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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。; C( {3 k% ^9 \3 N& Q1 _) X# x
netlogo自带的social science--traffic grid这一例子当中,/ G( O( s+ ?5 Z7 i4 @
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction- X: i/ Y0 K& j7 r) {
grid-y-inc ;; the amount of patches in between two roads in the y direction
' w# n3 ]( m6 m9 [ acceleration ;; the constant that controls how much a car speeds up or slows down by if
! t( k6 f8 {6 | ;; it is to accelerate or decelerate
3 H* u+ t6 d4 S' D9 R phase ;; keeps track of the phase
3 K. n5 z1 X u num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
$ P' C8 k! |2 Z; w current-light ;; the currently selected light
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- ]7 Z0 u2 x$ B- m2 a ;; patch agentsets n: K7 q. u; K b: U/ ~2 ]
intersections ;; agentset containing the patches that are intersections
! D o1 P. ^/ e3 x0 [ roads ;; agentset containing the patches that are roads
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) W/ F( }6 h+ o' f' ]turtles-own
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speed ;; the speed of the turtle7 s; ]1 S- D. @3 B: D0 ~+ }
up-car? ;; true if the turtle moves downwards and false if it moves to the right# {1 L+ T2 A# L+ ]: D6 l
wait-time ;; the amount of time since the last time a turtle has moved" Q: z* D& ]5 M& [" ^
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patches-own* c6 Y" F) o W; m4 o* H" q
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intersection? ;; true if the patch is at the intersection of two roads" n( K8 l7 p* z* a3 c8 `
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
& V& w5 ?/ O0 B ;; false for a non-intersection patches.2 `: ?" q3 `! g d8 E+ B
my-row ;; the row of the intersection counting from the upper left corner of the- P9 L/ T3 m F0 |$ r
;; world. -1 for non-intersection patches.2 z7 T: _; J8 P/ Z5 F0 z) e$ e
my-column ;; the column of the intersection counting from the upper left corner of the! n( h# ^+ T4 G; ?! D
;; world. -1 for non-intersection patches.8 ^" e( `: U4 {1 D0 b
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
* U* B$ a# m- Y% u5 k, F auto? ;; whether or not this intersection will switch automatically.
& u7 i6 y \3 G# m+ w v8 N. j! ^! ` ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
2 s9 @+ h" c* d6 h) n; };; Setup Procedures ;;+ V% G+ ~! z5 }- a* G: L
;;;;;;;;;;;;;;;;;;;;;;0 D9 m. a- G4 q7 s! j7 y
5 V' K* j! C7 [- g8 Z& I# H;; Initialize the display by giving the global and patch variables initial values.
$ F; S0 H) Q/ w. J3 \9 F;; Create num-cars of turtles if there are enough road patches for one turtle to
7 j) g4 B# P9 E/ S0 W;; be created per road patch. Set up the plots.3 G5 c+ m% v/ Y3 G4 h+ E4 Y
to setup3 P& S# w2 z! m) n5 }- c* n
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setup-globals+ i+ _( e! k8 E: Y8 h |* N) o: G
- U. h+ H( E% T( o( i A ;; First we ask the patches to draw themselves and set up a few variables, N- M1 G1 w( j: ^( a
setup-patches
! V3 S- L) w7 ^/ A: Z0 w, w make-current one-of intersections+ F: L% }( S: I7 K/ i9 r: S. }
label-current2 z; U/ a7 C p5 I) P* e, P
# e8 v9 n! V7 z5 k set-default-shape turtles "car"" t7 E3 _% e1 q, W) h t# a
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if (num-cars > count roads)1 i; m: C" D+ f3 V% |" ]4 q' {$ T& G
[
' j& I. ~1 g+ V" e" W& J user-message (word "There are too many cars for the amount of "
?. V/ M N% g1 Z "road. Either increase the amount of roads "
' O' k3 x' Y& L# E "by increasing the GRID-SIZE-X or "- t, o& {. h+ D( o& k: J; Q W
"GRID-SIZE-Y sliders, or decrease the "
% _2 d0 L& S6 `- | M% w# H "number of cars by lowering the NUMBER slider.\n"
" o* x/ F# A6 y8 i "The setup has stopped.")
8 {) p; I5 J c4 g+ P0 g; M stop- p, P' h2 N7 n
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color" E% f, |3 ^ D z5 D
crt num-cars
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8 L- e. s6 F/ t I) y2 L setup-cars
& G4 }' h$ {! i: w' \$ z$ ~* t set-car-color% a. U1 d% \) O5 D6 _3 z. U: T+ ?
record-data
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3 [# z' Y! I- u" L, f ;; give the turtles an initial speed- b/ Z# P. i2 s* J$ N
ask turtles [ set-car-speed ]2 i; n/ `' }" _3 R+ c: H" |1 f
$ X$ Q" {# u) b) H( k# Z reset-ticks$ N) D \8 @ P
end# D2 @- M- ~7 O. i$ {7 S/ g$ `
! r- G& E1 {; x: G1 D! U;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet! F* q8 O$ [" v. P `; \( X
set phase 0
2 | X! \6 ?; X+ ` set num-cars-stopped 0
; m$ h2 w7 H) c6 y5 J set grid-x-inc world-width / grid-size-x
6 h( U. J9 a. e3 Q+ u set grid-y-inc world-height / grid-size-y- ]4 Y" F* J7 X$ z5 K/ O* c
6 C- c( W- G) [' ?2 b7 D+ d: m6 z ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
- M/ c& q! C1 Z set acceleration 0.0999 Y( i( i0 J% ?' c
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,. s) h3 M% X- h6 ?
;; and initialize the traffic lights to one setting5 S/ _, d9 ` q+ W
to setup-patches1 A" d3 U0 V- v: p) G
;; initialize the patch-owned variables and color the patches to a base-color
5 f# D5 R9 x/ S3 _. h* I0 y( w ask patches
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. j% I) D0 h# m0 B5 i. L& ` set intersection? false7 q: ^* J7 C* p" J) `4 O; @
set auto? false
) {1 M' L+ Q3 f; ?" B set green-light-up? true
3 A9 N) E# c& M( H3 E2 Y$ ] set my-row -1; f( ~. O. p9 V# J
set my-column -1
& Y' i" G% {) D9 j1 D/ J set my-phase -10 X3 F. V2 a1 L3 K$ w/ ?3 C
set pcolor brown + 3- |" `. y m$ i2 ~
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;; initialize the global variables that hold patch agentsets
$ r+ z6 {" E( a' C7 O set roads patches with$ l" v1 i' d1 b. A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 f; d. E3 L; V3 Y n" ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
+ G% |, J, u/ X/ ? set intersections roads with) [" W. Z: [4 F0 f3 [
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and2 A- [9 ^0 G; m3 P& Z, s5 |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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9 x- X0 [5 V3 \ ask roads [ set pcolor white ]- G6 P3 T' w5 X1 q
setup-intersections$ v: P2 b9 ^; M' W" Z& S
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其中定义道路的句子,如下所示,是什么意思啊?
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+ s# Y7 u& b: m1 g" ^ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 Y1 _# d, c. G" Q) y- ~* j
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 R8 ^6 E; w4 d1 x2 t
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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