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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。
4 S/ ~5 f/ |% q5 A3 w! @netlogo自带的social science--traffic grid这一例子当中,
$ D( M8 F' a( {globals1 B4 T" X. L( E1 [, v/ w
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9 B# u' D7 v$ L$ `8 c* E grid-x-inc ;; the amount of patches in between two roads in the x direction
1 K0 D0 s5 M$ s3 U grid-y-inc ;; the amount of patches in between two roads in the y direction
3 t6 ~4 N7 I' i, `& g acceleration ;; the constant that controls how much a car speeds up or slows down by if
Y: v4 A$ L4 q0 G ;; it is to accelerate or decelerate
% B z4 w1 m' Q phase ;; keeps track of the phase! c% e/ D% e9 P7 h; @! z. Z0 k8 o
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure. l! |# _( I" W; [; N( S! J# @) M
current-light ;; the currently selected light' R2 e. U7 L" k- l- V8 a
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;; patch agentsets. R9 {3 x/ s. r, v# U( r
intersections ;; agentset containing the patches that are intersections5 W& |+ W9 c" |6 c
roads ;; agentset containing the patches that are roads6 t' o6 V2 j) a
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turtles-own
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% J" P2 r' ]6 `1 A8 U speed ;; the speed of the turtle" b) M5 P. \1 }1 J1 [
up-car? ;; true if the turtle moves downwards and false if it moves to the right7 ^- ?8 p/ N( s+ Z, _) i2 P O
wait-time ;; the amount of time since the last time a turtle has moved
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, i; m3 b/ X l1 J! T% N8 {' spatches-own: ?& R1 e5 t$ _/ ^, F0 h6 f
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& n% R: {8 b T' U; } intersection? ;; true if the patch is at the intersection of two roads; B# G7 z7 f9 I8 o( Z6 j3 U3 ]
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
# p% ]: O- X- \7 f: v' X L" N5 _ ;; false for a non-intersection patches.
% c% N$ I3 A! i my-row ;; the row of the intersection counting from the upper left corner of the
! V/ j% M) A$ O1 E" q& s ;; world. -1 for non-intersection patches.
) b: V- L" b- z9 ]" R8 B6 w my-column ;; the column of the intersection counting from the upper left corner of the3 j7 |" v) D! @: L- `3 ~
;; world. -1 for non-intersection patches.
/ J9 r/ Y' u# c C! S; w my-phase ;; the phase for the intersection. -1 for non-intersection patches.
4 O& {+ U f: q% c auto? ;; whether or not this intersection will switch automatically.
$ U; z. x- D0 `1 w0 E* w ;; false for non-intersection patches.2 Y4 x8 }+ x& x! E; E, F
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. {- h) j6 l8 g" c7 x3 c) t;;;;;;;;;;;;;;;;;;;;;;
& m. N( N C) k;; Setup Procedures ;;) q7 v3 b, i5 f4 `
;;;;;;;;;;;;;;;;;;;;;;
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0 Q: {& A% h Z. O& ]9 H- I;; Initialize the display by giving the global and patch variables initial values.8 U1 M% p, C) X, D0 d# T% K# N
;; Create num-cars of turtles if there are enough road patches for one turtle to
# y% A* F" F& ~4 E;; be created per road patch. Set up the plots.
: _$ i0 {. W: \6 Ito setup6 V+ J5 D* Y1 @: L. a
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setup-globals
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+ o3 C4 G' l/ _ ;; First we ask the patches to draw themselves and set up a few variables! v& k6 U& X" E
setup-patches: c( X5 ^6 M0 g, S2 @6 \- X: A9 S
make-current one-of intersections
: U/ w% b2 g; n# f) c3 k9 F* r label-current
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* o9 ^9 s, f* T1 f. U set-default-shape turtles "car"; C. n1 [: X# {9 A( ]! d, U
; M3 f0 h: M( i9 N3 P! }9 a if (num-cars > count roads)
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( E( ?5 S9 h. {( Q9 @2 E user-message (word "There are too many cars for the amount of "+ Y) [$ _6 q" n7 x- j$ r N# @
"road. Either increase the amount of roads "/ e) e: k3 J5 a1 t) ?. Y
"by increasing the GRID-SIZE-X or "
9 i \# h- {+ M" a. ]& I/ t "GRID-SIZE-Y sliders, or decrease the "
4 x! C' Y& x6 a( p6 U5 D "number of cars by lowering the NUMBER slider.\n"
: X6 ?% C$ b1 f$ [& p2 w7 b( O "The setup has stopped.")
