|
|
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。& d- J X! f7 a6 I
netlogo自带的social science--traffic grid这一例子当中,, ^: l7 a4 |( A9 B" l- k
globals
7 @0 |* n. D, S, t" j- `( S; k[
: G+ O0 I6 r* ? grid-x-inc ;; the amount of patches in between two roads in the x direction6 f! Q& O# z3 l
grid-y-inc ;; the amount of patches in between two roads in the y direction
5 h. g3 o; z5 F! q acceleration ;; the constant that controls how much a car speeds up or slows down by if0 o& h6 S0 g: H" i( W, s, N2 y G& s7 c
;; it is to accelerate or decelerate& J8 F8 m6 c- b$ J: o& w: Q3 p
phase ;; keeps track of the phase
; @) `! z. M4 F: N2 y# r num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
$ [7 l6 n1 x9 [' Z! R+ n' H current-light ;; the currently selected light
& T# n4 Y! I! k* N" O; j, ~: ^2 K* a0 c$ X
;; patch agentsets
! u8 u) [6 J1 D4 j( z; D. H intersections ;; agentset containing the patches that are intersections
1 h1 [9 u) k. U5 U' y: H2 `7 _ roads ;; agentset containing the patches that are roads
0 [" T+ Z' n5 K0 s4 h]; a, \1 v1 c+ |4 B( f3 v
$ D9 ~8 X& ~* @6 L+ B+ q& ]" hturtles-own
9 e9 K# l) D7 r/ s+ o[
|0 G# I1 w ?+ e+ H& ] speed ;; the speed of the turtle0 }, F% z( Q6 u
up-car? ;; true if the turtle moves downwards and false if it moves to the right
' \& Y' j6 f* F2 e4 X% V+ J wait-time ;; the amount of time since the last time a turtle has moved
6 ], U% Y L M]+ x6 S* f/ @& B# m1 {5 _
9 v* ^9 [6 b& {+ y5 wpatches-own! i$ Q [& j3 o
[
4 s3 F( |$ q' E1 H% d intersection? ;; true if the patch is at the intersection of two roads
+ p0 E& v& d1 G4 g green-light-up? ;; true if the green light is above the intersection. otherwise, false.) {3 _& h- M7 w# M8 a+ j
;; false for a non-intersection patches.
! R' ]# B E; K# c, J6 O; z0 {/ j my-row ;; the row of the intersection counting from the upper left corner of the
6 } S1 g" z$ R1 O- M ;; world. -1 for non-intersection patches.) Z: }# d2 l8 k2 d ]% g" q
my-column ;; the column of the intersection counting from the upper left corner of the
4 d7 ~, ^7 V# k2 g/ m' X ;; world. -1 for non-intersection patches.
- o E1 ]& d0 x) }# |8 o" e my-phase ;; the phase for the intersection. -1 for non-intersection patches.0 P& p7 R6 J4 r$ w( E+ Y6 v0 q( `# J
auto? ;; whether or not this intersection will switch automatically.
8 T4 n/ f7 G; e ;; false for non-intersection patches.
: O& _, `# S+ J0 m0 i], h; T9 R6 S( r; o
+ z+ v- F: S9 r3 Z4 w6 {0 v+ B, `" {% B$ C s0 [' p
;;;;;;;;;;;;;;;;;;;;;;3 H6 H3 E! ~' h
;; Setup Procedures ;;$ `7 y, Z9 r( \" _6 g7 n+ r3 N3 ?
;;;;;;;;;;;;;;;;;;;;;;
0 P$ U: b0 E: }9 x( z+ u
- e* l/ m8 x) k( R;; Initialize the display by giving the global and patch variables initial values.
