|
|
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。
2 I: `6 H* ~1 F7 G: unetlogo自带的social science--traffic grid这一例子当中,
2 l# ^: E- {: W5 d a3 N- Cglobals
1 W& h- [8 d) `8 G[
1 n {4 o5 \! e grid-x-inc ;; the amount of patches in between two roads in the x direction) e' s1 y3 ?$ r# y; T
grid-y-inc ;; the amount of patches in between two roads in the y direction
5 ^5 i* p7 C7 d3 x- x S acceleration ;; the constant that controls how much a car speeds up or slows down by if9 U) M6 V4 M; _8 W
;; it is to accelerate or decelerate$ j7 X, J, m2 L, Z, U
phase ;; keeps track of the phase' G: o( d7 P6 N- Z* F' ~9 z
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure/ w. J% L, {1 d ~
current-light ;; the currently selected light2 r! h+ p' y& Y& f# q" y% j
( |9 O. ^$ k% ?# o0 a8 k# T( m ;; patch agentsets3 P5 s4 f# t, x1 c* \
intersections ;; agentset containing the patches that are intersections% K3 @9 `2 g% e, V" B0 ^) e
roads ;; agentset containing the patches that are roads3 C# F4 F- {( l+ A5 _
]
: ^% q* q, X3 E4 N4 h$ X$ m6 a/ W8 A+ m5 i4 K. W
turtles-own
7 a2 ~- c2 p0 j$ C0 L. p[
( R( M7 M. S" c, C2 i speed ;; the speed of the turtle9 J/ |' w) x4 G# t3 C
up-car? ;; true if the turtle moves downwards and false if it moves to the right" d- k0 x: X5 I7 ?4 l
wait-time ;; the amount of time since the last time a turtle has moved' L& t( Q4 O4 t$ X0 d
]
* D' F9 ]# |0 _3 y' T' a) B6 |" i8 k. J9 @/ ~, C8 Z6 o& _% q) B; s& X' A
patches-own+ l9 M& n7 C5 b7 D. p
[/ S q3 L( R- k: B( a2 u
intersection? ;; true if the patch is at the intersection of two roads: s4 {3 P5 _8 N/ u
green-light-up? ;; true if the green light is above the intersection. otherwise, false.: T9 R. h; s" M: X# ^7 ]+ d1 v
;; false for a non-intersection patches.
% T) L. n$ [' H. v2 B0 D4 u my-row ;; the row of the intersection counting from the upper left corner of the% G$ E d, e/ u' S/ d8 Z
;; world. -1 for non-intersection patches.# v3 L) I# P$ P7 I- D
my-column ;; the column of the intersection counting from the upper left corner of the
0 k8 P9 }. C L ;; world. -1 for non-intersection patches.
6 ]9 N, a. P& M( x/ M my-phase ;; the phase for the intersection. -1 for non-intersection patches.8 C& b( T/ L( W6 ]
auto? ;; whether or not this intersection will switch automatically.
+ _, r; {" J. j) ~- t! X c ;; false for non-intersection patches.2 A5 Z; B6 Z% V0 T3 @
]$ v. V3 A* @7 b j/ J
6 W( A* S8 ?1 e* E% v `9 \# {& G" y) L- P: s* L0 H& A% @
;;;;;;;;;;;;;;;;;;;;;;
. u& t2 U& D) n) @;; Setup Procedures ;; U, g# p9 {& `8 Z0 l2 d: I' Q
;;;;;;;;;;;;;;;;;;;;;;
2 P9 F1 X, j! d! Y% m) c' H( A/ ?! \% E& Q
;; Initialize the display by giving the global and patch variables initial values.& w* E: h8 |/ B- r' s9 J' q
;; Create num-cars of turtles if there are enough road patches for one turtle to
7 a( f+ s* n" q! n7 d7 F$ N;; be created per road patch. Set up the plots.* { W5 G8 p' J* Z9 h
to setup
# k4 q8 p, Y! p6 N* X) |# v: M ca
Z* t9 l$ Q; t- ` setup-globals
# h1 ?% v" L# l+ A3 a$ d- \+ v+ R% j. i; D# c
;; First we ask the patches to draw themselves and set up a few variables# P( ]* V2 W3 f8 y( `+ Q! _
setup-patches& J; J" V+ n/ l2 Q" B% n% i W
make-current one-of intersections) D- R+ x) S/ |. M1 K' Q' Q$ ]
label-current8 j% H/ S# F, j0 V
! F/ R4 V* p7 a, h, o' I set-default-shape turtles "car"$ o9 @9 X7 C- F6 K4 w+ K7 B
3 V7 f5 k# k9 _9 B z, v# [( W
if (num-cars > count roads)
+ g% u6 Z+ S- D [* S" |4 U1 N! m, o$ e4 h3 \; C
user-message (word "There are too many cars for the amount of "$ @& S6 o# v# }
"road. Either increase the amount of roads "
# F f4 N3 d! [/ D# n/ y$ ^ "by increasing the GRID-SIZE-X or "0 W% N# Y4 z8 a2 E
"GRID-SIZE-Y sliders, or decrease the "
) h' r" n( ?( K7 X+ \6 m "number of cars by lowering the NUMBER slider.\n"
, i6 ^" |6 {4 n7 p, ? "The setup has stopped.")+ R, K3 h4 ~$ u: r
stop; p; Q3 z8 W: B; o$ g( H/ `
]
; x, Y, e. T- O1 H$ K2 R! Q% i$ i2 \) ]! `$ u2 z: t2 R2 P: e
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color4 W+ ~2 Q; N: J8 @+ ?