. v) q2 P% c+ V4 Z6 u/ ]. ^ stop
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2 a' J) ^- X/ X; u1 y1 u ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" p/ y( U" W% ]7 _ crt num-cars
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9 P5 t% c9 F' u: E9 n$ E setup-cars1 \% J6 u1 s* w a; n4 i* q4 U
set-car-color
' h' f1 U: |' t: e1 m+ l& g5 ]# T record-data
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;; give the turtles an initial speed
0 d7 [; r. Q( ~. K0 b- S- j. S ask turtles [ set-car-speed ], O9 h1 l9 C- H, ? u+ e6 a
$ Z i5 k+ k$ Z( _4 {# ^ {/ d6 H reset-ticks
% ?1 J4 V |* q; a& f$ cend
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;; Initialize the global variables to appropriate values" ^* ?, D% h5 F. ]* Z
to setup-globals( ^: K. H& p7 [
set current-light nobody ;; just for now, since there are no lights yet/ r. I, T3 x6 b
set phase 0+ r9 t9 t7 Y; M, N) s3 p6 n
set num-cars-stopped 0
1 E3 t2 `3 ]! n1 c5 j set grid-x-inc world-width / grid-size-x; ]0 |$ b h3 \
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 Z& N8 E( ?0 H4 k" U; i set acceleration 0.099
" b! l) P8 @$ o& Uend
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. }8 t+ ^ n6 f* _- ~, \9 t4 ?;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
, e T* a$ M/ A2 Y. D* e6 [;; and initialize the traffic lights to one setting
+ w, Y) g8 T& N* Lto setup-patches
% O" g7 [$ K, G- p. n$ o ;; initialize the patch-owned variables and color the patches to a base-color- b9 K$ k! @4 t/ g' }, @
ask patches9 G) l: l: R7 q. e4 L. c) Y
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( P! _6 e" d2 l- v5 @2 i set intersection? false% t1 \ D+ @; i2 u; w) ^6 V% G* n
set auto? false( h9 K K$ M m/ x0 a5 t
set green-light-up? true
; M( Z; X& K) ]8 Q. b+ Y+ I/ g set my-row -1
5 V; P! @/ _; }4 k* ] set my-column -1
3 V% N* M9 Q. b set my-phase -1; K8 @$ K( z' K5 R" I
set pcolor brown + 3
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! x# G" \+ |; W% L1 e5 U% S ;; initialize the global variables that hold patch agentsets& d8 k; f$ L% [6 u( W( u3 K( J
set roads patches with
( v* p. M- ^0 o/ ] f/ J6 W8 k% D [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- A" K2 Z: F3 F. h9 v* W6 {1 }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ b+ U4 Y$ r% @! }
set intersections roads with8 V) w( p9 M/ E, f9 Y8 R% D
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and p- p& d( w1 U, s
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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P8 A- ?6 j/ V- a2 W9 u2 G4 p ask roads [ set pcolor white ]
! o( P( }- @, Z( N( ~$ `1 g4 F" e setup-intersections1 F U6 T$ t" `( q5 f U5 D
end
# i3 z0 ~0 u0 |9 L其中定义道路的句子,如下所示,是什么意思啊?8 K8 u: `+ v: Y$ T! |. K, x- E6 V
set roads patches with! u' X- T& P" o1 b- p
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. z4 N! d( D' v, S4 t/ P2 W6 E
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 Z. r' \; E9 B/ _0 n0 |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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