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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。# l" G5 u* ?* ]; }+ ]$ R
netlogo自带的social science--traffic grid这一例子当中,& Y5 |( W7 f# ~" i8 F8 `
globals! E, l! @* D/ b D5 J
[
6 P/ B# q* m8 Q5 m grid-x-inc ;; the amount of patches in between two roads in the x direction1 D9 q; [! `/ m& ^! a5 d, d) x
grid-y-inc ;; the amount of patches in between two roads in the y direction4 ]& g" g) Q; i0 P$ K
acceleration ;; the constant that controls how much a car speeds up or slows down by if
6 h$ ?, A* A& M' [1 L" M f ;; it is to accelerate or decelerate
8 v* E7 j( V; Q& \0 O phase ;; keeps track of the phase
9 x t) E$ o% c$ C num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure* t8 T6 {" L1 t$ `" p
current-light ;; the currently selected light* P2 L! Z; \- ] Q
8 H7 q+ N! V; Q ;; patch agentsets Q3 m. O d9 J# I$ {
intersections ;; agentset containing the patches that are intersections) P$ u- }/ X* a" E0 f0 ]
roads ;; agentset containing the patches that are roads* n6 I1 O o. k2 q0 ]; b" E, B
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turtles-own8 u7 C1 a4 J0 J
[, \0 T3 a, B3 z/ I. `+ Q
speed ;; the speed of the turtle! x" v, q+ R8 R9 q" I$ f
up-car? ;; true if the turtle moves downwards and false if it moves to the right/ }) ]- B5 n' `" M: O( ~3 v
wait-time ;; the amount of time since the last time a turtle has moved8 j6 R: y% H1 n* G
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) L' t+ B" r; k6 A3 l& t* {patches-own. f: N. x; a0 z8 J5 t+ _
[
' C& x2 Y# J4 i% J) P6 X intersection? ;; true if the patch is at the intersection of two roads
" M3 p9 E# ~, l5 u2 y2 H) g green-light-up? ;; true if the green light is above the intersection. otherwise, false.
' y. v, N& J' G; j: { ;; false for a non-intersection patches.; s1 C3 ]0 y. i, v# B
my-row ;; the row of the intersection counting from the upper left corner of the
, a \% }! v5 U* Y, Y6 n/ `* h ;; world. -1 for non-intersection patches." B0 y% O" U/ g6 B; Z E' ^( r
my-column ;; the column of the intersection counting from the upper left corner of the
( W. e$ G/ d5 B* M/ |2 D: \# y ;; world. -1 for non-intersection patches.! q# a8 Y. x- J6 n
my-phase ;; the phase for the intersection. -1 for non-intersection patches.; Z) g+ M" ~8 l' a
auto? ;; whether or not this intersection will switch automatically.( H. e$ K5 \$ M0 v0 K' R: y* ~
;; false for non-intersection patches.. g7 }: P, s* B* S' o
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. F6 r- G2 P8 t2 ?# f;;;;;;;;;;;;;;;;;;;;;;+ F, f& ]/ f1 E( G* W1 Q9 c) g
;; Setup Procedures ;;
( f$ @8 `# F4 j# C7 V2 f;;;;;;;;;;;;;;;;;;;;;;
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5 V, e( _+ {( J1 i;; Initialize the display by giving the global and patch variables initial values.
