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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。1 ^/ l) O" t: x1 d8 k8 `. L5 C
netlogo自带的social science--traffic grid这一例子当中,
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, X2 ^. d/ V& H( f, k* ` grid-x-inc ;; the amount of patches in between two roads in the x direction
. }9 M( C& ]/ C1 ~- g+ J grid-y-inc ;; the amount of patches in between two roads in the y direction4 u* c7 B E; Q6 X# P( Q+ n
acceleration ;; the constant that controls how much a car speeds up or slows down by if
5 Y0 V$ C" @ Y @7 P ;; it is to accelerate or decelerate
/ ~* _2 \+ n. \) F0 Z. X1 ]7 P phase ;; keeps track of the phase
4 D$ t3 {* o% ]6 N# T% p+ t& a num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure/ K% a8 ^, H6 C* ]! A/ j
current-light ;; the currently selected light7 x9 a4 U; T8 j8 s& Q: a! F, E' r
' Z# q/ g# G q8 }+ L' D2 }- k' e6 h ;; patch agentsets! @" Q, J" Y3 ]# D5 d% i
intersections ;; agentset containing the patches that are intersections! Y8 Q: R9 I6 y4 v
roads ;; agentset containing the patches that are roads* m9 g0 P0 o; g- a6 ]$ q
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turtles-own
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speed ;; the speed of the turtle
6 |% d9 b% c. X& ~ up-car? ;; true if the turtle moves downwards and false if it moves to the right
' Q" f7 c7 n; c4 G# W" \1 p wait-time ;; the amount of time since the last time a turtle has moved
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* t, H4 K5 m0 R. C4 y0 Npatches-own& H% I5 `: i Z( m/ f( T% z. Z
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intersection? ;; true if the patch is at the intersection of two roads
& X& }0 W6 ^% f2 {) h green-light-up? ;; true if the green light is above the intersection. otherwise, false.
0 R- ]" l2 k" t/ C1 _: j1 S% ~ ;; false for a non-intersection patches.) C. V3 S7 m9 S' X# x. Y
my-row ;; the row of the intersection counting from the upper left corner of the" g1 l" h- X8 H- i; T0 ?
;; world. -1 for non-intersection patches.
' o5 S- o' M3 u- Z my-column ;; the column of the intersection counting from the upper left corner of the
4 ?+ M: _1 F R0 w: L/ G5 h7 S" h ;; world. -1 for non-intersection patches.; c8 B* A" a' k7 @6 X8 A3 Q
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
! z+ \ [ l2 `/ H auto? ;; whether or not this intersection will switch automatically.
I! y# }) W# C. r; X ;; false for non-intersection patches.
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4 m8 v0 G! {1 E) l0 g0 W;;;;;;;;;;;;;;;;;;;;;;1 ^& Y1 E, Z+ X5 ?
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.+ n6 V1 \$ g m7 M! }
;; Create num-cars of turtles if there are enough road patches for one turtle to! F2 [% X9 j1 ~; }( m3 n1 Z9 v
;; be created per road patch. Set up the plots.
; |8 E1 p( `% v6 m" N9 qto setup/ |3 P( c+ D9 {- a, X5 Z! N0 A
ca
4 Y. C+ z9 C* Q setup-globals
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: I4 W4 p" U2 G1 r8 ~% Q* Z ;; First we ask the patches to draw themselves and set up a few variables
0 U" Y! w# R, Q7 v setup-patches
9 y# r3 a; l9 |+ C make-current one-of intersections
i8 L/ A1 ]) i( x# A( @- i label-current$ ]5 V/ d+ j6 a+ V7 w+ J
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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 "6 J7 X& `" ]/ C) u" h: ]# Q P
"road. Either increase the amount of roads "3 ]- X* p r* D$ i4 ^% T4 {; Y8 D
"by increasing the GRID-SIZE-X or "/ @) W& I+ M7 B- H
"GRID-SIZE-Y sliders, or decrease the "6 V: O, w1 D/ f- D: @) f
"number of cars by lowering the NUMBER slider.\n"# N* u/ \0 X; E: s) [
"The setup has stopped.")
/ ~" ?' L; k# M! ]/ y) O2 i stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
$ A' w. r; {1 e" X crt num-cars/ o+ n) d6 F$ P$ J
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4 @! Q2 R. y9 W; B+ Z, f4 z setup-cars( x+ E0 e' v$ v5 \; K
set-car-color
( |- @7 p/ N' ~+ u record-data
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;; give the turtles an initial speed7 I6 x" E* g" |& m
ask turtles [ set-car-speed ]
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6 B, B- ?' `5 k. p- J6 L+ V, m reset-ticks
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{7 y- {7 f& i7 y;; Initialize the global variables to appropriate values7 v3 V' g; }2 r
to setup-globals
5 F8 y, a; {' ~1 l% c9 P set current-light nobody ;; just for now, since there are no lights yet
. e1 n/ R$ U3 [% K( N set phase 0
* t; I1 r1 E' w, J( U set num-cars-stopped 0+ G$ A7 w$ b6 S
set grid-x-inc world-width / grid-size-x+ G/ D* B6 p) w' @9 f
set grid-y-inc world-height / grid-size-y# H: _5 |/ k9 x1 N U
3 I% ?' C& k& Y& d ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
* D- p3 @- A) p$ D' X: t set acceleration 0.0994 F/ ^9 x4 c- @, k1 l0 @
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 g- ^# w/ {! s4 G, c3 { O9 J;; and initialize the traffic lights to one setting# p; F* i9 C) h, `: c$ h+ M ^
to setup-patches
6 T: W) s7 u% }+ ~( L) d7 x ;; initialize the patch-owned variables and color the patches to a base-color( M$ L, [: L+ S1 v; w1 s
ask patches. C; @# x8 j E
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$ }$ t& p2 g9 t2 f" |* s set intersection? false
$ S, b b4 y" n5 t- N0 u set auto? false# T& ~; t- P# Z. ^+ |+ Y
set green-light-up? true
0 O% l) z- i% |; M/ @2 d set my-row -14 G% S7 L* t4 m! h, @7 ^5 ~
set my-column -1
; d, _$ @! i" { set my-phase -1
# F4 |. {+ s8 E) H" p' h set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets- Z# y1 ]: j* \' p8 Q2 e j
set roads patches with* `. Z* T; u1 g R* ^1 r
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
O8 [7 Q l$ g (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. c9 L9 z2 |$ S" D% c
set intersections roads with1 y/ T/ m+ F* p; E) T* l: P9 M6 M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
5 P$ U# n3 W |& b% x! Y (floor((pycor + max-pycor) mod grid-y-inc) = 0)] D q1 v( K& ?. _
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ask roads [ set pcolor white ]& n Q& [! H: {
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?* |. q, U1 `8 B1 a0 `
set roads patches with
' O3 }8 K; @' t# B% @2 I( ~, j [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) t/ |8 c; e1 c. R$ k- f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; r/ z8 M, m" J) ~, R. q, _' I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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