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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 D1 K7 W2 Z0 R- r& ~netlogo自带的social science--traffic grid这一例子当中,
: @9 o7 |: |& q; l1 `globals( E5 h5 _4 D! L* p
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grid-x-inc ;; the amount of patches in between two roads in the x direction
H2 N5 H/ d. J grid-y-inc ;; the amount of patches in between two roads in the y direction9 L2 j9 v: |: l' x- H) N P2 F
acceleration ;; the constant that controls how much a car speeds up or slows down by if
; ], c# z. t5 N0 q; u/ G ;; it is to accelerate or decelerate
) f; ?. O% y1 U! u# R, C phase ;; keeps track of the phase1 r" } |0 |) G+ Z+ y \2 f; {
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ _! a9 d2 m# T( ~6 ?
current-light ;; the currently selected light
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;; patch agentsets
9 U0 I7 M6 X3 ^; K4 j' k2 V5 O intersections ;; agentset containing the patches that are intersections
! ~# S5 @& _6 I7 {6 ^ roads ;; agentset containing the patches that are roads+ F1 \1 r1 ]( s! e. G5 h- j
]
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' H; M5 W2 J8 k! s6 f& v3 W F$ lturtles-own! ?1 `( R5 H! n. l0 H4 r2 G
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speed ;; the speed of the turtle
5 H. }. l D# i& i up-car? ;; true if the turtle moves downwards and false if it moves to the right# O# M1 w4 E, e9 D
wait-time ;; the amount of time since the last time a turtle has moved0 `. I* P0 b# {9 I, ]5 y
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# c9 i, L: \) Gpatches-own
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intersection? ;; true if the patch is at the intersection of two roads* x1 D. N9 P- H& j
green-light-up? ;; true if the green light is above the intersection. otherwise, false.& x* H1 S/ M) r* B/ W) Q
;; false for a non-intersection patches.
q# `- N7 u( B- E2 f my-row ;; the row of the intersection counting from the upper left corner of the! D9 l6 b) ]( W" N
;; world. -1 for non-intersection patches.) r8 X: B2 Y; G% @- x2 Y r+ `, e
my-column ;; the column of the intersection counting from the upper left corner of the
( y8 T4 q; ?% t% q% q ;; world. -1 for non-intersection patches.
2 y4 h+ J% o U% R' }+ I e my-phase ;; the phase for the intersection. -1 for non-intersection patches.+ r4 h3 y! u9 T1 F9 }6 D4 V8 m
auto? ;; whether or not this intersection will switch automatically./ ^/ Z; u1 `# J v
;; false for non-intersection patches.+ h1 f. n( C% b# y# S+ [. u, C) o! q
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6 T! W9 _1 {$ A0 s: [7 ];;;;;;;;;;;;;;;;;;;;;;
7 Z! o$ s/ y% s" l;; Setup Procedures ;;5 A% T% Q, O' g
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
( i( Z; C: s# {# F& V;; Create num-cars of turtles if there are enough road patches for one turtle to
0 x+ t' o% P7 K4 f+ b) V4 o |& A+ t;; be created per road patch. Set up the plots.
% a; y3 ^2 L" N# H* yto setup
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" } j9 l) j- A0 g& s% z, z setup-globals) w! [4 y$ S" R# f
2 Y" F+ b" A, p ;; First we ask the patches to draw themselves and set up a few variables( ]6 D( ~3 W5 {
setup-patches
" o+ o/ f; x+ h) r make-current one-of intersections
- j- s R" t2 p( C& F ~ label-current/ e& M7 z4 R( v N& D/ m
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set-default-shape turtles "car"
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if (num-cars > count roads)
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$ o; b* v- } A9 X user-message (word "There are too many cars for the amount of " @# f9 b9 F6 b) U( k- K
"road. Either increase the amount of roads "
& [; w7 e3 s0 {; J6 K "by increasing the GRID-SIZE-X or " {, P/ W2 V& z# _' M
"GRID-SIZE-Y sliders, or decrease the "
% P" n& o- _' A "number of cars by lowering the NUMBER slider.\n"
2 q' m7 ~5 t0 v, i$ r "The setup has stopped.")5 g- N- ]9 K9 Q7 e0 X+ _5 o3 A2 t f. q
stop
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! V7 e7 ^9 ~" q+ l, A% U ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
: m. l3 z! }- p u T! v# N crt num-cars/ d2 t) p# c; w$ a, y; z! ~
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setup-cars
7 p0 Y5 e4 q7 l' A! A: Y$ B0 T9 G set-car-color! q, q. x" D- F
record-data# r: o Q# a: y, ~+ R" q4 ?8 ~
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4 [) \/ H0 H4 X* H3 t8 o; { ;; give the turtles an initial speed
- s y+ R2 l! h1 o3 E" e ask turtles [ set-car-speed ]
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. p2 q7 q/ t$ Y, V4 e' t+ k9 D: m, m, Y reset-ticks' \6 M3 \5 v( [% f ]
end
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6 i. {. f0 j) X5 |;; Initialize the global variables to appropriate values2 Q: r- w9 D" N$ p
to setup-globals
9 g0 X3 X9 S& d9 L: J r( l) Y0 N set current-light nobody ;; just for now, since there are no lights yet- i' k7 o( l$ j5 K. j
set phase 0
# z \5 ]- n$ K- h; \ set num-cars-stopped 0* T0 I. x5 {+ A2 U& U- C7 ?. R+ L& i
set grid-x-inc world-width / grid-size-x& l& i8 Z3 o( t# I! i( w. E" ^
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$ |* v4 }0 Q# M) @1 S
set acceleration 0.099$ d1 G- e% |7 f a) U8 Z2 y! e
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
! C0 {* H4 L' ^* G' q+ g+ k. b;; and initialize the traffic lights to one setting0 D7 V* f7 f- }2 M/ B3 W6 J: _
to setup-patches
9 H: l4 E+ m( X. c6 v ;; initialize the patch-owned variables and color the patches to a base-color
, p1 P6 E A8 s. Y ask patches
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set intersection? false7 G. d6 `1 N( T* g) R) ]* q
set auto? false
& D- \. v/ L. { set green-light-up? true6 ^$ W0 _& D# r- j) N
set my-row -10 r" I6 x* E( A
set my-column -1
2 {8 P+ R, |) _ set my-phase -1
, q ]! `) t3 f% D set pcolor brown + 3
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& C5 L4 i' F" G# B! ] ;; initialize the global variables that hold patch agentsets
2 v& ~8 T3 Z: w- O l7 P" W set roads patches with
) u3 @& b) t7 w& J& M8 S: U* Y) y [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ v) i! M% ?3 m (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 e6 e- o6 d) }' |8 i# q set intersections roads with( m" {5 S1 {$ U* v6 Y2 p; y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
# ~, e; Y* u8 {& y7 L J (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]9 m# |$ r; }% X
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
) u" M. `) l/ Y% X; E& f set roads patches with
- ~' v1 V/ }! @, N3 X1 f [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- F& J' b5 X0 V (floor((pycor + max-pycor) mod grid-y-inc) = 0)] ?2 j5 w. q# H3 \- L
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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