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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。
5 a& i! E$ |3 q3 @; l! g% Xnetlogo自带的social science--traffic grid这一例子当中,
! Z& b2 _. K) m* _) e* }globals
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- V1 m- B. z% t. O1 b grid-x-inc ;; the amount of patches in between two roads in the x direction
+ s+ l7 N1 O6 d8 R; @ ] grid-y-inc ;; the amount of patches in between two roads in the y direction6 I0 Q+ }! o/ L9 q
acceleration ;; the constant that controls how much a car speeds up or slows down by if: l P) Z- \$ U- `! N0 V0 z
;; it is to accelerate or decelerate) g; Y; N' f: t: z4 ~
phase ;; keeps track of the phase
0 v: j1 F( n* h2 O1 C num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure& s: v3 @& G% N0 n" l5 L5 R% C# }
current-light ;; the currently selected light3 s8 [) p% {6 ?6 R
" h$ u0 S2 I! d3 o' G/ c$ p3 M ;; patch agentsets
3 d: M0 j$ \6 q/ e, R2 v intersections ;; agentset containing the patches that are intersections; N3 Q) \ Y h2 c5 w6 l
roads ;; agentset containing the patches that are roads: b/ F0 Z: y/ c! c4 v
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7 D! `* i" Z9 ?5 u+ Qturtles-own. U5 b; h% n! l" t1 \1 d
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speed ;; the speed of the turtle
! k$ C$ R3 t' k up-car? ;; true if the turtle moves downwards and false if it moves to the right
) K, T5 f2 c& k# i: N2 o) t0 L2 b wait-time ;; the amount of time since the last time a turtle has moved+ Q2 F5 Q0 `- A& J
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) ~ v+ d D4 Epatches-own
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intersection? ;; true if the patch is at the intersection of two roads
$ z9 o; a; S$ Z2 Q/ ` green-light-up? ;; true if the green light is above the intersection. otherwise, false.* N- x) g) c8 ~8 H
;; false for a non-intersection patches.
+ R) s# i6 O7 K) k my-row ;; the row of the intersection counting from the upper left corner of the
: n8 N/ b E8 a- n8 P* F: f* ^ ;; world. -1 for non-intersection patches.
. v: X1 I& X8 h$ g my-column ;; the column of the intersection counting from the upper left corner of the
# H% E8 `0 g9 @ ;; world. -1 for non-intersection patches.7 ^: Y4 z0 q- N+ Y
my-phase ;; the phase for the intersection. -1 for non-intersection patches.8 D$ q$ R. A& E6 G$ n, s. X
auto? ;; whether or not this intersection will switch automatically., K: R, e: z5 }8 A; f4 E A
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;0 `% s0 ^9 Q( _1 e( _2 C- s P
;; Setup Procedures ;;# \0 X7 h" a- p. ]6 D
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;; Initialize the display by giving the global and patch variables initial values.4 N8 m2 }( b+ C0 g4 [0 i
;; Create num-cars of turtles if there are enough road patches for one turtle to8 V4 W. u L: v5 {& G4 }) Y6 H
;; be created per road patch. Set up the plots.
( U7 W5 b; d# x2 Vto setup J- g# s+ @0 Z$ j5 O) L5 y" ~
ca
9 g- {+ F: C. o. h$ A setup-globals, i+ t7 z5 ~3 O0 n& [" _' v; k& v
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;; First we ask the patches to draw themselves and set up a few variables
1 e% w/ H0 A) g4 X3 [& ^2 a1 Q( E& t; o setup-patches6 o) J4 J1 f9 }/ Q4 {- V# O! |) ?
make-current one-of intersections
0 C7 L4 M/ G$ J. H label-current/ R- L7 \6 L1 s7 ^# l) a1 y# `) N4 l
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set-default-shape turtles "car"& D7 J4 z9 {& G' R4 K3 @" I) t+ C: A
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if (num-cars > count roads)
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: ?; C, ]) N4 t. J5 W6 N' P user-message (word "There are too many cars for the amount of "
) ^8 k4 V4 @, j. o2 C "road. Either increase the amount of roads "* P8 \9 Q) s8 X6 L; Y- L- G
"by increasing the GRID-SIZE-X or "
, J* ]5 ]% p, o$ J4 R5 b "GRID-SIZE-Y sliders, or decrease the "( W" Q5 y0 l, x* [7 a9 `# U
"number of cars by lowering the NUMBER slider.\n"
, a! _# V+ A t `" q6 g8 Q "The setup has stopped.")
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
2 z" r7 W# c5 m' }" ]( H crt num-cars; F9 [5 L/ n- G! G
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setup-cars. ^- h3 D m* H7 [$ Y c: G6 R7 ]
set-car-color2 a& X$ W( G) J; s' U
record-data$ N" s: t3 X: z3 g9 ?6 ~
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$ j+ Z4 Y7 H4 K- e$ D# b+ O& v ;; give the turtles an initial speed2 r. Q5 B, f/ V
ask turtles [ set-car-speed ]7 P: I) N4 q& b2 s9 M' ^3 s3 F
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reset-ticks a' t1 |5 m# h" p* y. z) i
end
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' Q w* x0 k. w/ r' p;; Initialize the global variables to appropriate values# c* y" }: }5 a& i
to setup-globals
) x( f$ h- B, b( L. r set current-light nobody ;; just for now, since there are no lights yet
' r* G3 w4 ~9 ]& B T set phase 0 E& d! K/ c0 g; V
set num-cars-stopped 06 J/ f6 L( c- v1 o5 {* {
set grid-x-inc world-width / grid-size-x
. P2 s$ g! _0 }' A) @; _ set grid-y-inc world-height / grid-size-y$ r# ^' F) g& M3 a5 J! N! u1 u8 q4 |
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
; p7 t* U+ E/ R set acceleration 0.099+ F2 p* G1 x2 T( k8 X+ t% j) F% L9 y
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,7 R, W' o1 c6 B3 S
;; and initialize the traffic lights to one setting
: V& z# k- T5 h r. nto setup-patches1 T. E. J* B3 W
;; initialize the patch-owned variables and color the patches to a base-color& _& ]. J* u8 Z& t ?$ `; j
ask patches
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4 h4 d' v& h t7 L8 | set intersection? false: n v+ ]0 H; A/ F8 {0 @- I
set auto? false
C* _3 f. `# J: u- \- ? set green-light-up? true
$ ^! g( g" T6 F }9 b9 ?3 m5 K/ A set my-row -1; s: t w3 j6 B
set my-column -13 Q# l/ i2 h& a6 v# o
set my-phase -17 G5 `& G7 e/ ^. F1 u$ `
set pcolor brown + 3
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0 d3 U: v/ u4 i( J2 ~$ N- J" M ;; initialize the global variables that hold patch agentsets
" W7 C6 t( \; k- r* k/ Y+ p4 C set roads patches with7 [; O1 e) H2 w' R
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 Z& ?, [) W. \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ X0 o1 U# f+ W9 [2 g7 u4 o- H
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 G. ?4 `* Q/ ?) ^4 Y& J- _5 V# \
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ask roads [ set pcolor white ]0 {" n" i6 d6 Y9 u6 K2 r
setup-intersections) y& x) X6 y5 o" i6 w$ R" Q W
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其中定义道路的句子,如下所示,是什么意思啊?, K+ e; | @$ B B$ T
set roads patches with
! U' k1 a- t( \9 [- Y) I8 K [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
/ m3 g# _+ N5 o9 l (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 G6 l! ~6 ~ Q0 z! T* p
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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