|
|
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。
! b' P/ |( D, X2 \' inetlogo自带的social science--traffic grid这一例子当中,$ ~7 o5 |" ? `) E6 Q% Y! a, u z
globals0 g6 [' N! O; q
[
% g9 R; |& I! H- H s0 R4 @6 C0 @ grid-x-inc ;; the amount of patches in between two roads in the x direction" N4 P8 R/ }; U. j
grid-y-inc ;; the amount of patches in between two roads in the y direction
" o6 o" k: ~7 X9 z. m1 V* a acceleration ;; the constant that controls how much a car speeds up or slows down by if; U5 U3 q% A8 H7 o3 A" S
;; it is to accelerate or decelerate$ v8 Z. A! A6 l- |5 ^+ `! z
phase ;; keeps track of the phase
. u6 E* _. T3 m num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
) S. V. x4 |( n9 e0 \! K# w current-light ;; the currently selected light% Y/ [5 k1 N/ O* ?8 y
& N1 v3 @/ i, m U ;; patch agentsets. X" c1 ?3 y- b$ G( i+ N
intersections ;; agentset containing the patches that are intersections
/ U2 v6 ]9 l0 b& w% _ roads ;; agentset containing the patches that are roads5 g3 O* J3 j& S- D! d% D
]6 d! H% e; q: n( e
& [4 u" w- @7 u) q0 v3 h& ?1 Iturtles-own7 \, G. ?# d% F% t0 Z/ r; S+ q( {
[
/ A4 t" S5 E, T speed ;; the speed of the turtle' q$ e5 ^- U5 a+ F
up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 e/ Z' _; Z2 [5 @ wait-time ;; the amount of time since the last time a turtle has moved* y1 ?- I, `. f
]
* C; Y& {* Y* [, ~2 W7 W. x9 \5 t( i4 s: \8 X" j7 h
patches-own
4 h* [ }+ m1 W[
2 J. w, D5 [$ x, T0 K intersection? ;; true if the patch is at the intersection of two roads- O, J( u# {* x3 m& J8 p
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
9 C9 [5 K- I3 [: B' _: I ;; false for a non-intersection patches.3 i# h( X, v! G/ ~( O7 N( s
my-row ;; the row of the intersection counting from the upper left corner of the
- ?' u; ]1 f. _8 @. v" k4 F ;; world. -1 for non-intersection patches.
0 |' Y' f" R4 H M+ ^ my-column ;; the column of the intersection counting from the upper left corner of the( v7 G; y* v% S2 G# A
;; world. -1 for non-intersection patches.' h3 S* m2 f; v9 U2 j# K! B
my-phase ;; the phase for the intersection. -1 for non-intersection patches./ I) E* `- e5 x: j
auto? ;; whether or not this intersection will switch automatically.( z T7 l: f% M$ y! N" e8 E$ u6 j
;; false for non-intersection patches.
: w* I5 h9 C. H* K]
. C/ [! [6 P2 t9 y# `& |/ G- b! ^3 @6 z6 E& }$ ]& K( | f
! a& Q4 o; D/ O; l. b* E- x;;;;;;;;;;;;;;;;;;;;;;
{9 c4 ~+ v q; p7 r;; Setup Procedures ;;
, Q9 v0 B! f3 L. A- f3 E;;;;;;;;;;;;;;;;;;;;;;4 q- g7 |: N5 W
6 N, g" I' Z2 y. O" M8 ^9 t;; Initialize the display by giving the global and patch variables initial values.
( M% k- T H9 N" Y4 R;; Create num-cars of turtles if there are enough road patches for one turtle to
# n5 b; }1 c& |% O: P+ {;; be created per road patch. Set up the plots.1 y5 g2 e5 d c/ s
to setup
7 e! h7 B5 H# l+ f8 |! | ca
4 T0 `) ?3 ]7 k% p* g/ j f' m setup-globals
* |2 p, L, Q* ?& K4 p6 \- d K: g/ e1 Z5 y
;; First we ask the patches to draw themselves and set up a few variables' y2 E, ^3 r( b' r) k! y: c+ Q
setup-patches' g- @1 R) K8 Z) Z, q
make-current one-of intersections" x7 w' b7 n: M, \
label-current/ n; I0 g, j) B8 K6 A
: m9 z. R( v" ^( b set-default-shape turtles "car"1 o6 o9 o) J; w, z% o+ w! \
) ?. V2 i, j8 R Z1 o* C- T if (num-cars > count roads)
1 S; q$ I/ H0 L6 d+ V+ `5 j- H [2 ]% n2 C% c% n+ a4 \$ t
user-message (word "There are too many cars for the amount of "4 m L! {) b. [6 _0 o' g6 F
"road. Either increase the amount of roads "
) s+ S9 w7 G1 j$ O. i$ k6 ?' L; ` "by increasing the GRID-SIZE-X or ": K& e$ U4 ~3 @
"GRID-SIZE-Y sliders, or decrease the "
: P, W) D' Y) X. R3 D "number of cars by lowering the NUMBER slider.\n"& s) I& E% k% s5 P$ k+ M3 Z* a. g
"The setup has stopped.")
