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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 A/ S/ V6 ]1 o) Y# R5 ?netlogo自带的social science--traffic grid这一例子当中,
Z6 ] T& [, K' {globals
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8 m$ h* k- C j, n: u5 `1 ^# I grid-x-inc ;; the amount of patches in between two roads in the x direction0 J9 w% o- R7 g( F& ]
grid-y-inc ;; the amount of patches in between two roads in the y direction
3 U1 |8 I3 e( O0 \( ~ acceleration ;; the constant that controls how much a car speeds up or slows down by if' f5 Q% G B& f
;; it is to accelerate or decelerate
r3 v2 G( J; l) j; t phase ;; keeps track of the phase
& j5 @3 E% L6 O' h, y. Y num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
+ I- p. x; y# V% @: J% \" r$ X current-light ;; the currently selected light
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1 z: @& O, B4 Q0 e% k ;; patch agentsets
# [" y! X, _. y, Y+ J! u$ j% ?' P% I intersections ;; agentset containing the patches that are intersections6 }, x9 _% W5 \
roads ;; agentset containing the patches that are roads
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turtles-own; S8 E7 @/ u) m/ @' i3 a7 ]1 u
[
5 ]3 n' e7 Y' f" F* @4 u+ w speed ;; the speed of the turtle
0 i% `; p/ N* d up-car? ;; true if the turtle moves downwards and false if it moves to the right
4 d' E6 s( B! A$ x wait-time ;; the amount of time since the last time a turtle has moved
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patches-own. k! ~# U+ Z; d+ l/ N% ]; A/ ?9 H6 {
[! b0 A$ E: n* T6 {( a
intersection? ;; true if the patch is at the intersection of two roads6 x6 V' [4 g. X. w4 u; |7 ^" w
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
+ Z6 K4 @5 b! T# @: n9 L \. f: ? ;; false for a non-intersection patches.( C/ S6 P3 v) d
my-row ;; the row of the intersection counting from the upper left corner of the8 V4 h$ U1 Y' @+ M
;; world. -1 for non-intersection patches./ M7 s) Y: a0 L& Y
my-column ;; the column of the intersection counting from the upper left corner of the. [* ], ^/ p/ H) v4 S
;; world. -1 for non-intersection patches.
2 [- C4 l( F9 `% u- _! ?, i7 s my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 K) @: ~9 U" [" R* h auto? ;; whether or not this intersection will switch automatically.( U5 o: C2 y8 P+ \! i- W( U7 ]
;; false for non-intersection patches.2 D+ h: s' O3 e' n+ W) y5 |! O
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$ g4 ?3 ~& R: `; m* v7 }7 o;;;;;;;;;;;;;;;;;;;;;;
- ^& c6 G7 z8 ~0 W+ ^;; Setup Procedures ;;
! D9 @5 f5 {: ^9 i0 r;;;;;;;;;;;;;;;;;;;;;;6 c3 s6 F! T- [6 a
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;; Initialize the display by giving the global and patch variables initial values.: @$ L+ F+ a: b3 @: C
;; Create num-cars of turtles if there are enough road patches for one turtle to, K* }: d5 s* x+ I& L
;; be created per road patch. Set up the plots.& ]6 m- K8 n/ x. `5 k& F
to setup3 f) s2 \4 M7 ^+ y, e
ca* `8 g' d( s2 _( D; w- O
setup-globals
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;; First we ask the patches to draw themselves and set up a few variables& _1 t+ t; N5 Y) |9 `+ U, m) s
setup-patches5 W2 {( k- Y3 o' P8 j$ n6 U% D: [, c
make-current one-of intersections
' U6 ^( A! B+ ^9 W label-current
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set-default-shape turtles "car"
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' ^" h2 f0 S2 ] if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "7 [0 M$ u9 L5 D, a; B
"road. Either increase the amount of roads "9 Z `/ [2 M6 o% I7 z7 B: Y0 i
"by increasing the GRID-SIZE-X or "6 y1 A+ u# @( U: V6 o7 }' j
"GRID-SIZE-Y sliders, or decrease the "
* g( U$ Y) f$ s, a& g "number of cars by lowering the NUMBER slider.\n"9 M% R/ P2 Y' {- k1 X+ Z7 n. p' q
"The setup has stopped.")7 Y& A8 q4 k% e& i& |6 B# H8 ~
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
1 Q8 l0 h, T/ }. _) t crt num-cars7 D3 N) c1 Z" y/ M8 n/ C
[
6 w# Q5 l+ s8 E" F setup-cars
' I6 A' o2 N; A set-car-color
1 e( M4 X! x, R3 V: }8 ?/ B; F record-data& W4 n; H [/ [- N t1 u
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1 b! I' N2 G- t ;; give the turtles an initial speed
6 ^' j! X4 L3 r ask turtles [ set-car-speed ]
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reset-ticks5 J/ h' X: q6 g0 h' p
end
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3 D7 @( u3 G* ]- @;; Initialize the global variables to appropriate values
# P* J2 L% S3 x1 p8 Zto setup-globals
" J+ Z: l5 F/ [6 t3 Y' x% _/ F set current-light nobody ;; just for now, since there are no lights yet& c( o# a: A$ U+ e2 m9 g$ u
set phase 0
_1 {- c' u( w; j set num-cars-stopped 0
; o5 D- S/ O+ D, ]/ m set grid-x-inc world-width / grid-size-x
" T+ w: g# h, V. i8 q; U# ~ set grid-y-inc world-height / grid-size-y/ v& {3 D: C8 u( K% f; V+ Y' S
0 j4 V, B, I& v( _ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary% ]! R1 t6 _# d
set acceleration 0.099
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" O1 A1 Y' ]6 W0 x* }2 C; b
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
6 V# L) x4 u( \/ ?;; and initialize the traffic lights to one setting; H+ m: U. H& D+ L2 C5 n. T, G
to setup-patches' [0 _- h3 I# W- \
;; initialize the patch-owned variables and color the patches to a base-color1 u/ B% Y, p5 y! Q+ l* J
ask patches0 K8 @4 V. K( n' Z( G
[
4 t3 h6 d& v0 q) g6 E' u set intersection? false
/ P# y3 I, x% \7 \/ V# ?/ A) n set auto? false$ K& f8 b& Q: n: l; V: O$ ]
set green-light-up? true, f5 f6 t6 I7 W9 k0 s
set my-row -10 H! o/ M+ D% T. y. \% @
set my-column -1& h8 k+ j U% o5 ^1 z
set my-phase -1
1 @ @1 t( B8 t( j1 U- P set pcolor brown + 3. a, G2 _9 w" n6 ~; _" D
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8 T1 V8 F/ M: q6 F) V2 l ;; initialize the global variables that hold patch agentsets
s" o: a5 U& _/ ? set roads patches with* N( q- T% k$ \
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' D7 u6 S5 Y7 z+ K _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]) V) K: I+ @: D5 U; y1 X
set intersections roads with
! A8 c# [. o! F; `9 r" R [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
- i% L5 ^/ l: g (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* {% p3 @4 O0 t
0 a/ X6 H0 v) A4 H1 D r ask roads [ set pcolor white ]- N# c/ E0 _0 x# i6 n: i# v
setup-intersections
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) v5 n+ r% P0 F8 f其中定义道路的句子,如下所示,是什么意思啊?
4 S5 N% P" n" l2 W$ i* [3 y set roads patches with1 A0 J# S& b$ q# U$ d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 e! i. {" {* r) D/ y0 j% {
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ {& P7 @4 w$ }' S! X- C% [8 d1 n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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