|
|
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。. W4 V7 H/ c$ k |. W$ Q
netlogo自带的social science--traffic grid这一例子当中,
' N' k# c w# {% K rglobals
1 d7 L( [: V8 W. T6 P( p N) x[
. A$ r# {8 ]9 j, s3 r( i; l, e1 H1 i. x/ e grid-x-inc ;; the amount of patches in between two roads in the x direction
* a; t4 x( M; g7 r& c# Z* V grid-y-inc ;; the amount of patches in between two roads in the y direction
- r6 C; y" F/ j& C8 ` acceleration ;; the constant that controls how much a car speeds up or slows down by if$ N! l% X% v# _
;; it is to accelerate or decelerate
: `! ^; V3 k) f' r8 G7 Y9 t phase ;; keeps track of the phase8 a, Q: ?: A: c/ F) `0 O
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure$ S8 b d( q2 ]; Q" a6 F* K. j
current-light ;; the currently selected light6 _- a B l; n2 D/ C$ {7 W
9 ~" H, A4 L9 f5 a0 x ;; patch agentsets
# f. C6 n* P! D6 y4 m intersections ;; agentset containing the patches that are intersections0 b M9 H/ w4 N! ^9 n+ L
roads ;; agentset containing the patches that are roads
5 |+ t, S5 r1 O6 g0 U8 x7 l]
( j( [* u8 ]4 H$ l% d9 R2 i, ^) g1 Y; ^" J* e) G F
turtles-own
/ K/ W8 c2 F$ U8 w9 P! G[
1 T; d. L- _/ E6 b( O# K speed ;; the speed of the turtle% @* V9 V. ]8 r& W; U; Y
up-car? ;; true if the turtle moves downwards and false if it moves to the right
! O# f5 j' w& N) p* l2 Q wait-time ;; the amount of time since the last time a turtle has moved J& Q: _/ Z9 u4 H( f0 s
]
2 ]1 k& P9 V, ~# G+ O1 e. D
6 ?3 u& M) }$ Hpatches-own. c- V. w# B E. n
[0 [6 ^+ {% w1 K ]! m
intersection? ;; true if the patch is at the intersection of two roads
1 y' a* }, b @$ r( x green-light-up? ;; true if the green light is above the intersection. otherwise, false.
2 _* y3 o0 [* i# P0 O0 y' s2 F ;; false for a non-intersection patches.* O2 A. E6 M5 }- F- ]: _$ X
my-row ;; the row of the intersection counting from the upper left corner of the
( F4 m9 ~3 l. _1 p4 n ;; world. -1 for non-intersection patches.
7 U4 {5 v% r$ } my-column ;; the column of the intersection counting from the upper left corner of the
5 |5 i! K* k' @& ^ p8 L0 k0 v ;; world. -1 for non-intersection patches.8 \5 T4 b+ t* Z0 R+ ~' w. V
my-phase ;; the phase for the intersection. -1 for non-intersection patches.* a& H+ E9 n8 _" Q; R
auto? ;; whether or not this intersection will switch automatically.
; r# i6 d6 ^! Z/ F ;; false for non-intersection patches.& T- i* _* g( A# d4 n |! \2 A, |
]$ N1 b4 G0 q5 o T) E6 M% C
/ D- v2 F, B: _7 e) r b, s, X" B
! H" v! p; |! O5 [/ K# k6 F;;;;;;;;;;;;;;;;;;;;;;& c4 i N, }: b% j5 U
;; Setup Procedures ;;
! J/ z% S/ n" n;;;;;;;;;;;;;;;;;;;;;;9 D9 J2 x0 j$ V0 E @9 W, K' C |
) H$ f* N# ]% B: ]1 k;; Initialize the display by giving the global and patch variables initial values.0 _6 v: ?0 Y# G2 v/ O6 R9 j
;; Create num-cars of turtles if there are enough road patches for one turtle to2 i. ~, b3 C8 A; M
;; be created per road patch. Set up the plots.
