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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。7 E, I: T4 Q( [" Y: K) k0 { Q3 M0 ]3 ^) M
netlogo自带的social science--traffic grid这一例子当中,
K$ d- C, O6 m% T9 Sglobals
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3 ]" u4 r" i0 }6 Z! p grid-x-inc ;; the amount of patches in between two roads in the x direction1 U; c3 \% X& u0 p( i9 W0 U4 M
grid-y-inc ;; the amount of patches in between two roads in the y direction
0 `" t$ ^6 [$ _$ G acceleration ;; the constant that controls how much a car speeds up or slows down by if
( }5 t2 z9 {, o' { ;; it is to accelerate or decelerate: n+ o4 I4 `: b, X
phase ;; keeps track of the phase
0 e( N, Z0 V0 a& _! }& ~ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure$ F" {/ n Y$ ^5 |6 m5 \ ?& T
current-light ;; the currently selected light
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4 A: a5 z# m/ h. B4 j4 E: p ;; patch agentsets7 q) f- K: h- y5 a9 i, A
intersections ;; agentset containing the patches that are intersections. U: t# S) g3 [8 ?! l+ ~
roads ;; agentset containing the patches that are roads
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turtles-own
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speed ;; the speed of the turtle$ @$ l6 M5 H q2 K' H& l' }
up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 `0 B* v' ]( a. [! g wait-time ;; the amount of time since the last time a turtle has moved/ |0 ?0 d$ d" T$ ]
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patches-own3 h. H* n9 L! ?- n' G% S
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( F! P# C1 J& ]% Z intersection? ;; true if the patch is at the intersection of two roads$ ?/ {$ A( A1 x* N$ q, A
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
) T) s% @1 D0 N ;; false for a non-intersection patches.# @# x9 G$ C7 C6 F; ]4 P
my-row ;; the row of the intersection counting from the upper left corner of the2 b9 K0 n' |* D$ f
;; world. -1 for non-intersection patches.# }; r7 r$ s3 r( e7 z, ]
my-column ;; the column of the intersection counting from the upper left corner of the& @- H4 o- U; ^3 B+ f# N# C7 X9 @3 E* g
;; world. -1 for non-intersection patches.
/ h% T5 u* h( X( t# V4 d* z6 t my-phase ;; the phase for the intersection. -1 for non-intersection patches.
6 D" w! n+ F$ J5 e! l auto? ;; whether or not this intersection will switch automatically.
( D* U2 @6 L) F# ^4 }7 ` ;; false for non-intersection patches.& f( m5 W! _8 x
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;;;;;;;;;;;;;;;;;;;;;;
7 L& P3 N6 `0 `* W$ P0 \( l;; Setup Procedures ;;
# d3 F( k0 }8 p9 A;;;;;;;;;;;;;;;;;;;;;;# r1 M* o e/ J" f0 n% p7 _
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;; Initialize the display by giving the global and patch variables initial values.. D m! t& K$ i) B
;; Create num-cars of turtles if there are enough road patches for one turtle to
1 P5 g* }; e, J! V1 V;; be created per road patch. Set up the plots.
9 P' K1 `& m% F* E4 e, k8 gto setup
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) b! U) M$ k9 J# S, t setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
* c) \+ b: A2 a$ b/ @5 d y& } j7 a) H setup-patches& E: x G( I# f9 E! |! }3 G8 n
make-current one-of intersections; @+ G" J5 [. g/ P& O
label-current2 X2 C( g" u* p$ f3 k1 M* v
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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 D7 E& f/ ^2 [8 C "road. Either increase the amount of roads " j, W! I' \: K6 z8 q/ ^
"by increasing the GRID-SIZE-X or "* G$ v0 t& e; x1 o$ K! o: p; F
"GRID-SIZE-Y sliders, or decrease the "$ t3 q5 @$ V h+ q# \
"number of cars by lowering the NUMBER slider.\n"
- I% c! h; U$ J/ d' N3 c "The setup has stopped.")
4 r; p, N$ c6 F2 B6 w stop
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& M8 q9 W. I4 X( X; Y ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color6 {; u8 q; X. b F: O
crt num-cars
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setup-cars0 G5 j5 ]0 ^( M1 V9 q9 s3 g
set-car-color
9 a& Z/ k, F2 d/ L record-data
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1 ]' ^7 `: V' P) W! n- w ;; give the turtles an initial speed
/ ]8 D W& B2 ~ ask turtles [ set-car-speed ]1 ~# r( N, _' K' D. k- m1 [0 X
9 n, ~+ P2 o' S; S% \& O4 h5 I reset-ticks
' O, l5 ~9 m8 _9 m H' E8 J) i. uend
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$ Q/ V9 d, [) ?, ^7 ?;; Initialize the global variables to appropriate values
* ?6 R1 Q5 W1 o$ u" Kto setup-globals+ }7 r/ d1 ~9 |4 X
set current-light nobody ;; just for now, since there are no lights yet
0 V: G: ?1 i/ \0 N. ] set phase 0
2 f2 n6 b4 J$ m0 m set num-cars-stopped 0) Y$ n& h% W% X( K1 h% Q
set grid-x-inc world-width / grid-size-x, J+ k# `0 c- S3 k4 j
set grid-y-inc world-height / grid-size-y
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% k3 F( V) C/ I. R, n# m( V ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary# |2 E' ^. M, U, S1 n1 H
set acceleration 0.099
: L2 @: X: h* `0 ?+ Uend; ?4 _3 i$ K' r* u$ g* N
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,0 d4 O* C0 m8 V( S, f/ d
;; and initialize the traffic lights to one setting* K4 ^! t5 `- k6 u5 h# u1 P
to setup-patches0 E% S, p8 J2 _+ Y# ^: V9 h7 M
;; initialize the patch-owned variables and color the patches to a base-color" O. \7 [' Y7 p$ M3 B6 b
ask patches$ I! o0 O F, E7 {5 ?# q) P% T3 c
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set intersection? false
& m) t. X! Z' f- M- f- V3 R set auto? false+ e' k! x3 m3 T, o6 r) E
set green-light-up? true$ x$ K1 k$ m- G; h$ a! {
set my-row -1
! \* M% H- b- P' }9 o7 f set my-column -1
3 x+ ^4 P2 f2 f, ?; a2 Z set my-phase -1
7 c+ Z' z# R+ O# X; R set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets q% T6 _. r: {3 t' W5 y
set roads patches with
}4 M E) `, E0 @! \ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 h& f7 ~* E; J, a K5 ~
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& ]3 [. w/ ]: e! j8 F+ I. c
set intersections roads with
% y# C3 X/ k" F [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and$ W" s) y/ P/ C
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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8 A6 y% \( q) J2 k! z ask roads [ set pcolor white ]( B% T9 z8 e; H
setup-intersections
% H4 A. [0 K! S+ B# nend
* E. ?+ y9 G: x' }% Y( @* m其中定义道路的句子,如下所示,是什么意思啊?
. S' f N' c0 w set roads patches with: c7 D( v6 ^, W! v- C2 J, e
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ U3 c* r. Z0 I( T. `8 j8 M- H: ] (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 W0 T9 ^% |; m$ i' J8 \% f3 `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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