t& b. B; o ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;3 O8 M' L: h- v
;; Setup Procedures ;;7 a$ S5 `8 E4 O0 Q
;;;;;;;;;;;;;;;;;;;;;;& q0 H1 V9 d! d/ v& u! U- ?( ^
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;; Initialize the display by giving the global and patch variables initial values.3 p2 Z) P$ k( f% }7 @8 f& S- Q
;; Create num-cars of turtles if there are enough road patches for one turtle to
5 [( Z; p. O+ i4 M;; be created per road patch. Set up the plots.9 Z6 J* d: {' q8 i/ T* m% a& u% r/ o
to setup. F6 V2 G6 R: i X8 _
ca5 l u3 E, t' l/ Y- l" G: @/ K
setup-globals
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- ?3 w% }: C5 \ ;; First we ask the patches to draw themselves and set up a few variables
, s4 L- X2 l0 e setup-patches' I# s9 o$ p/ K$ [9 w
make-current one-of intersections
Y3 E( l4 R% [ label-current% N3 A; G) F5 J5 s; a X4 m7 N
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set-default-shape turtles "car"" x4 N3 M3 }! Q1 h3 n/ x
& O+ u( H" h9 ~+ ]/ q if (num-cars > count roads)' m/ i" f5 ~6 @% s: Q
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5 M# V( y# h2 n7 |1 G6 X user-message (word "There are too many cars for the amount of "- R; E0 m. P* x1 P
"road. Either increase the amount of roads "
: m3 T% Y. G9 M- j8 c "by increasing the GRID-SIZE-X or "
# r2 b3 [( C! I3 h/ W# f "GRID-SIZE-Y sliders, or decrease the ", ^/ y3 t6 c$ V, p4 X
"number of cars by lowering the NUMBER slider.\n"
8 k' {5 C7 z* T c "The setup has stopped.")4 a' B1 ?. l% ~2 O- R
stop* X; u4 G0 Q" _' v; I
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7 e- _2 w& `7 j1 n0 `: ~7 p: e7 W" S ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
) N1 m/ F' K& S' w0 Q7 r crt num-cars
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setup-cars; B* L2 ?8 i6 r) L* P
set-car-color' w4 f' g9 o% W4 P. ^" z
record-data
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;; give the turtles an initial speed
7 a, t5 L6 B1 S( a$ R7 Q$ M9 q ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values1 s6 o; {/ l1 d. P
to setup-globals9 Z* l) T) c3 I# R# P9 x
set current-light nobody ;; just for now, since there are no lights yet
8 S. ~ H, f8 ]( k. L, c set phase 0
8 ]1 I: [8 Z4 K H# i' R/ g) v set num-cars-stopped 0+ Q" r( ?' p V/ w; ]. a
set grid-x-inc world-width / grid-size-x
3 ?# `, B+ H, D set grid-y-inc world-height / grid-size-y
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+ o+ `6 ^3 K: P) O6 }( r3 M ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary3 [: Q. \1 p( W' p6 A2 [& V( r
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,' g: b* Y' a L$ s0 R0 A2 t6 o
;; and initialize the traffic lights to one setting
2 h2 Y q3 Z7 r6 t8 m& Nto setup-patches" g- ]6 \' n6 X2 H7 o
;; initialize the patch-owned variables and color the patches to a base-color
6 z. M. @% n0 A- E ask patches/ L4 c: @7 ^- D) I5 l
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9 g6 [! r' h5 I; v7 Y set intersection? false) G/ H4 c) E/ e& Y
set auto? false
* V/ _8 S3 {" M- A- } set green-light-up? true! l/ p# R1 i7 w: e7 {, f% C
set my-row -1 K( q; z/ j6 F$ t3 @4 c! ?9 D' n
set my-column -1
8 i3 g9 x3 c& [" O; X1 h( Z set my-phase -1
2 t- J, y6 M6 A/ {5 @2 ?! H' ] set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
, ?$ @" z! t' [) e set roads patches with8 D" p/ b5 R6 j% k/ `- o
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& i2 @/ a; f% L6 l
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 x7 M. l7 |7 [4 P1 u set intersections roads with
; `, Q3 m5 D4 v' m' ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and5 X! G7 Q% Z! P- T* F; @/ u+ A/ O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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. j; p6 j$ T( @* X% g& U5 a ask roads [ set pcolor white ]
. l! x- L1 A/ ^6 P setup-intersections
- i o8 z* G+ G: t" Z; |end
! h1 ^$ o) d% Q# u其中定义道路的句子,如下所示,是什么意思啊?
: k( n& B$ B2 Z' @, b- F/ X set roads patches with/ k, E$ x. E b# Z8 d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: C r1 o2 k7 U' a2 x" `/ o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 G6 s- h Q$ \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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