|
|
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。
. `" g7 |/ M$ ]! Q5 p1 d8 r5 Q6 @+ inetlogo自带的social science--traffic grid这一例子当中,/ t) o: }/ N6 v* a
globals }# e+ l1 v8 c0 z+ @# i7 }
[7 t5 p0 N) t, L6 j. P5 c
grid-x-inc ;; the amount of patches in between two roads in the x direction5 V/ d: {* M; p
grid-y-inc ;; the amount of patches in between two roads in the y direction" R4 x7 i0 R! y& l4 M
acceleration ;; the constant that controls how much a car speeds up or slows down by if8 Z' u/ w/ @' z8 I, ?7 u
;; it is to accelerate or decelerate5 c: v; l Q( ^
phase ;; keeps track of the phase
1 [8 h3 q4 b; _7 Q" h- ^8 i% \+ l num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure( W0 J2 `; U* k% @( T
current-light ;; the currently selected light
`. \- ~; a0 A, \
( G1 }/ [: m7 M9 d& ^4 C2 L9 K ;; patch agentsets; x( q2 A1 ?' S& N! w
intersections ;; agentset containing the patches that are intersections
+ G6 a" j3 {3 M6 W4 S. f/ l8 d roads ;; agentset containing the patches that are roads+ n* E1 [# U% m9 o$ _, n
]
) @) b" n, b: G& H* I' P I% R/ P T2 t" M' {8 M" T. i
turtles-own
9 w0 P$ r# s6 P2 t( x; Z[+ c8 }5 ` R7 F% Z: a" z
speed ;; the speed of the turtle
0 x B( A- s, {2 M$ g3 X up-car? ;; true if the turtle moves downwards and false if it moves to the right. T0 C* O7 i% B
wait-time ;; the amount of time since the last time a turtle has moved
6 r2 D; j. u& P4 v' x6 j/ O* I/ @]
/ N6 A3 m7 d! f) t( {9 p5 \- t2 S5 V0 m4 _, |' X9 p
patches-own
# f& t% w. r r; T/ W: ~$ `[0 b3 u! ^, a6 N; N5 z; k
intersection? ;; true if the patch is at the intersection of two roads4 p* t+ B* A* l' F4 f5 `$ ?2 ^
green-light-up? ;; true if the green light is above the intersection. otherwise, false.8 `) m) G. F: v/ z
;; false for a non-intersection patches.# b& z$ c" h! ]. I# H' e1 H! X* a# t
my-row ;; the row of the intersection counting from the upper left corner of the9 D4 F: ^8 V( O" y. S* N
;; world. -1 for non-intersection patches.
7 x# U4 e1 {0 F* J7 L h my-column ;; the column of the intersection counting from the upper left corner of the$ q5 F/ q( e" ?9 {+ v# G
;; world. -1 for non-intersection patches./ |2 O, C8 T9 Y0 Z4 U4 l9 _
my-phase ;; the phase for the intersection. -1 for non-intersection patches.+ B3 g* Y( h5 z) B5 B: l
auto? ;; whether or not this intersection will switch automatically.
3 j! A9 r& O+ a% i ;; false for non-intersection patches.
4 A7 p1 Y9 _( r% {- ^]$ v' ^! V( @0 ?5 j4 h2 }* B
/ ?5 S8 L3 ^1 @5 p
( X. R# o g' Z+ P7 P# W' U
;;;;;;;;;;;;;;;;;;;;;;7 ]/ T/ e5 e3 ?. k
;; Setup Procedures ;;
' [5 _. s. H. o- q1 @0 S;;;;;;;;;;;;;;;;;;;;;;
# E) {$ Q7 q8 {1 v1 H. ]0 q9 Y& M' E$ U' O' J( Q
;; Initialize the display by giving the global and patch variables initial values.
) u; N9 }2 u3 Z5 L;; Create num-cars of turtles if there are enough road patches for one turtle to
! z% h3 A. c2 v$ C3 G& }' _* c9 J;; be created per road patch. Set up the plots.