% o+ S, A, i2 `2 U1 |; m stop7 C; {2 @% p9 P- U$ }( c- N2 x
]
6 k) B- u+ C* F6 U# U, Z: D
( ^" E- W+ t9 |7 R- w( o, J/ {4 D9 U ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color2 W2 c0 s/ p" E2 p9 D, l8 N
crt num-cars
* g0 A* I8 c( w/ [5 q [7 h: J0 m* l) m! Y& t6 M, P' C G
setup-cars; c: m" a7 {- F2 W
set-car-color
( h% U ^& a$ B+ G/ P! M- | record-data. S; J* g3 S) v. O/ _& V2 I
]
# `; J* D0 l$ e6 B6 c9 K
* }* Q. W( W* H4 M9 i ;; give the turtles an initial speed9 [7 v* ?- e: ?8 N
ask turtles [ set-car-speed ]
8 c- u( j* ]2 n3 b
^7 O, G$ r4 j, a7 \8 q0 ? reset-ticks
1 x1 k& ?3 Y! B, T n) xend
) g' b( N" n! `' H3 ~: M" K. b& M. [0 ^1 B( y; P6 H* h# R
;; Initialize the global variables to appropriate values1 L. s, [' c b) n4 y' X7 j
to setup-globals: N: V; H/ p, E; k/ D: D/ M
set current-light nobody ;; just for now, since there are no lights yet
# y7 l5 m( ?( a set phase 0
$ Q6 i' O; ] [ set num-cars-stopped 0/ |5 Q1 R! @# T7 e/ P, g
set grid-x-inc world-width / grid-size-x
7 I. ?( n3 }) N4 F set grid-y-inc world-height / grid-size-y
) V1 u6 Z8 C) i) h6 I, R# c+ u7 u! T$ ` S
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
4 Y7 f4 E' Q4 z( L% l set acceleration 0.0995 d; b9 S8 E0 \$ }) m4 O3 }7 g
end
2 v- T' B( S! Q' a, Q& q! Z
; g/ `! p- q# Y* y8 ] R9 h) `1 o;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
% p+ ^1 M, E2 p+ ^) J* W;; and initialize the traffic lights to one setting
" c6 J2 O4 i; t7 H; W7 ^to setup-patches! D, D, j- m4 `1 g
;; initialize the patch-owned variables and color the patches to a base-color( ^9 f5 S9 j' t* N# E z( t
ask patches' k( c5 p; h. G; Q
[# H+ ~7 y4 F2 D
set intersection? false
' c1 H- T H& W( p/ x+ c* u set auto? false7 q, v. I# U6 {; K1 k; H
set green-light-up? true
2 {% C7 {/ t7 L2 h5 B# \ set my-row -1
- J2 g# \% s# B% j' R3 F. V% l1 ? set my-column -1" I8 \& m: h: M4 i! x* a: k
set my-phase -1
& Q$ y) M: D5 g' I& K6 d( u set pcolor brown + 3# a9 K, t7 q) `1 @ X; J
]
& h$ ?: D( L) ]1 T' B! p- ]0 ]
& o* }8 ~* u6 h& \ ;; initialize the global variables that hold patch agentsets
+ h, H2 {- e3 i; o! [ set roads patches with
5 G t1 X& O& A( g. Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ ~* k7 i o i2 z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& I) _& P5 t3 j/ r( s& t
set intersections roads with! @$ p( _7 M3 }/ L0 V
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( T% j- a& Z/ D/ s' ~
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ @9 F" j: O" v% Q
' d/ b! w6 P3 u ask roads [ set pcolor white ]
4 G' @$ E' z& A( ?5 w) a, @ Y setup-intersections
' Q$ Y; M. e% i- ^+ ~3 r3 Xend* }% g8 p1 A" }% d
其中定义道路的句子,如下所示,是什么意思啊?
& c, P3 j+ a0 D+ I1 Q: H! ^ set roads patches with
) F' y0 g6 n+ C, \" H, ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ B+ {2 L* i/ E. O# F% _. i0 m5 K
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% {5 T/ B# {, O6 g" }! J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? |
|