, b4 f0 V( J5 ]3 b& h1 w8 V;; Create num-cars of turtles if there are enough road patches for one turtle to# @0 |' E& H& n4 _) {" K- a
;; be created per road patch. Set up the plots.0 j' [: g% U6 O% x: ]9 X- \
to setup8 {. t+ {. x6 F- |& [
ca+ {0 K/ Q( E% R* ], @ S) p
setup-globals. P9 D5 X6 x" Z6 y- {
) P/ X8 A8 I, `) Y7 T, C4 z9 t ;; First we ask the patches to draw themselves and set up a few variables
/ Y7 K" R' x' R# \4 I! c- ?1 T setup-patches
& H) l9 p9 a( s7 T" ]* A3 @ make-current one-of intersections' A! C% c' m. m; }1 o1 A4 g8 S
label-current
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8 Z2 R$ }1 [3 s. \. `3 V3 h+ n set-default-shape turtles "car"
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, m0 a: f% B5 b1 g if (num-cars > count roads)1 Z5 T- G- G/ r" W$ W
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user-message (word "There are too many cars for the amount of "
8 P. ] Q) F4 f: Y9 G5 C' b9 u# \0 a "road. Either increase the amount of roads "3 G5 ^5 g3 z, M ]0 P/ c! q
"by increasing the GRID-SIZE-X or "
% R9 p8 X3 S3 K. s+ ~$ I1 t "GRID-SIZE-Y sliders, or decrease the "
1 D! [6 W- }5 _# j6 A: B/ H6 ]6 k$ j "number of cars by lowering the NUMBER slider.\n"
- s$ U, r3 `8 v' D) ?4 v "The setup has stopped.")! D! R9 v/ w' _# L' f& h
stop& A! a3 H; E& U+ d
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0 |( T3 i! |' G: a) c! r4 k ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 F1 z( Y, h' f/ V( ?5 O5 _. H& R crt num-cars" ~& q8 I( Z& c( _
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6 i( Q+ E: C. n% ? setup-cars+ l) Q& e' a" D; A
set-car-color* q2 I1 [! l, Z$ C
record-data& `( k# D; Q) e2 X: i
]
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9 P* Z: p6 I4 f6 @ ;; give the turtles an initial speed4 r7 }- [2 n% j
ask turtles [ set-car-speed ]
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reset-ticks
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{$ y* w4 r3 x$ d" f2 `;; Initialize the global variables to appropriate values7 r% i- ?- H" `' B
to setup-globals6 L9 \ w0 h- N( @5 i
set current-light nobody ;; just for now, since there are no lights yet
6 x: S# P8 A0 ~/ F set phase 05 }1 i* l' [1 m* g* H( j
set num-cars-stopped 0# S- {) x( w% ?, L4 s
set grid-x-inc world-width / grid-size-x& ]: t+ z0 X7 o }! M( M
set grid-y-inc world-height / grid-size-y
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5 j8 R2 K% D! H& E0 q, |' I ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
z3 U+ H' g7 ?# X3 v- ]8 C" f set acceleration 0.099
( R9 y0 k. m" t* n& q6 [end. d$ o1 w9 ]" J0 b: |
* j: @: q- B7 h. ~5 {9 i
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,% o: D# n' y9 v6 A; @9 p
;; and initialize the traffic lights to one setting5 P4 q- P6 L" \7 N. C# t! G( F8 o
to setup-patches* C5 C5 C& @3 L2 ^' u3 ^
;; initialize the patch-owned variables and color the patches to a base-color4 c6 ^, Y0 M7 P1 Z1 t! S2 W
ask patches' I7 T( f( V- c, e7 [ o% F
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1 {- T- L( |" x2 V+ X% Y! S set intersection? false
P2 [ ]6 M3 n" I/ p2 f set auto? false
; Z( k+ r0 G5 T8 x7 e" t6 w set green-light-up? true
" I' J5 e3 r* H4 `. q4 z# T! ^ set my-row -1$ o! W4 u9 U+ |; b
set my-column -1
- B. j3 d/ W0 k set my-phase -1. |7 P) R/ L& }$ g7 z
set pcolor brown + 3; q% r: E( F4 {8 h6 q1 X
]
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;; initialize the global variables that hold patch agentsets! L. _, T. Z" D; Y# X' p
set roads patches with
0 ^7 h1 Q! V- r' ~$ S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: K& {: g3 h& d$ _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
r6 H1 S2 D: X* X" {8 | set intersections roads with: P! ~/ g4 B+ ?$ p2 U
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and; d7 C5 v2 Z9 D2 m
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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: U1 e( H0 c9 J2 }) a: f( J ask roads [ set pcolor white ]) i: Z& `8 r% B/ M$ E% e
setup-intersections4 c7 k _. A) B
end
: E' ? }4 a, i5 H其中定义道路的句子,如下所示,是什么意思啊?
2 f4 `7 f. j& G V1 T' i; f set roads patches with2 n5 w: C5 K. D
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ k1 S- W: H, z! C9 |0 L7 N$ J
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]: d7 [& q4 M1 I7 z6 t/ H8 F3 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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