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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。
3 m. }& R: b) W+ |5 f6 v3 knetlogo自带的social science--traffic grid这一例子当中,
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/ O2 |- Y, n+ s& p2 H grid-x-inc ;; the amount of patches in between two roads in the x direction0 E" t+ o# U" T4 t& G* ]
grid-y-inc ;; the amount of patches in between two roads in the y direction S/ Z+ K! C1 p2 L
acceleration ;; the constant that controls how much a car speeds up or slows down by if
, X. D% ^# u m# C1 @+ | ;; it is to accelerate or decelerate1 X' t h6 U" J8 o" I" ^4 N( G; v
phase ;; keeps track of the phase+ I9 {; l9 F2 k( f. z% O2 ]$ r J
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
1 O" R7 b" P$ J7 c! N1 q current-light ;; the currently selected light( C7 {( T9 Z0 e! m+ @* v8 N2 h
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;; patch agentsets
6 N g8 J, @) J# t, E$ e8 Q intersections ;; agentset containing the patches that are intersections
N, [% n' m; A: A# ]: s# f. u4 { roads ;; agentset containing the patches that are roads! X- P1 D7 X4 M. i, X0 p9 q2 @' E
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6 q8 Q6 m8 C2 Q) C7 Hturtles-own: A) K! ^$ I( }( ?4 `7 ~3 D
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: W8 Y* Q. H J* R B speed ;; the speed of the turtle( W# |; J, X+ T/ I% R) f7 F
up-car? ;; true if the turtle moves downwards and false if it moves to the right: z) w$ r$ Z: ~7 d
wait-time ;; the amount of time since the last time a turtle has moved6 O% l4 r) t( t) ^
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
, _( \ E: O/ C green-light-up? ;; true if the green light is above the intersection. otherwise, false.8 E9 W: G: M8 A/ X/ F
;; false for a non-intersection patches.
/ p; a, h3 K, q: k my-row ;; the row of the intersection counting from the upper left corner of the4 ?$ k# O. {/ |1 T
;; world. -1 for non-intersection patches.# o- k* J U( D
my-column ;; the column of the intersection counting from the upper left corner of the) L# a, O$ L( z- j8 K5 A
;; world. -1 for non-intersection patches.2 E% J. _3 l9 S/ m1 u; w
my-phase ;; the phase for the intersection. -1 for non-intersection patches.% Z- m- K5 y' x+ y: W
auto? ;; whether or not this intersection will switch automatically.! w- ?3 E4 [& f5 n
;; false for non-intersection patches.# E& a$ A# |( \( {+ s6 X
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;;;;;;;;;;;;;;;;;;;;;;. q+ o! |8 H2 {5 G0 i6 F
;; Setup Procedures ;;
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- v7 u! Q' E* S;; Initialize the display by giving the global and patch variables initial values.! ]4 M0 y3 c* _2 I2 @1 y
;; Create num-cars of turtles if there are enough road patches for one turtle to) o( a) G1 i" L) E4 v
;; be created per road patch. Set up the plots.
5 P& `5 x. P7 }4 a9 |3 Ato setup
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setup-globals, Q, o8 n& g6 O3 q
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;; First we ask the patches to draw themselves and set up a few variables
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make-current one-of intersections
/ ~& g; v. c: s. S4 W label-current
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; P7 y9 D* m' _* U Q set-default-shape turtles "car"
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if (num-cars > count roads)
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- `& d: x- {, @ user-message (word "There are too many cars for the amount of "
# C' y4 K8 M6 \3 a3 x4 Q "road. Either increase the amount of roads "
, E% t+ [* g6 c "by increasing the GRID-SIZE-X or "! E) h! O" Z* h) |
"GRID-SIZE-Y sliders, or decrease the "
/ M/ k( r M0 d1 Z; _ "number of cars by lowering the NUMBER slider.\n"
. V; ~0 r [. m) e, V/ R& m* K "The setup has stopped.")# T2 i. V0 A3 h# a4 L
stop
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1 F2 V5 g6 w: S& ?1 N1 O ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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setup-cars
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record-data, C2 l! ^7 \) Q. v, v
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;; give the turtles an initial speed
) N1 a3 X0 u' ?) S5 G# R3 ~ ask turtles [ set-car-speed ]/ W$ v0 R5 E2 Z7 `- X- O! W$ A
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reset-ticks
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;; Initialize the global variables to appropriate values+ U# z1 T; [2 ?& j; F* G& R
to setup-globals
9 ~+ q. R2 V7 W% |! Y set current-light nobody ;; just for now, since there are no lights yet
* R; j8 n; L% X set phase 0 B# L/ } p4 L
set num-cars-stopped 0+ b; i ?1 T$ g' b% o/ G/ y" G
set grid-x-inc world-width / grid-size-x
8 P( ]: n# m* p. w0 A* Q set grid-y-inc world-height / grid-size-y1 @5 t5 S) `1 g; N0 E3 I# x& d
& m' v" Z5 H9 d7 P7 j, d ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary/ y1 ^4 G6 ^' p7 I0 ?
set acceleration 0.0993 S# @ c- F2 c' H
end: H7 o9 i& b+ @5 H, n/ x
# f% U: k. J" `5 s6 i;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 w; {( x+ j% ?' P( F* B' }1 j
;; and initialize the traffic lights to one setting; w# j7 E) z, D, ^" ^
to setup-patches0 q. \* M3 b( ~* A0 ^7 o. ^
;; initialize the patch-owned variables and color the patches to a base-color/ J$ S& i. Y @% L% P
ask patches" H% X7 `# S1 p; a
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$ d' n Q+ Y/ h# H' A set intersection? false
) d1 i% ]6 r" T7 l8 D3 ^! e+ [ set auto? false9 `: j) d M2 E/ R- c7 x8 s
set green-light-up? true
* r2 ?( F4 w' a7 x set my-row -1
& q# ]* P9 t( P/ I; ? set my-column -1
6 Z% u, `. X" I; t set my-phase -1
' E- D0 K* \9 F' i6 \/ {, N [ D set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets* D8 |* ?- N0 {& p* A
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 c+ z# J. K+ l0 {: l' _1 [ c9 w
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)] j/ v& h9 q$ @5 }1 \- r* R) }
$ ]6 x$ P* j: L0 J' s0 S* b ask roads [ set pcolor white ]
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0 ]$ @7 m, j& u# \! \其中定义道路的句子,如下所示,是什么意思啊?
$ Q) p4 y. Q( Z# \% T set roads patches with
/ P) a* D1 ?6 P: K( ~: _/ | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 W O+ Z! ^0 } I' Z0 M/ o& ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! i4 h; m/ n- k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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