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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。0 z8 T* T4 T" Z; d
netlogo自带的social science--traffic grid这一例子当中,2 {# W6 ?2 ^& T9 p7 h& f1 i
globals
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3 X8 i0 u4 e f: @! ^. z grid-x-inc ;; the amount of patches in between two roads in the x direction8 S% j( v& k) q8 A8 J2 J+ J# u
grid-y-inc ;; the amount of patches in between two roads in the y direction
1 ~1 A4 w# v4 a9 x3 ` acceleration ;; the constant that controls how much a car speeds up or slows down by if6 \7 l& h: G1 A8 f# K
;; it is to accelerate or decelerate
2 t8 B) Y1 C7 j; J$ G) I phase ;; keeps track of the phase4 t. k5 C: d$ T+ n/ H
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
( }- Q$ y4 @8 Z7 s3 o! }% k; d3 b3 \ current-light ;; the currently selected light& |2 c: @; x/ z9 N8 K
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;; patch agentsets
4 D) \. T6 J) C' v$ H intersections ;; agentset containing the patches that are intersections t9 ^2 {4 [3 d, ?7 C: B8 O
roads ;; agentset containing the patches that are roads
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1 B1 C+ m3 \- d2 @turtles-own0 f! @5 D" \; [$ i( C% k
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speed ;; the speed of the turtle, \* o/ m4 R: v! Y2 J
up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 b+ J) T6 X1 T# L, c5 Z7 O0 x wait-time ;; the amount of time since the last time a turtle has moved% |$ Q& \2 K) J% i3 x
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. K& N- w6 W x" _8 D1 g( B% ]8 L4 dpatches-own# J4 Q9 j0 }! b# J2 M
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0 k% r1 p) v# T' K' \5 Y2 N- U intersection? ;; true if the patch is at the intersection of two roads# P& V3 A4 B5 s. ?+ Z/ G e3 U
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
8 @6 J. ~1 @7 b% R% f. A ;; false for a non-intersection patches.$ `4 {( K1 d( q0 ^
my-row ;; the row of the intersection counting from the upper left corner of the
; b" ?9 e. {% m4 R ;; world. -1 for non-intersection patches.& o2 L+ e4 ]" p6 Y
my-column ;; the column of the intersection counting from the upper left corner of the
# s* X4 o* h" ~+ ^: w! |; M ;; world. -1 for non-intersection patches.
7 V0 J+ _6 D' G [: K4 o3 Z my-phase ;; the phase for the intersection. -1 for non-intersection patches.4 }/ C4 z: f+ ~9 c
auto? ;; whether or not this intersection will switch automatically.5 z! F/ g1 j$ l4 K: C
;; false for non-intersection patches.6 l2 k( i E" ^. D
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# o- n* o! K$ g" F8 a; b+ E2 h;;;;;;;;;;;;;;;;;;;;;;
4 I p! F g5 W' l;; Setup Procedures ;;* {( G7 B0 c4 F, {% S3 w) o% |
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
` C; ]4 r( N, G# J;; Create num-cars of turtles if there are enough road patches for one turtle to5 @" ~/ m6 y/ A/ P4 X
;; be created per road patch. Set up the plots.
# ?" a6 r3 U0 N2 @/ {to setup5 V. Q. ^% `) c9 V2 F! E
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables( G* D& }# \" F- v
setup-patches$ J4 P; |: a8 K; y
make-current one-of intersections8 @& ~' _6 n9 A6 _" K
label-current2 |7 \6 N: a( M# B% L9 _, Q0 S
! x. z7 o$ }7 U( Z4 p set-default-shape turtles "car"
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if (num-cars > count roads)& g9 _) B9 [# u0 X; Z* B' u; c# U1 k2 ?
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4 _8 D. c8 r5 l( O+ `! F5 | user-message (word "There are too many cars for the amount of "
* {" D) [! {+ E: ~: F" `9 y- d "road. Either increase the amount of roads "
( t1 p( S3 b8 X7 r1 L- T' P "by increasing the GRID-SIZE-X or ": ~* t! x D# W7 V6 |3 @7 f
"GRID-SIZE-Y sliders, or decrease the "2 J+ u; k+ q" p/ z6 {. p1 w: B
"number of cars by lowering the NUMBER slider.\n"
# ?! o1 I* k" ~* ? "The setup has stopped."), M/ m) C0 A- h& p& a+ c
stop0 t1 i& m( }& j' B/ d9 @. X
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0 L) { `8 g7 x) v& t. ~' C ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
) R. }2 l8 T( n) j crt num-cars
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K8 k- X- v" V7 U* V$ H setup-cars
2 z) L- Z* D' x; ?, V: Y C set-car-color
& u5 ~% u7 M: Y8 ~7 e; K0 O record-data
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;; give the turtles an initial speed
* s0 c5 G4 P$ K/ h6 | C ask turtles [ set-car-speed ]% N3 e! [2 q. v/ {' a* R4 r
. B) A* ~" O9 G- U8 l reset-ticks V- c. n# s' ~ E; M5 p$ g
end
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- w6 `4 y( Z B! C, E0 \$ y, f;; Initialize the global variables to appropriate values0 _' T( |2 X# x: l) M3 h! [
to setup-globals
% l- s! @! A' _; |5 j set current-light nobody ;; just for now, since there are no lights yet
2 G% b5 B7 r+ S8 T set phase 0
/ ?2 B, Z/ [: y set num-cars-stopped 0 L. B+ Q& ? D7 h
set grid-x-inc world-width / grid-size-x
& ?. I4 e' K* Y. H! p3 t 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
* ]' w5 \. V4 N0 E) c0 } set acceleration 0.099
3 q- m' u/ G& gend
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3 K' y: w" L" f/ m;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' b9 n* x7 k. O @;; and initialize the traffic lights to one setting
/ I* n+ @% a: P! h+ Bto setup-patches, I. E* s, [( `
;; initialize the patch-owned variables and color the patches to a base-color1 g+ s3 @! p" {6 W$ _! s _
ask patches. X3 \) f$ y$ i/ ~
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6 g2 _! p" E, H+ r set intersection? false# ?8 r# R4 D1 o
set auto? false* H7 g, H4 B3 P9 t: M
set green-light-up? true$ K2 O+ M! q$ X7 o. w6 i1 I
set my-row -16 V% C- z( B; z( t
set my-column -1# M, n# d$ | a8 [8 @6 }
set my-phase -19 H# y! N2 L) G
set pcolor brown + 3
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" Q: E' R6 |1 U" _& h" j9 y: u ;; initialize the global variables that hold patch agentsets0 t p! x! V @9 d; \. q7 _: E
set roads patches with
4 M% s/ k' n( g( H9 L [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
5 \, k# h. J- y% g! e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]) q1 C* T' V% G) F; {7 \0 u5 ?
set intersections roads with
, U; h' L, \5 T. k9 b5 d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
6 G6 d( ~1 q; X0 e8 R- [ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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9 k8 O$ @- p7 N/ _2 j ask roads [ set pcolor white ]
! x8 g0 Q+ Z, B: b; D setup-intersections" x1 I+ h- U) |* F) p0 w8 K
end
4 S3 D" U: E' X; y6 }/ Z7 B其中定义道路的句子,如下所示,是什么意思啊?( w2 ] g7 }- k N; R' ]! O
set roads patches with
2 o+ G, w# E0 e A, s. D0 ^, ~8 | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 s! i, Z* L; H' o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" g* M3 @& a2 ?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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