- A8 v/ b) w! H3 N3 G+ @to setup/ ~ ^! `6 }% d& v
ca/ a3 q5 y# h" V5 A- _# H; I+ B8 h" o1 W0 E
setup-globals$ T0 h- e. ^+ o9 a
2 v+ l i! N9 U% L# R( J+ N
;; First we ask the patches to draw themselves and set up a few variables
8 Z6 B! y5 i' }) C) K setup-patches
) _0 ]- V: M, I0 }: B- O% ? make-current one-of intersections- ?0 u2 ]! U8 R& H; f }
label-current! l3 B( f2 F) d6 H9 i. p
* s; ^& q! s% R; c) J! K
set-default-shape turtles "car"+ b* ~5 z {" ~- y. u
0 A; O- D' _& R if (num-cars > count roads)3 I- _) y, j8 [' X
[) U/ c7 u( B9 ]% n
user-message (word "There are too many cars for the amount of "
" x+ C# ~* F+ l( T* ~ v "road. Either increase the amount of roads "& p. \) |( m0 N# U7 s
"by increasing the GRID-SIZE-X or "
B5 v% G$ O% A! f7 Y) W& }( J n "GRID-SIZE-Y sliders, or decrease the "
* E9 L4 Y1 J2 H9 i "number of cars by lowering the NUMBER slider.\n"2 j0 k. [* l( M# V! S4 A
"The setup has stopped.")% g% [/ w2 V2 C5 M- z
stop
& h; [( Z3 ? ]' L5 m ]6 Q1 [- w: l2 N# M
: k% k" m m0 I4 k0 K
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
6 g; @2 a! N+ N# F) Y! f crt num-cars
8 C. M* r; g9 T6 u [% e; g. s$ y0 J% x+ [) i5 @
setup-cars
9 o, i2 g2 i/ _2 Y set-car-color
- E* o8 o: W) P: n9 i) l" a4 T record-data
8 P" G5 n& I0 C( T/ t' W# b ]! e( ~, s8 v" t8 J9 a% Q
( l5 I( n6 n; O! d' t
;; give the turtles an initial speed
4 {3 m1 x8 R- n, y$ Z! h4 A ask turtles [ set-car-speed ]$ p" E/ V) u7 H5 }! \: {
6 V+ y1 ~+ p" X9 B x
reset-ticks
- Z: I+ y& z+ f$ |$ x. N3 ~$ I% `end
5 V( h/ v' V+ `* C
2 C: X, }) o# p- |: k8 ~6 o v;; Initialize the global variables to appropriate values
# Y, C( J/ S x7 U0 O" fto setup-globals
# T$ r2 l6 Z; F: H3 w; P: y( f' } set current-light nobody ;; just for now, since there are no lights yet
: b6 Y' G9 Z6 g3 w7 A" I0 H% x1 L0 h set phase 0
2 p4 O. M: D4 t5 h6 J V/ Y set num-cars-stopped 0
/ i+ ~: Y2 g4 n7 b set grid-x-inc world-width / grid-size-x
* I0 R. U w: P8 l" Q J7 x set grid-y-inc world-height / grid-size-y4 t$ B/ R$ D& E! k
N% K5 B* V6 }/ F ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
! h5 y1 T+ @7 X M, ^3 f2 ] set acceleration 0.099! Z0 }" V: Z4 U! ]7 u6 m
end; k. U" X6 o* _' A, d3 t
# n( y3 K+ @+ O. s Y& p
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
3 X9 {+ {3 |' y `;; and initialize the traffic lights to one setting
9 k$ T$ Y E5 k e% K* Nto setup-patches
0 g5 B6 m2 w$ p1 \& k1 F ;; initialize the patch-owned variables and color the patches to a base-color: i& k2 S/ G' X) s* n
ask patches
- E0 e2 C4 S- \" z* e E [2 G) a6 P* d, k8 H t1 {' ?7 Q0 E
set intersection? false
' l) Q# v( B4 {4 P9 ?% a \ set auto? false/ ~; f0 m+ c: P+ E( q, Z9 d
set green-light-up? true
2 ?8 {4 t9 u* ~ set my-row -1: Y$ t6 X, e, p7 P* n- ]
set my-column -1
7 i6 S, b, S R$ E: w1 N& H set my-phase -1! V. W: q/ T, w" L& I& v
set pcolor brown + 3
. C" t8 z& |4 [0 g8 l5 W+ a ]
; G% Y- p" w) S w' v# ?$ s" s
! ]" e w: q+ p+ ^# j% `& W1 O4 p ;; initialize the global variables that hold patch agentsets5 W6 [# R a9 y/ \* Z9 L/ L: B
set roads patches with, s- G$ F k& ]* t$ V
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 k( T& z! ~4 L- O/ M3 h6 W1 B' V (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ N0 g; ~) V/ h/ g# \; g; A) Z) J
set intersections roads with
2 @; K: o0 Y0 A* A' T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and: M, J9 M; N: u1 q% g
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 f1 ~6 P5 d4 [+ U" u& ?# c% ?6 I, F- D' W5 F3 [
ask roads [ set pcolor white ]
, H6 c8 Z! f# z* Q$ o setup-intersections
3 y4 L) Q' w1 r, S+ fend
" q9 i4 h9 O4 X, c3 I! W其中定义道路的句子,如下所示,是什么意思啊? L( V1 j. k; w* ?
set roads patches with
: [6 K8 E: }/ e6 b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% K/ m- h9 B5 r- N (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( J# R* C. a+ X+ Z$ l( }, 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? |
|