crt num-cars; q/ }) Q4 @: r5 d
[
2 @: z' R7 Y" }$ K" d% o9 \ setup-cars. _9 }+ J" l' i! Y; S4 r1 p2 c
set-car-color5 ^, H, Q$ j6 _$ F# l
record-data8 C/ V# I. G m# B! I
]0 a" ]2 G0 N g# K' X
) R2 E6 }+ ^ u* q! j! @8 z+ k
;; give the turtles an initial speed5 M7 H$ J3 S) _0 u
ask turtles [ set-car-speed ]
9 @9 A# x* c1 w! z; ^4 w0 O$ _6 \5 q" A+ g; G' G" z0 o
reset-ticks f2 t4 c9 q' Y8 I2 a' j* c9 j
end
j' E) u; `3 o6 r% M$ ^1 A: o: f' @( U9 [! z; {& s
;; Initialize the global variables to appropriate values
1 I) f* l- H9 t9 ]+ dto setup-globals
+ ~- c# j6 ^" N! q set current-light nobody ;; just for now, since there are no lights yet
$ D: _: v- x( j% n; a- o set phase 0- r$ I' Q# T! f% F/ q W
set num-cars-stopped 0
" O; w s! Q1 g5 ?$ m9 S set grid-x-inc world-width / grid-size-x U. L4 D: m4 ?3 u8 {) j% u
set grid-y-inc world-height / grid-size-y1 L/ H3 m& ?7 K/ R- T2 u7 W0 n+ m
( [% S5 ?3 ^3 T$ r& s: s0 n8 N
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
7 h8 W# x' n0 i7 t" h: r9 f( f8 N set acceleration 0.099
* I3 l6 t% _9 N+ t0 x$ [end
* d3 y2 _6 M+ J( S, _( g. U1 h, L
+ J' t3 {7 j" \2 D' E. O$ A0 v;; Make the patches have appropriate colors, set up the roads and intersections agentsets,1 X) S7 p" l! Y5 p6 o7 u
;; and initialize the traffic lights to one setting
; W3 r, [3 ?7 Z% ~. Q8 qto setup-patches2 ~# O# O3 f5 r6 \/ I2 D; N
;; initialize the patch-owned variables and color the patches to a base-color
, k8 `( B3 V7 A1 {, { ask patches" A* U1 ~5 ~3 Y
[: e0 a6 I" g E" j* {7 B
set intersection? false; A x3 p" j. ?! `! r
set auto? false; l4 m' f/ H/ l
set green-light-up? true
2 `& q1 j3 u" G' D$ [* n. L set my-row -1
" N$ t' _. S _ set my-column -10 {7 u. G3 S+ y$ h
set my-phase -1
" V' s/ M2 U% }: V" x set pcolor brown + 35 x0 A6 F/ X7 r6 z8 [ N
]
. _8 y+ q S" d! I; B
" i' ~, V" M9 Z" @3 v9 P ;; initialize the global variables that hold patch agentsets
' w- A: U8 k9 o3 v set roads patches with
0 I( T- W- ?8 O, N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; v* w$ U" v& Z' H, I0 v5 }: M
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. K7 p7 @: ^ f) m. I Q3 n2 P! p* z set intersections roads with
5 L: I% ~2 h O1 Z! h [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, q" Z7 u: }: V& X: H0 |3 Z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 R, T* u) s& ^9 I: Y
; c' g" n; b3 R ~! q+ L! D0 I4 H ask roads [ set pcolor white ]
% Z& g, i) Y0 \9 |- B3 U setup-intersections
4 H1 j! u' p: }6 G0 Y) fend5 X. s% h( W- h3 ~4 [8 l
其中定义道路的句子,如下所示,是什么意思啊?
. A1 V' c2 h( }& x- D& ^ set roads patches with
0 O9 z: U- F: m; ?8 v* x. X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- Z* c. ^4 G! a1 d5 J# I (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" V! Y' d3 n0 d/ f% R7 ~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? |
|