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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。- k6 p4 C) j$ q
netlogo自带的social science--traffic grid这一例子当中,+ `0 y% {: j( d# b% _
globals' o, K7 ]1 n( P0 V4 c# `: K0 o2 u+ A
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grid-x-inc ;; the amount of patches in between two roads in the x direction/ Q4 Q7 [$ t2 y$ K6 v8 E2 n$ M- K
grid-y-inc ;; the amount of patches in between two roads in the y direction
( S- w) }2 w- ^( w( ]* b acceleration ;; the constant that controls how much a car speeds up or slows down by if+ \( f. k: B0 a( z, w! L
;; it is to accelerate or decelerate+ k( z5 J) [$ u5 m' J
phase ;; keeps track of the phase) w6 t& }8 f4 c, z+ J: M1 z
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure$ D6 S0 o1 G. }9 e# a7 z! w
current-light ;; the currently selected light& }, d7 }) C+ Z' o
) n, I6 S9 E6 `" B( K2 @$ p/ q0 X5 S ;; patch agentsets
% M" z4 c* c0 T# J0 P1 \# F intersections ;; agentset containing the patches that are intersections) b. M8 u7 \0 p) H
roads ;; agentset containing the patches that are roads5 w( w* z& i& Z# {! G" [
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; E! d! |" q( c0 ?' Tturtles-own& n5 i+ _2 h& W/ H/ v0 O& X
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- U9 m% M4 H6 G6 z* `: U speed ;; the speed of the turtle. o, x4 O4 h F9 Z
up-car? ;; true if the turtle moves downwards and false if it moves to the right
) i7 Z8 Q$ I- H3 u" E# G9 T c wait-time ;; the amount of time since the last time a turtle has moved5 ^# V! c$ s2 h9 F9 E! ?0 f2 M
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1 @- n1 b9 A% q$ f1 G' L+ @patches-own
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intersection? ;; true if the patch is at the intersection of two roads" k, u5 x+ K/ b5 v7 `
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
( x5 b A' V% G. B ;; false for a non-intersection patches.+ i4 C* I9 `- Y) S+ j* l' e
my-row ;; the row of the intersection counting from the upper left corner of the
3 |# X' e0 e Y0 _6 [ ;; world. -1 for non-intersection patches.: ^5 y W5 y5 W8 `
my-column ;; the column of the intersection counting from the upper left corner of the
4 f% \1 P$ {% z& n5 ~" p5 [ ;; world. -1 for non-intersection patches. V# ^; m9 C2 O) m
my-phase ;; the phase for the intersection. -1 for non-intersection patches.. y) M: J, R0 Y0 v3 o5 n
auto? ;; whether or not this intersection will switch automatically.
( r. [! r1 f) U( _( @0 [( @3 v ;; false for non-intersection patches.
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7 j) D* F' i# k0 w2 _;;;;;;;;;;;;;;;;;;;;;;
" k! s" ?9 d c% r; e;; Setup Procedures ;;8 Y; H2 F" P/ O l" I3 J
;;;;;;;;;;;;;;;;;;;;;;7 a: R9 i7 C, G% g" K& u& s* A3 v
, Y$ _. J8 ~# N;; Initialize the display by giving the global and patch variables initial values.+ n1 |, w. h4 ?+ ^) d. b3 e8 |
;; Create num-cars of turtles if there are enough road patches for one turtle to8 A0 K- R, }5 I7 u
;; be created per road patch. Set up the plots.7 I j* ^( \8 o- }, L/ j) d
to setup2 K4 F' ^- ]0 V- _0 y
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setup-globals3 G' {( G0 g; y- a+ h9 K
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;; First we ask the patches to draw themselves and set up a few variables
3 ~+ K% v6 D. F0 ^" t$ x* ^6 L setup-patches0 @8 k1 M% J u/ O, Z
make-current one-of intersections
! A" [/ g R* y6 b2 ^ label-current
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set-default-shape turtles "car"" y) Y# p9 Z. G6 N' W9 v
0 q- r E3 d0 x. }+ c8 o if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
& j8 A! t, n5 ?( @6 B' u5 D% y) Q "road. Either increase the amount of roads "! W' w1 F* L2 }7 X7 I5 V
"by increasing the GRID-SIZE-X or "! P! N6 ^* D. M/ [! t, M' s; j1 Y2 M9 _8 j
"GRID-SIZE-Y sliders, or decrease the "6 K, {# N' z2 v. X x& K; S5 ^
"number of cars by lowering the NUMBER slider.\n"8 H- b" J/ u: T' X
"The setup has stopped.")