, @" k* n |% I8 Q+ s;; Create num-cars of turtles if there are enough road patches for one turtle to9 _: ]+ c/ N, p" p3 [
;; be created per road patch. Set up the plots.1 S/ P' r% { f: E5 F/ y# N; x$ j+ v# y
to setup
" \5 Z; C. T, b ca
S: @ |( m7 ?: g% J$ o; w setup-globals0 h. p1 n/ N* r, ?; g0 W4 {
" }6 ~; C- g b" Y1 w s
;; First we ask the patches to draw themselves and set up a few variables6 P1 V/ V: m- b5 Y V
setup-patches- h' a7 Q6 U3 _0 s, r' M6 _
make-current one-of intersections
2 F& ?$ r& l" n! L g/ N7 n. v( M label-current8 P8 G: p4 d: p) z# L7 z; B' U! B* w$ L
/ ` h& G( Z7 _: D2 D" w set-default-shape turtles "car"
( o% ?& k5 w% |! z- W4 y6 e# g1 y. A( r1 F- U$ S$ H
if (num-cars > count roads)
( F0 Y( Y/ L I3 e: }) ~ [
+ k) z) Y. Q; y2 L( c! A8 v) | user-message (word "There are too many cars for the amount of "
+ @- y/ C" g w5 i0 q) R: D "road. Either increase the amount of roads "
2 N: G( ?% b# W "by increasing the GRID-SIZE-X or ": b7 c0 a+ ]& q# x( s
"GRID-SIZE-Y sliders, or decrease the "3 q8 i% X* x! H. o" V3 s: X6 ]
"number of cars by lowering the NUMBER slider.\n"
+ d8 ^/ D/ b; J$ p* E$ W7 H "The setup has stopped.")3 I! @& w0 h# ?1 h
stop
% ?/ g3 y+ w5 Z9 q; {7 {/ E ]
* `* @4 _' B/ T5 P+ P9 P5 |& q5 ^7 J" Q: e
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
5 D9 h# H8 J$ r3 r/ ]2 r6 y crt num-cars; \" d# O: |! z1 y6 D& P& f7 W6 j% w' j
[
! Y* ^& k/ o) R setup-cars
4 h& V7 Z/ ~ j1 Q6 D( I- f" [, i+ D w set-car-color
) _, ^% t% k4 y7 ~& k' i# x record-data( a r1 d- Q/ ?2 t; l
], k% h9 t& E& B* Z) d% ?; s
7 |1 K6 i, X, s1 n5 M ` ;; give the turtles an initial speed# g5 R7 Z. S) L0 X
ask turtles [ set-car-speed ]) S6 a, o# z+ L, _* E$ G
3 _, y4 I. e! d* {
reset-ticks% d. d+ s$ n2 h h9 P
end
" ]. O% f5 j' |; `' m4 \" B( T& j/ t6 V5 A7 P$ S- T; I: N
;; Initialize the global variables to appropriate values
6 ~* o8 o' |, C+ @3 T! P9 R& pto setup-globals
9 j) H" n/ ~2 q' L, q set current-light nobody ;; just for now, since there are no lights yet) u" M. v$ o+ Z
set phase 01 ?: T& Z3 Y. p5 u, P; G
set num-cars-stopped 0
' Z7 i0 D$ M+ d4 n: y5 a- ^* T set grid-x-inc world-width / grid-size-x
2 m [, ]& U ^% l5 y set grid-y-inc world-height / grid-size-y* _' `( q# A1 ]
" p4 n; n4 d5 m. T* E- B
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# E: Q+ _1 Q/ E0 D0 p0 k& ^: D set acceleration 0.099
. C, \1 ^) b8 Z# C5 kend7 f. c: z& ^/ ]! M
* y; A( M" N; _, n. s7 m
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,' n/ Z5 d. r) ~) u/ W4 n9 g
;; and initialize the traffic lights to one setting0 ]3 \8 d2 I8 o, w7 Q# G$ X$ r: m
to setup-patches
. l2 U$ M* S3 p* m; u7 J! ` ;; initialize the patch-owned variables and color the patches to a base-color
. S$ E Y6 }3 D# s. Z1 t5 P ask patches3 r) I" |8 c4 _
[
) z! a' q% N; t. K3 T+ {( ]5 K" p set intersection? false$ e: Z. P0 C0 q
set auto? false
# Z# w" G0 D1 G3 b' }. n+ Z5 @ set green-light-up? true
- z1 D# r+ f: H5 I: W7 J/ W+ @9 L# y set my-row -1
8 O1 l0 D, Z. Y# Z set my-column -1
% ]* K, l/ d @6 W Q set my-phase -1
4 _& O( D; O1 ] set pcolor brown + 3( }+ {" T @% H
]+ @/ _2 s! W& D% U. A% v& R% ^
4 a/ }0 n1 J& s+ `
;; initialize the global variables that hold patch agentsets
, p; C* G) o5 l set roads patches with
; N- T" A2 f4 x) \, T, o7 x8 c [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
5 P1 N0 \, u% ~9 }0 Z$ ]/ x; M' T (floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 [! ?. s1 C0 } G# x( A
set intersections roads with7 D4 |% W' @, h. a0 h0 g
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
% D% s) ~& N9 D" T7 T" ]2 o (floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 C( K& ^' Z M$ I: R ~, K
j$ N, v E) }4 o ask roads [ set pcolor white ]
5 Y+ p( x/ j- l) A# d setup-intersections
- |. e! I, ]+ I1 e# Uend
7 T3 U1 ^8 w1 q, m% D其中定义道路的句子,如下所示,是什么意思啊?
- x" i! ]9 R `1 E# v k set roads patches with
$ O: V9 r* W0 ~0 p [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ x0 p3 [: P& f1 A1 x# P2 Q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. A2 u+ P, x. ]+ r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? |
|