' x$ O/ }- ^# e* R4 `0 d+ vto setup
- S3 K X9 K# z; b ca3 H, P7 f6 v5 c- Q* H! }) z) P
setup-globals v: s' _6 n8 {( m
+ ~4 W: G1 O0 c& G7 \4 z6 R
;; First we ask the patches to draw themselves and set up a few variables) `: k5 ?8 }5 P' e
setup-patches
5 n; v: U$ F! z1 U' l M; k make-current one-of intersections
! s& y8 q! ^1 O2 M8 `) n label-current
6 q9 e! p. {; x4 W W) O6 D* N3 W% S
set-default-shape turtles "car". T1 x7 Q* f0 `7 Q
) s& H: n3 j( v. D$ O% C0 k& t if (num-cars > count roads)& J4 C% x m, h, [5 D! c
[: m. A6 u3 S' z* D3 _
user-message (word "There are too many cars for the amount of "
) v8 x1 Z0 A/ s+ U0 E) p "road. Either increase the amount of roads "
1 G W7 D( y, E- v3 r "by increasing the GRID-SIZE-X or "1 C9 T0 A% h0 x3 ]
"GRID-SIZE-Y sliders, or decrease the "
. T2 F8 N4 h- `1 l4 o "number of cars by lowering the NUMBER slider.\n" t; l8 J& b5 S7 N! w; B! D; z
"The setup has stopped."), V1 N% c: F" k% u6 a5 ^2 N
stop
1 K5 ~' t/ ~% i+ w0 f8 B9 d' o ]4 v+ c) C9 Z2 c* R, M+ s
% \3 h. F3 v. T# V
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
m2 d# o2 U1 t7 f# C: M crt num-cars
6 N8 H, t) }! |" ~, e [
, `* p+ w2 V% I setup-cars) e' V" p5 ^3 G9 t) A
set-car-color
* M7 z3 X+ U) z8 h+ } record-data7 T+ S% y% z$ t# J/ a- e) m
]
* E2 e, d# ~5 m5 T& r. q. O! q: \/ S$ @. |) ]0 r0 N% q) H
;; give the turtles an initial speed4 I/ b- A4 J" O6 P1 ]' R# a5 f) g4 r
ask turtles [ set-car-speed ]' F7 Q; A1 l- q }+ R* K7 A
+ f2 a% U8 f1 P n& i
reset-ticks8 j! ~ _' Q0 b- s O" p
end
/ N9 @3 p" H" r. f4 j4 F. ` E: a+ N& ?, A7 M$ J4 p) L4 [
;; Initialize the global variables to appropriate values
3 T( n: d9 B# ]+ Hto setup-globals
5 X* U0 T8 S4 ]6 l3 ^5 B set current-light nobody ;; just for now, since there are no lights yet# J, y& R, J G4 [% ?$ Y1 [
set phase 04 a, [! m7 g) W
set num-cars-stopped 0
' L% G, ~/ w% ]% G" L2 Q8 q a/ |# d: i set grid-x-inc world-width / grid-size-x' B2 U& Z+ f) z" C
set grid-y-inc world-height / grid-size-y# a, A/ `' a$ K. H, G* t' y
5 p5 j3 q& e' x9 K- d! {2 Y
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( T s6 b; p: R5 ~4 _ set acceleration 0.0994 _( p6 J' f! W
end
0 }/ X2 `3 v9 q% X! D9 _' W0 `: \. G! C) Y% y! _
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,1 H5 T2 d. B i) N" e0 L! u6 m
;; and initialize the traffic lights to one setting) {+ b1 O% {2 g8 f6 L3 O
to setup-patches
) Z5 J i, K, ~5 l0 Q( Q1 G7 Z ;; initialize the patch-owned variables and color the patches to a base-color1 S m2 l! v& w* e
ask patches2 t5 S' c6 d+ {
[
3 |; {5 A* N+ V% j: P* L$ B( n set intersection? false7 t8 y5 M: P' Y
set auto? false
0 a+ L5 N! Y8 q( [" V# ^ set green-light-up? true
, k* I Y, [3 I+ R) g set my-row -1
0 [% l& k2 w* f+ r; R( ~3 T" }" E5 [ set my-column -1
' s1 G( y& p# Q: M* P5 ] set my-phase -1# v4 w# c" ]6 e( i4 E3 P, M
set pcolor brown + 3
# o7 U8 n4 B( I9 O9 [ ]0 x9 ~6 K/ X' y0 ?( s& X
! ~4 l; C+ Z/ y8 i- E ;; initialize the global variables that hold patch agentsets, f* e+ h* L5 q F M
set roads patches with- B# ~5 o( @: T8 N8 x* P1 J
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 W# A8 N: p1 ~" a& T) ]* ~) L9 o# }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]! y2 a5 z q8 j( z9 z, a
set intersections roads with' Z% @- c0 W; y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
! M) y E) i O' N (floor((pycor + max-pycor) mod grid-y-inc) = 0)]! Z5 y6 x t9 [& |
( d% k! K1 r* v0 [
ask roads [ set pcolor white ]$ @3 j: n. B: ]1 D
setup-intersections4 X4 v; a+ c1 J( |- P M( k
end, f: Q: D% ^' ]4 U
其中定义道路的句子,如下所示,是什么意思啊?+ v+ U' [5 e* J5 `: s/ T3 D/ Y
set roads patches with
: Y2 p$ `- \0 N7 e' l [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 w/ }9 w' l* I2 Q/ F (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" g( i9 B b0 I
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? |
|