0 s9 D/ \. T9 @3 x* Q stop+ L( H+ u$ ?% r. ]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
/ X T. d9 j9 B0 x crt num-cars. u& q! n0 R( u4 r! `, D
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setup-cars& d6 ~( S2 ~- r- h7 Z, D- `/ ~
set-car-color
3 E8 b/ ?, [7 m8 ^5 X record-data! f. }1 ]* m' ~& Z) W
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;; give the turtles an initial speed( w" A" H# q. s8 B
ask turtles [ set-car-speed ]
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" P, p- v, ~" _- i1 z; k( q- C reset-ticks
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;; Initialize the global variables to appropriate values6 D) B; G; i1 n% B3 w' c: H4 g* |3 j
to setup-globals
$ x; Y: o4 Z1 o set current-light nobody ;; just for now, since there are no lights yet4 P' Z$ D. m! r" ^
set phase 03 W. O2 Y9 M7 _9 o2 T& H5 Q4 v
set num-cars-stopped 0
- t5 d* ^1 |& A' [7 e set grid-x-inc world-width / grid-size-x
8 G3 X( x/ E" j. i: M6 Q- y3 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 boundary5 w) ]! ^7 w( K
set acceleration 0.099
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- I1 P: K8 } _;; Make the patches have appropriate colors, set up the roads and intersections agentsets,! {9 R t* ~' m Q
;; and initialize the traffic lights to one setting2 E; `& l- v' V0 b! B7 }
to setup-patches
4 _6 d* l8 o8 K" C% v% [8 ^ ;; initialize the patch-owned variables and color the patches to a base-color
3 x" @ T$ R8 o( X ask patches' K3 M1 A) z u/ ]
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( J. V, b- M5 D. I! s2 _ set intersection? false5 ^+ q$ r( Z2 {# H4 ?" z, @
set auto? false m" d3 ~: X- y# l. j6 U
set green-light-up? true6 K, O8 m8 e( J
set my-row -11 H3 j7 _. S& Y0 X! s
set my-column -1( \0 w8 ?6 r- n( x2 [, B
set my-phase -1
7 j+ c7 ~# [# l3 L! _& H! R set pcolor brown + 3% ~8 U0 Z: c/ G3 I# c0 e
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;; initialize the global variables that hold patch agentsets) t1 s2 ^' p# Z/ a! X5 @
set roads patches with I# q- N: I4 S$ l
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% A8 `2 n" h9 X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ \6 u) m( M2 |% p5 i set intersections roads with
) Y7 ?' c0 {" h2 r0 d9 \ _6 d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and. E8 F2 B! K0 w4 @
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]: h: |$ E9 \7 f* O2 @- f: @, r
# b: U4 O* }5 l# m( P! B ask roads [ set pcolor white ]- H+ d+ R* {7 R' @
setup-intersections1 i: W0 }) O8 m9 Y* w0 m- \0 a# J
end# N R% {: @0 E9 }2 b( J- Q8 a
其中定义道路的句子,如下所示,是什么意思啊?0 t! @# |( O7 m
set roads patches with
& W) D0 M% l0 G& x2 P [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or+ ?6 q$ P8 ~1 _; O2 p' z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]; A- R D' `7 C
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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