|
|
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。- c$ ?% F6 e/ C
netlogo自带的social science--traffic grid这一例子当中,
: Y# D* T+ k$ Qglobals
; @1 f" J) I/ c1 A6 N9 ?4 ^[
5 T3 Q5 S* w E grid-x-inc ;; the amount of patches in between two roads in the x direction2 J$ j: V M7 o
grid-y-inc ;; the amount of patches in between two roads in the y direction
' a0 B' l( W2 g$ I4 _/ d acceleration ;; the constant that controls how much a car speeds up or slows down by if1 P' B f: w) V7 F2 ` L5 c
;; it is to accelerate or decelerate
$ u/ _9 I9 W7 I phase ;; keeps track of the phase& I. D' f* V: m
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
0 i* {; y" v9 x current-light ;; the currently selected light
4 B- u: i ?$ K8 j$ ~
' B4 h `- ?* f- f ;; patch agentsets
* n% ]9 j/ ?4 N/ r* j intersections ;; agentset containing the patches that are intersections" O* d X4 P m' \ Z$ B" k
roads ;; agentset containing the patches that are roads
; i7 v) w5 W: ]* ?]
- m$ }" Y# Z$ [$ M
* p" A. P; \0 e, Cturtles-own% {/ E* I) s: H8 \- a
[
& W0 p8 H3 J) t. T3 z/ ` speed ;; the speed of the turtle |3 O* C5 m6 B. O9 e
up-car? ;; true if the turtle moves downwards and false if it moves to the right, f& e( k, L; t$ p: u( W) K8 u
wait-time ;; the amount of time since the last time a turtle has moved5 C# a @; J7 ^/ o+ _! L4 r
]
# ^: V, n& i Y5 d5 Q* J) s3 ~
0 Q4 M+ p2 S9 q6 q( dpatches-own
- R8 P) D' `4 N; e( \6 ]% H* h[* }3 y4 L8 A; ]8 l
intersection? ;; true if the patch is at the intersection of two roads
' K& r% j" m8 [* D green-light-up? ;; true if the green light is above the intersection. otherwise, false.
+ d& X( C4 Z" \2 ?/ X( f: W0 D) A- ` ;; false for a non-intersection patches./ B; E9 J+ Y7 G* R
my-row ;; the row of the intersection counting from the upper left corner of the: {; S3 P& Z$ E
;; world. -1 for non-intersection patches./ ^6 O( q3 T7 q
my-column ;; the column of the intersection counting from the upper left corner of the
# ` d* T+ h) Z) l K# i0 P ;; world. -1 for non-intersection patches.
9 k, n; ^; }+ n/ ~: J0 w* H- t my-phase ;; the phase for the intersection. -1 for non-intersection patches.
" q6 G5 C- u3 A2 z! t( A auto? ;; whether or not this intersection will switch automatically.4 J" |( v6 }* s) j$ w% A
;; false for non-intersection patches.
% v: m3 ?4 X& x1 A3 k& f, S2 E) G]
1 s {2 X# N+ {" n: E' Z' [# m) P& D0 j: ^
* O# a6 z5 [ R% q; j/ I
;;;;;;;;;;;;;;;;;;;;;;
* ^6 p9 u1 W s% P$ `% J# G6 o6 Y;; Setup Procedures ;;
