|
|
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。# v2 O8 _: B$ B
netlogo自带的social science--traffic grid这一例子当中,3 M: v' U0 j/ F/ W" ^7 L ~
globals! E. Q5 ~) d2 B/ C0 \/ ]' J' V
[! }( T4 m8 f+ x
grid-x-inc ;; the amount of patches in between two roads in the x direction: Q6 |& `; v$ N
grid-y-inc ;; the amount of patches in between two roads in the y direction
5 X/ |% J: Q) {3 T% Z" i acceleration ;; the constant that controls how much a car speeds up or slows down by if: N5 }% E6 T$ Z" r% u# {0 D. p
;; it is to accelerate or decelerate
3 m% ~/ ~* U" R w phase ;; keeps track of the phase, ? p% s. n \; J
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
4 g2 g. Q* Q1 v% e7 P current-light ;; the currently selected light
" Z$ y/ a/ d! E' X5 b
2 F2 W1 \6 N5 s' \' l/ F2 l7 Z0 u ;; patch agentsets
1 b" L; L/ d( a intersections ;; agentset containing the patches that are intersections5 r* z2 w8 a1 N" |* m2 Q# p0 X$ b
roads ;; agentset containing the patches that are roads
: g; I3 z' B. X9 a9 `; j, S9 T]0 p6 L/ A$ {& ?8 U/ z/ q- y0 z. Y
5 x" n' z" e5 ?% N: _9 {# ]- ?
turtles-own) p+ V+ k2 }) V
[
. [3 \7 ?$ l0 [7 _ speed ;; the speed of the turtle" Q( ?* S7 C) j4 G7 W' Y! y$ i
up-car? ;; true if the turtle moves downwards and false if it moves to the right, q! S$ C; Q/ m1 h. Q9 l. }
wait-time ;; the amount of time since the last time a turtle has moved
e6 H% l6 M' M! \4 n0 f]7 x! R* b4 f$ v6 L- f: b, f
0 ^7 T8 p- P9 Y; Y& u5 l8 [" fpatches-own: u3 }% K# g$ _* O2 a
[" d' j3 O: L: S. V/ Z
intersection? ;; true if the patch is at the intersection of two roads1 F! p4 h( B( ~4 M. z
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- u( Z( }8 _. h ;; false for a non-intersection patches.
' N3 n5 W$ D) U2 V% q# M my-row ;; the row of the intersection counting from the upper left corner of the2 p% I' Y9 d @9 R
;; world. -1 for non-intersection patches.& h7 e7 u. `4 o: u: L1 f& u
my-column ;; the column of the intersection counting from the upper left corner of the
/ w5 k6 a, J' G4 c/ J ;; world. -1 for non-intersection patches.
2 {& T: r, F! v5 h; N; T, t my-phase ;; the phase for the intersection. -1 for non-intersection patches.) ~1 x4 P2 o: ?8 M; n/ F# Y- n5 Y7 S
auto? ;; whether or not this intersection will switch automatically.
2 {' h5 e2 Q' ^1 { ;; false for non-intersection patches.
/ f* |( L) ]( P/ p]
& x) S/ D$ o4 t ] a* w. P' b1 _) ]" K+ |4 T
- a- ?" c: `4 B7 k) S! W; r* i# Y;;;;;;;;;;;;;;;;;;;;;;
0 p; H; \7 j2 e# A W& v4 m;; Setup Procedures ;;& G7 f& ~" l% }# ^2 S4 K! b- R
;;;;;;;;;;;;;;;;;;;;;;* ]9 Q% V0 P d: m% H
4 I; ]4 \7 }. p% ~% b/ Y8 I;; Initialize the display by giving the global and patch variables initial values. I7 d, ], Y5 n' _
;; Create num-cars of turtles if there are enough road patches for one turtle to
3 V. Q7 r$ d) c/ e$ E* _% l6 {, R8 e6 [;; be created per road patch. Set up the plots.
; z2 |- R5 r; v4 \9 c0 X' k. d; [* S8 Tto setup
) _0 s* ]: R4 s2 ?# c ca
* Y5 P; w# S' Z0 W) i setup-globals
6 Q) T" n# w4 o" d$ s0 S8 U' t. q; j I' S) c5 I% k4 o
;; First we ask the patches to draw themselves and set up a few variables& W8 d. R" y% l( y7 o9 R
setup-patches
# U# r2 y4 M0 G make-current one-of intersections
+ N5 d/ ^/ ?2 E3 V4 d$ T/ I label-current* S% R6 _; a8 D1 p* `- S9 b3 j
; d. X; ?" J, c6 h T) A set-default-shape turtles "car"8 U: P/ ]1 h- _8 G( Z: M
/ q" O5 x: j6 K7 H8 r; _' P+ a
if (num-cars > count roads)+ `! F- I6 Y2 F
[
: K& }+ W1 i5 ]- Z. O user-message (word "There are too many cars for the amount of "
. f) W8 C, p0 V" o' K "road. Either increase the amount of roads "
. h2 h& |6 c3 @* g "by increasing the GRID-SIZE-X or "# r0 l* f3 t3 i+ |" n& I
"GRID-SIZE-Y sliders, or decrease the "
! ?9 g+ y7 G1 n7 ~7 S: w# Z1 C "number of cars by lowering the NUMBER slider.\n"# O2 `# [2 f' v: t( r: T
"The setup has stopped.")
