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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。
4 h; F' R$ k: A9 hnetlogo自带的social science--traffic grid这一例子当中,0 P( a: _ x1 ^$ v" r) k7 S4 @
globals
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, |0 Q* ^1 H& o% O grid-x-inc ;; the amount of patches in between two roads in the x direction" w3 k! v3 K6 @9 J5 q g
grid-y-inc ;; the amount of patches in between two roads in the y direction. I0 E, p; N2 g/ b- m
acceleration ;; the constant that controls how much a car speeds up or slows down by if" @. p/ {, _3 Y4 Y
;; it is to accelerate or decelerate$ n, R/ B$ u5 N. k" W
phase ;; keeps track of the phase9 i, e* j+ U/ z, |, K; |
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
7 M! P$ z1 D( @6 S current-light ;; the currently selected light- @, s' R" X0 G& X9 ~
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;; patch agentsets S B3 e5 I' q
intersections ;; agentset containing the patches that are intersections# c; Z8 z) m& ]9 P8 c9 y- d7 p# ~
roads ;; agentset containing the patches that are roads
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turtles-own
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7 D, u1 `0 j0 }9 m7 Z speed ;; the speed of the turtle. t! n& e4 \. s, H
up-car? ;; true if the turtle moves downwards and false if it moves to the right
) h. o) F5 A+ i9 O5 n' J. ] wait-time ;; the amount of time since the last time a turtle has moved% O1 p9 D5 [* t; r/ M5 w' ^
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. N7 B5 D! P, _( `patches-own; h/ }% ^* F' ^ }
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" E% W, T- q$ q4 E) R* ]" S intersection? ;; true if the patch is at the intersection of two roads% {3 \2 B4 h* }" d8 z
green-light-up? ;; true if the green light is above the intersection. otherwise, false.2 J/ {) z! ^- N5 ?" ?
;; false for a non-intersection patches.! p/ ^1 n7 C; R) M9 _
my-row ;; the row of the intersection counting from the upper left corner of the/ \; O* b B2 i
;; world. -1 for non-intersection patches.
6 y- ]1 @( ~2 c n+ J5 O my-column ;; the column of the intersection counting from the upper left corner of the
" l1 L$ j* E2 W! g* |: N ;; world. -1 for non-intersection patches.
; w! D+ L" t, t* e6 \# ` my-phase ;; the phase for the intersection. -1 for non-intersection patches./ q/ ^7 s: h9 P4 n' | @4 m
auto? ;; whether or not this intersection will switch automatically." Y/ l$ w2 W3 [2 E
;; false for non-intersection patches.5 @. a1 b$ [; \8 q6 u4 R. L
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4 I( q/ i7 e% V2 Z0 q* Y;;;;;;;;;;;;;;;;;;;;;;+ J% C9 }3 u* h7 R& _
;; Setup Procedures ;;2 k( v# m% Y, ?0 }; _' [$ k) k, | |
;;;;;;;;;;;;;;;;;;;;;;0 U# H% u5 h3 M: F6 Y+ e* t
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;; Initialize the display by giving the global and patch variables initial values., w2 q* h2 a5 `/ N" B
;; Create num-cars of turtles if there are enough road patches for one turtle to- z1 X" n5 K* }& ?+ a2 i# t) h8 P1 S
;; be created per road patch. Set up the plots.1 D+ B4 g1 h6 x; x
to setup
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% I, [8 s; X7 V' U2 e/ I setup-globals
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w- p$ p" {- M6 M ;; First we ask the patches to draw themselves and set up a few variables) }! s* ~# [" [7 t, G% c9 s
setup-patches
# c8 d5 w" p0 C4 u, r Z, i6 T make-current one-of intersections
& m9 j( k0 f' \, h# Y label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)
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: @& E: G* B$ t- h; j+ B user-message (word "There are too many cars for the amount of "6 c5 B5 }: M2 s( X3 ?
"road. Either increase the amount of roads "
! t3 b8 R" k+ S$ p0 H3 R: [ "by increasing the GRID-SIZE-X or "
% o& ^% G+ u$ b1 p: z/ D "GRID-SIZE-Y sliders, or decrease the "
9 ]1 N" q( r4 l. I6 E "number of cars by lowering the NUMBER slider.\n"
! O2 R8 ^# d' w/ t7 F9 } "The setup has stopped.")
1 e& L1 p! |5 I* V stop; Q! L9 r4 B1 j6 ?/ r( x+ }
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 W2 r1 B! y1 r' t1 s2 ~ crt num-cars
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}0 H7 e! b- |' V0 d3 ~ setup-cars
4 A* G( m9 n3 z! Y! ?8 O set-car-color, _0 d4 ]' {$ _& u0 }1 y
record-data- \0 r3 S5 {+ X: l8 g. B
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;; give the turtles an initial speed9 r: M( Z! j2 Q& {) U) f
ask turtles [ set-car-speed ]
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9 E; ^ k. @' \+ w5 P' i reset-ticks5 l8 {7 P4 Y: |
end
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;; Initialize the global variables to appropriate values
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7 x9 {, a! G' ~( m; |3 U5 K set current-light nobody ;; just for now, since there are no lights yet
! X1 }, M2 W! r set phase 0
9 ? x, u% b! |8 D! g$ T set num-cars-stopped 0
a' i& n; e# @. u. y3 E2 h$ h set grid-x-inc world-width / grid-size-x
( [ j9 @( x( X3 c7 u- x0 Y set grid-y-inc world-height / grid-size-y5 R2 J0 m( T- z s* F, H
6 b+ n$ z# r% i! O, o1 f ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary R! r+ q. ]( {& |
set acceleration 0.0995 n0 j2 ?1 |% X8 |; z* F
end& ]6 A/ Z% H5 Q1 G
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
0 Z* a6 Y' m7 X% a;; and initialize the traffic lights to one setting& _4 J! s8 R# d$ L
to setup-patches
. t' F6 K* e8 |) l ;; initialize the patch-owned variables and color the patches to a base-color2 {% b! ^4 {+ s' T+ m' l. _
ask patches' c9 Q8 U/ x. e& D6 p
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/ H$ [2 [8 k; t: V4 N1 X* K( H0 c set intersection? false
! A$ }1 U/ g' u; {5 |8 r# l set auto? false- i" d' q4 z2 ~0 `, d$ c
set green-light-up? true0 e- [! u. k ?/ T. `7 y" y8 d
set my-row -1
" A W8 D0 q* k$ Q& i5 `; Z set my-column -12 r. @1 O" a) r' l b% S$ C, ?
set my-phase -1
/ `- w/ E5 \* F+ Z- Q set pcolor brown + 3# e; G% _4 m& O z$ z
]
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5 S$ v$ Q1 _' C3 ~ ;; initialize the global variables that hold patch agentsets
2 R6 n4 Q+ k$ P; l/ v7 F set roads patches with
! m2 k& ?9 ]2 W+ Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 `4 o1 N9 _( \& {
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! |8 e4 M3 i8 ^ set intersections roads with K8 M. G2 A5 z# W4 m, f5 {/ X. }
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and/ G) U! ]6 N3 @, x
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 W0 b7 u/ X& v! z6 ?) v9 C( E1 u. W
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ask roads [ set pcolor white ]/ D( ~& j6 k/ ^
setup-intersections
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Y: L, K( S# @' I5 ]其中定义道路的句子,如下所示,是什么意思啊?
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: j2 V x( r; ]' G! B% v [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
! D8 k2 `* y$ } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% j2 L; j- g4 r$ x2 f3 G4 D
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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