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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。
; I4 J# m2 {( Z; o* lnetlogo自带的social science--traffic grid这一例子当中,
2 w0 V3 A/ J0 H6 z( V0 E$ p# Uglobals
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+ n4 z0 w9 J& T0 E# D4 A) X grid-x-inc ;; the amount of patches in between two roads in the x direction
4 ]5 ?+ Q8 V$ c; ^1 n8 | grid-y-inc ;; the amount of patches in between two roads in the y direction7 D+ ?0 W! D' ]% W- ]
acceleration ;; the constant that controls how much a car speeds up or slows down by if; P, m2 ~5 J7 @
;; it is to accelerate or decelerate
3 v. o! k! K @- ], B. k phase ;; keeps track of the phase2 F- `2 m) C( E( g% K, h* Z7 M
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
& t8 T! N$ G x8 F current-light ;; the currently selected light
' y) [( x1 J+ w5 v0 K4 k' {
, p4 E# Y! c0 K3 t/ w ;; patch agentsets6 r! |7 G1 f1 u9 D# M# }/ c
intersections ;; agentset containing the patches that are intersections
9 } W' y: t, I' i' Z+ B roads ;; agentset containing the patches that are roads: V# N# I( G7 ~
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- d7 v: ^' @$ i) pturtles-own* \, [( @/ m4 C8 M! s/ W" @
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" ]2 _5 R& \$ N9 S4 c. m9 e2 g speed ;; the speed of the turtle) b$ r% g1 A8 I1 p
up-car? ;; true if the turtle moves downwards and false if it moves to the right% u, d0 I) j; K2 X) A# ]
wait-time ;; the amount of time since the last time a turtle has moved+ ]5 X& b( `, ^/ t4 t
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
' T' v: F) Z# B: t1 x+ b green-light-up? ;; true if the green light is above the intersection. otherwise, false.- W5 j5 x1 M9 x1 X
;; false for a non-intersection patches.8 [" D& \2 x% _6 a# b
my-row ;; the row of the intersection counting from the upper left corner of the
; u8 ?" G7 {$ d( B/ s% D7 c; k ;; world. -1 for non-intersection patches.
# H! ^( ?8 A m0 k9 |# _8 F my-column ;; the column of the intersection counting from the upper left corner of the+ x1 V: h* V- V3 _6 C, g% U
;; world. -1 for non-intersection patches.
7 ?6 O' D0 R1 q' Q" }- s) R' | my-phase ;; the phase for the intersection. -1 for non-intersection patches.
% G( | l8 n8 [8 O4 m6 b# k auto? ;; whether or not this intersection will switch automatically.- {% L& ]$ L3 U7 N
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;3 z0 P3 r/ T* w
;; Setup Procedures ;;% ]! J7 O1 C2 H3 x
;;;;;;;;;;;;;;;;;;;;;;- Q m+ p9 y% M6 T4 m) `# U
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;; Initialize the display by giving the global and patch variables initial values.
& s0 ~& m4 Y2 N+ g* v;; Create num-cars of turtles if there are enough road patches for one turtle to A( u% U9 h8 k- O$ w
;; be created per road patch. Set up the plots.
" Q8 ~( l/ l, i$ a% o) I. G( K; zto setup/ ^6 }& H X1 S1 R1 C+ n
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setup-globals
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) y% L' h; Y6 O: Q" s3 s" D$ a ;; First we ask the patches to draw themselves and set up a few variables ^% G: `7 m8 Y6 X# u8 H( r+ |
setup-patches
4 D/ E# [0 @! J4 \* }$ ], A make-current one-of intersections/ n; I& R2 b* V/ @
label-current
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: M) M1 R3 Z6 x1 w: r5 M set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
( _7 S* _# r: N/ H+ l "road. Either increase the amount of roads "
' Q. Q0 F/ o# j "by increasing the GRID-SIZE-X or "
' k6 U; `9 v/ ]" l' D* T "GRID-SIZE-Y sliders, or decrease the "# [+ v& j L' V" v1 ?! u$ D, o
"number of cars by lowering the NUMBER slider.\n"
- I2 T7 _: A6 a5 Y0 r, N3 Q "The setup has stopped.")/ w& c) n' [5 T/ H
stop) |+ J4 O- D Z' y
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~) T- c/ W# `3 a2 p& H: g/ @ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, e- {7 z1 Z# [# c5 l crt num-cars4 M) N$ T9 r3 G$ f0 i; {3 p
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setup-cars
0 M# K4 j0 ]7 L7 g set-car-color! Y- |% d* p" a. C7 K
record-data
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;; give the turtles an initial speed) [" r0 c- t6 a8 i: G6 I) j3 q* F
ask turtles [ set-car-speed ]
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J) T( p: `7 V& m. N, K reset-ticks6 e/ e* d* ` y2 u1 _
end
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;; Initialize the global variables to appropriate values9 c+ J% V7 v- ?; M( k7 s
to setup-globals/ o9 w# ?7 O( k! u. O% Q
set current-light nobody ;; just for now, since there are no lights yet
2 }9 l2 C8 x* @0 | set phase 0
: y/ Z& o4 L: G1 a x0 t7 Z }1 L set num-cars-stopped 03 y! H4 W5 _- w# J0 I. ^
set grid-x-inc world-width / grid-size-x
# A1 }; ^9 }0 I. c9 B8 f' l 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
7 Q" I# l: N m; R b' h; ]8 _( i6 b set acceleration 0.0994 c' @5 k8 L7 e( H
end* R* a+ ?4 H) |4 l/ r9 Q1 F
" M5 L* G; Q0 X4 }6 {- T7 t5 B;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 e( V5 A: n9 M9 A$ | x9 R
;; and initialize the traffic lights to one setting
! F6 j% t+ C3 X7 Z! z2 F; z, mto setup-patches
, o' x, q) E: g$ P6 Z( d& K8 k ;; initialize the patch-owned variables and color the patches to a base-color
, a" H- V- C3 ?& J3 y ask patches) L$ ]! ?* g, ~ x1 t# P& B
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set intersection? false v' ~1 c5 e$ {2 n, _1 x
set auto? false" l3 [' K0 q3 N: o2 E; ?
set green-light-up? true
( ?2 p4 x' U, r3 n9 ? set my-row -1
6 L+ m m4 F+ R c% _1 V set my-column -1; {2 N( L. J9 C" c2 I4 \# [+ d
set my-phase -1
# X3 a( y, I7 d9 ^% l" D set pcolor brown + 3$ s( C5 V4 H; n( M8 K! `0 S- t
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;; initialize the global variables that hold patch agentsets s' p7 {1 ^- B7 ^
set roads patches with7 R: c! o8 J0 a/ h5 _
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# ]0 u/ e k# `$ `( \" {, _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]% E3 k, C: f0 F. j4 _( h
set intersections roads with
2 `0 f- I' j( f0 D" } [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" K9 |5 Q& d( m/ X* t3 a, r (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& w* x8 ~3 v! i) c- s: I3 n$ z% F
3 A* Q) L6 J* l' p ask roads [ set pcolor white ]
5 T% Z2 v/ l8 H setup-intersections- p" F/ q7 j6 l' G( D
end
3 h. u# Q( H/ T7 Y其中定义道路的句子,如下所示,是什么意思啊?2 m6 v, Q$ ^, @, e0 c
set roads patches with
9 Z$ \1 o$ M" B9 n+ f1 Q8 T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
O# F0 J0 _, ]7 R x3 | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 d: T2 C1 U! I% ?! R
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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