- \$ S* ?2 } x4 \ stop+ m" \/ M0 K" H6 ^# A6 K
]
8 R. W) ~* d! Y0 R z a! d
6 ^. u) X$ b2 g! C+ g) I8 Q ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color; B' k E, j, q/ V
crt num-cars" h& A+ W1 j) p8 P- K& U5 g5 s
[% C. D! j% Z4 P2 f# ]8 ~1 }
setup-cars% V* q+ u+ G- l8 L
set-car-color
1 ` m$ \) e7 I record-data
) B! d1 M- x0 _1 F4 E ]
' _/ o# E( A2 d: D, G/ _3 c4 k8 x T2 O8 F2 i$ E: [6 G
;; give the turtles an initial speed
2 m# x8 @& Y: N. @& B/ A5 f% i2 l4 Z ask turtles [ set-car-speed ]
/ ~) `9 a+ E2 J6 U
: Q9 W, ^ G; z# c+ w reset-ticks- ~* X' p% B9 l) x
end2 @9 w+ D. m; n/ ~5 ~: O f
# u3 [+ v& U u' X;; Initialize the global variables to appropriate values# r5 i/ @7 `: ?# U# V
to setup-globals h+ N6 d# ^0 v/ O# ~% Z
set current-light nobody ;; just for now, since there are no lights yet
4 U1 P$ t! i! S4 u; k set phase 03 L: P: K7 X; j5 }/ I" b: ~
set num-cars-stopped 09 P, u& w0 T7 N- S( I
set grid-x-inc world-width / grid-size-x
# m. t9 s0 Z2 h' a$ U set grid-y-inc world-height / grid-size-y
) H. @ x% }$ Z% ]; F% N4 ^. T l
! r. b8 Z* P* H/ m ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary! c; @# e) u( n0 |- r; f0 y
set acceleration 0.099; R' J' T* r! P- U g& S
end
9 H1 p! z. V/ A0 b4 w. O M0 B; j1 O! a& B
;; Make the patches have appropriate colors, set up the roads and intersections agentsets, x! u/ @! ]( F3 i" ^3 W
;; and initialize the traffic lights to one setting
4 [6 T4 [3 W8 B. g- I+ K; Uto setup-patches7 F' \5 q( Q! D- S) G% h
;; initialize the patch-owned variables and color the patches to a base-color5 o/ A2 t/ G& C9 k/ i. s
ask patches
9 e& \' X& P7 ^! |0 q: t [
/ `% }7 u' }% z3 X( N% h set intersection? false, g9 R; f1 e6 W! q! t: Q7 ~* B
set auto? false
8 } C3 k4 m7 F set green-light-up? true
9 `1 {0 ~+ d. G1 Q; ^ set my-row -1
6 T; q5 E0 q5 y2 ?* }: t' R# @) ^& o set my-column -1
+ }6 Y1 u$ f% I- \5 j s set my-phase -1
/ }% a9 B" [. e set pcolor brown + 3& Y/ p6 m( _8 t f
]% Q+ d) t. p* z
$ W. l4 ~# x" S$ J$ z4 H& p) x0 B' H ;; initialize the global variables that hold patch agentsets. S" W& r! k. g; g# ?
set roads patches with- i3 n' X0 h- _" X' y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
! q8 {8 X2 e; b/ c) K/ w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 l7 W" ~: A. w5 y* h2 Q. o
set intersections roads with$ d1 [0 ^/ U- e+ X
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
5 L9 z/ E1 C$ n4 i3 O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- v1 x7 X- v: V! A' R) V
% W8 [0 \0 f' g6 L& A- g K ask roads [ set pcolor white ]. i! R8 f8 ^# r+ y
setup-intersections8 } O' u. S, P& q+ i: s7 O1 ]
end# `3 s6 P5 D- [
其中定义道路的句子,如下所示,是什么意思啊?
2 t. J8 X! }: D& m4 ~. {5 d, \ set roads patches with# |8 }( [$ g6 e& e7 ?
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 E5 [* l; ~1 S! }. u8 r, A
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ {1 x: E; D8 O1 T( H7 }
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? |
|