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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。% p) O) M. l# K; Q) b- j, z
netlogo自带的social science--traffic grid这一例子当中,
5 t3 x+ u8 @. O; J1 e6 E5 r' Kglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction- r4 T$ c3 d8 |% g& Y( S8 H
grid-y-inc ;; the amount of patches in between two roads in the y direction3 p S: I) q* m7 q
acceleration ;; the constant that controls how much a car speeds up or slows down by if1 f& i8 z) e Z t1 h: B) s
;; it is to accelerate or decelerate
/ I. {& R2 `6 ? phase ;; keeps track of the phase: f( }4 `% ]' s! }7 f% ~! p# G i
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
+ M- ] h, F) ? ?4 d; U, N current-light ;; the currently selected light/ f. Y J5 X Q9 L+ Z7 j. i& ^
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;; patch agentsets
0 V1 R) D. [: N# q" ^7 b6 E intersections ;; agentset containing the patches that are intersections
1 P5 R+ P/ o; z roads ;; agentset containing the patches that are roads& F1 A1 J, c/ J! b8 o. Y! I& R
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& V) u6 Q' }3 ?, ]turtles-own
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; \* u( h* u8 C7 y3 y9 K0 z speed ;; the speed of the turtle+ `+ n! p. x# K9 i/ D3 L1 x
up-car? ;; true if the turtle moves downwards and false if it moves to the right+ m! r: u: ~( i# y/ O
wait-time ;; the amount of time since the last time a turtle has moved9 r. Y. R& n; V1 F& g
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& E: Z) X" Q! a# d8 D# ^3 W7 vpatches-own+ ]0 }! i8 t; h, s
[
# L* N B* P( j$ R7 G \ intersection? ;; true if the patch is at the intersection of two roads. h, }: Z1 C( e }1 g
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
; \% q* Y8 x# ^9 F/ E ;; false for a non-intersection patches.# s/ Q) V" x2 v8 J% s( K4 }; r- L
my-row ;; the row of the intersection counting from the upper left corner of the) `5 D" G. v; w3 k
;; world. -1 for non-intersection patches.8 i! w$ I6 t' m7 Q+ ~0 O' H
my-column ;; the column of the intersection counting from the upper left corner of the
& \$ S- I4 L0 ^7 V ;; world. -1 for non-intersection patches.: q' L+ i+ y) T7 u
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
" V2 a" |0 E5 X$ v" `: J, D6 i auto? ;; whether or not this intersection will switch automatically.& _! z3 @% V, Y) x2 c
;; false for non-intersection patches.1 X9 P v7 `8 r1 u7 M6 b/ W
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;;;;;;;;;;;;;;;;;;;;;;
# r# q# t9 f/ O7 @7 g;; Setup Procedures ;;* Q$ v+ _) T. t- ~( C
;;;;;;;;;;;;;;;;;;;;;;6 D Q. L( w% e
8 D7 D& J9 `8 Y7 k;; Initialize the display by giving the global and patch variables initial values.
5 O: [$ V# l4 }- t; E- e$ l;; Create num-cars of turtles if there are enough road patches for one turtle to
# r' `! I( B. A; U;; be created per road patch. Set up the plots.
3 A2 d- V7 V7 {to setup
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7 L1 ?, V; e! u7 a. f setup-globals* f! u/ |) K$ S5 o1 R' M. `
4 Z4 I$ x) r6 J( [ ;; First we ask the patches to draw themselves and set up a few variables
" s( k Q( n8 [1 {4 E( b setup-patches! T2 O. U; G/ E/ c2 L) k* G! N# C
make-current one-of intersections) R6 d" x q: |+ }0 O
label-current
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3 D( k! b2 z" G: b6 b6 S9 \5 \/ z set-default-shape turtles "car"
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if (num-cars > count roads)
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8 D# I3 {8 J& a4 D' a% g$ B, M user-message (word "There are too many cars for the amount of "6 M C! T3 w- u3 k$ \
"road. Either increase the amount of roads "# ~) K9 I+ J* F
"by increasing the GRID-SIZE-X or "
* |# f @1 v; h5 k; |' |' | "GRID-SIZE-Y sliders, or decrease the "
4 L5 Z o6 J+ [9 K* L% s "number of cars by lowering the NUMBER slider.\n"3 g* G; X" s- y v
"The setup has stopped.")
+ o5 g4 L7 H6 ?7 z stop
+ m2 e! w+ a# b6 \" _7 `6 F ]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
8 K% x5 @! z- Z2 |9 k crt num-cars/ z+ o T! }7 G4 y8 n5 G) O$ ~
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! r& v) ?1 \' h) R* C, `7 w setup-cars; T" X- a1 U1 k' T
set-car-color8 d3 P8 R& B1 r u) w
record-data# z, h- ]+ ]) v$ ?* F
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;; give the turtles an initial speed: h4 y$ ?7 Z3 b% A: I8 i' [: v8 M$ d- A
ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values4 B. W& l! ]6 Q% G+ n# J% i
to setup-globals
: q4 h, R% p1 Y set current-light nobody ;; just for now, since there are no lights yet
' ~" J* m! a8 w/ S" P set phase 0/ O& Y7 ?: X6 {/ _. @- x* ~( L
set num-cars-stopped 0
, ~+ J f; Y3 e set grid-x-inc world-width / grid-size-x; H# ~; i: e, `$ U" Z$ l- l
set grid-y-inc world-height / grid-size-y( `) D# ^3 b& G# e
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
$ ]( t, E% K% k$ f1 S- N1 @ set acceleration 0.099
2 y7 R% @& C1 nend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,9 n' q5 ]# z' Z5 ^" z& p
;; and initialize the traffic lights to one setting
1 U$ ~" g1 U4 ?! S! c- rto setup-patches( S U! l, a M9 H
;; initialize the patch-owned variables and color the patches to a base-color" l4 S* o' L. T, ^8 o3 D5 c
ask patches( |) @ k2 Q8 q# s
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set intersection? false2 y9 E N4 s( x! _4 I) Z- G X
set auto? false
. _' D4 D; @9 w% `& V8 J" i) ^ set green-light-up? true
' f6 J+ N8 L4 a8 B' Z. w set my-row -1
# J& ?7 F1 d; O set my-column -1
, D2 B2 q8 D% d/ ~ set my-phase -18 J1 i) w2 ]) `; Y% W# a
set pcolor brown + 3
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: J2 i( d& N) ]- q1 s5 y ;; initialize the global variables that hold patch agentsets
1 ~9 c( y7 i' `, B set roads patches with
5 H [9 X. D$ I. |8 C [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' ~* Z ?% y z/ O, Q( O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, _$ u) G1 Q" E" @) |4 {7 Y8 i: | c set intersections roads with4 \% d' e4 L4 O, M$ } f M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
8 O* G8 X8 v& r5 N (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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& y! t; O" K2 ~5 q ask roads [ set pcolor white ]
$ T t7 C, _& R6 }9 @; [ setup-intersections4 L. Y3 y* a! s2 l
end
3 v2 E/ j) }1 u! m% v$ s其中定义道路的句子,如下所示,是什么意思啊?4 E1 u7 A( c' t0 Q$ P* m
set roads patches with
/ o5 {' K T4 F' K/ Z" Z4 q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- K' M& }4 O' } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* i6 F& C( o" z& \: Q
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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