& j4 t; B4 a& u% m;;;;;;;;;;;;;;;;;;;;;;( y! P( p% ^) f) `& F- d5 ?, l, e; k5 {
7 I5 K7 R% O% {;; Initialize the display by giving the global and patch variables initial values.
! ^6 w: _" S# h# ^8 w# ?;; Create num-cars of turtles if there are enough road patches for one turtle to: d9 O. `: l- M$ o& C7 ^5 T
;; be created per road patch. Set up the plots." F% H. A+ V# o- e' m' w$ Q9 W
to setup5 h3 }% c1 t5 n
ca
" W/ \. n& e8 ^4 E. w% | setup-globals
# ~9 Z- l! U! T- R. p2 T9 J! W Q. }! W7 ]/ k+ N1 M% `
;; First we ask the patches to draw themselves and set up a few variables
9 Z1 z; b) f2 A- w3 P setup-patches* |- ` o/ j5 {. M& }- D; s
make-current one-of intersections& ?6 b, f* _6 H
label-current
: I R2 I# ^/ K3 }7 \2 _, x, P( ~4 A, p
* a3 z8 [% d2 V. }7 o1 ~ set-default-shape turtles "car"
0 S7 u- z. ^8 g: k, [" N4 w$ [1 x- E! c
if (num-cars > count roads)& s ^0 `' c! r' S" h+ a: A
[7 P8 d* d7 r# y$ \+ U/ ^0 s" Z
user-message (word "There are too many cars for the amount of "
* { {" ]$ K5 _0 b "road. Either increase the amount of roads "
3 G8 S5 I' r- A+ T) K/ W1 Z( ?* F& F+ A "by increasing the GRID-SIZE-X or "1 f8 A2 a( d* i5 r5 Q1 w+ o2 \
"GRID-SIZE-Y sliders, or decrease the "
8 i& K- t0 T) t3 r. I "number of cars by lowering the NUMBER slider.\n"
2 ^9 L0 @4 D0 P$ G X: g; S "The setup has stopped.")1 l( e+ _) c1 [
stop
& m+ I0 ~/ i- E' E8 B0 ]5 X7 F ]
' ~! e2 K6 r% j7 a, n+ } g2 v6 @, \# `' E1 w# o ]0 ?& u
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color. W- `" ]5 }1 K1 O
crt num-cars% c; r% ?# F+ U+ [
[9 \$ M. L. G. g3 \' T- C
setup-cars
3 [" L% H/ ?' ~( w' E set-car-color0 b# |* C0 c/ A! h3 z6 D" ~
record-data
5 m- r; H4 ?. `; @0 _ ]: N; r1 W7 T$ ~
) D: ?' E6 C+ j g& R& |' H ;; give the turtles an initial speed) m. U* ^( |8 i+ ?" F
ask turtles [ set-car-speed ]5 C* S& K) ?0 }+ W* g/ c
( G! j3 Q+ ?/ L* E3 j: `% p
reset-ticks
" | r; C( i: _+ y; M2 xend
6 X! J& J( `9 h+ @" c0 r
1 y. n3 l9 t+ e$ c; A5 f) Q/ E;; Initialize the global variables to appropriate values
4 P. \* Y0 U, T* \6 u. Mto setup-globals4 M5 H) ]4 u# ~3 x6 f( ]
set current-light nobody ;; just for now, since there are no lights yet' i- p7 P/ ~: t T: f, H. K# q. @) e
set phase 0
6 M2 i& ?1 s2 p5 a$ d7 b7 V6 J set num-cars-stopped 08 O8 b5 W# X+ C- T
set grid-x-inc world-width / grid-size-x
! h/ S6 |( V" ~5 v set grid-y-inc world-height / grid-size-y: H0 b. N6 Y0 `" s& Y& v0 m
/ }. o6 a7 M; m7 w# {. I, l7 b+ F
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary/ g5 P+ g$ y" N% a+ D1 b# V
set acceleration 0.099$ i$ ]& R; i' r
end
) ]$ e0 I. N: X7 I0 t7 p& Q4 W. b, v6 N0 v
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,( B; {0 E4 A' _% \, S5 |
;; and initialize the traffic lights to one setting
" _) F/ j# W) } fto setup-patches
w9 W) R4 @8 D; } ;; initialize the patch-owned variables and color the patches to a base-color* ^0 p4 V5 w0 U7 X0 |
ask patches
, _' n% h9 ~# { L B, ` [
) m9 j3 O/ Z/ ~- M, L ]( t' V; Q set intersection? false8 V A$ S# D; T: }8 T
set auto? false
7 y1 [" J" [& ]( h4 o; t, e3 n set green-light-up? true9 q# J* A% U! E/ Z% D' A
set my-row -1' T1 Q4 W" X" y. y4 B* ?
set my-column -1$ }/ g& G* @, J: q- `: c( F
set my-phase -1' u( C4 Q: K8 k3 K G
set pcolor brown + 30 l2 t' X. W% G: W* O$ Y$ J4 C
]( {! {$ X4 h8 {$ A
0 I( y; s- J G) Y ;; initialize the global variables that hold patch agentsets" q1 W, H1 E# v0 A7 y3 k- ?, q
set roads patches with
$ h6 {& J% y) j2 N) g( k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( a# y* e" V. E9 o8 V (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 ?2 m7 g1 L7 k' q" T set intersections roads with+ c" m: P) o6 z# n" |( Z k6 e
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
3 o! Z8 W4 T) [4 A0 x8 w! Y% x (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: y1 X- x! {, h! {: p7 x! D+ R. v! ^* l/ v+ s4 f6 T
ask roads [ set pcolor white ]
( k0 a5 r/ p! m setup-intersections
* q, a7 P& K$ |% yend
; D- Y% P; l5 c# v; v其中定义道路的句子,如下所示,是什么意思啊?
% G: K' _5 e) f; ]$ a' p6 p set roads patches with: G! Y" v5 [7 n% g) F" A0 A( ~
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ N+ C% p; C$ ]" k6 h
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ H! [" x" r1 W. ]9 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? |
|