|
|
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。
) [/ I2 d- L" Nnetlogo自带的social science--traffic grid这一例子当中,
* M& ~1 t3 I5 ^globals" v8 e$ `: H3 {- f. J3 O( d# [
[% f; U) [- T: n; b! z
grid-x-inc ;; the amount of patches in between two roads in the x direction; Q/ }7 ^* `, ~* J
grid-y-inc ;; the amount of patches in between two roads in the y direction
' M; P& I4 s# G acceleration ;; the constant that controls how much a car speeds up or slows down by if
- K$ p; e* P, V% b5 f ;; it is to accelerate or decelerate% r! j3 r$ [' x9 h1 B {0 W
phase ;; keeps track of the phase* x/ ~& b/ @; f9 V
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure5 ^& T) _& y6 A7 }6 E
current-light ;; the currently selected light
* O+ Y( \3 V2 Q1 }$ e9 N& }! T* J% C8 w, `
;; patch agentsets' P* h9 U( [& Q+ M! H1 C/ J$ o
intersections ;; agentset containing the patches that are intersections1 M8 H Y" {9 h. p( c
roads ;; agentset containing the patches that are roads
: L( M) B5 f& L2 q+ |' M/ H/ ?]
+ ~0 K9 F" E7 Y! Q. T% R, K/ M# ]
1 I/ a7 {0 I" f Q4 G; Gturtles-own( p' y4 Z/ z9 V7 a4 \
[/ V/ j; K* A( o! h% t6 a& R- {
speed ;; the speed of the turtle; g6 H; ~6 `+ L5 @& P. r
up-car? ;; true if the turtle moves downwards and false if it moves to the right
5 C2 h0 O7 o; j6 e! V$ R& S R% { wait-time ;; the amount of time since the last time a turtle has moved
5 o( L9 F5 y! l% E. Q], O( ]8 ?9 k; F4 |5 e" f5 B# }
' b& E7 ^: }( y* I8 Cpatches-own7 ]! V% M' H" ?" }
[4 i) N8 v$ }& |
intersection? ;; true if the patch is at the intersection of two roads
x3 ~7 \* B5 f* l green-light-up? ;; true if the green light is above the intersection. otherwise, false.4 `" _# d* C* i. y# }
;; false for a non-intersection patches.
& p* Q+ P' q" U9 j, F1 A( ~ my-row ;; the row of the intersection counting from the upper left corner of the
% d0 w2 R; ~: j7 @ ;; world. -1 for non-intersection patches.1 \, O; m: T- T! o+ i0 V H5 `; M
my-column ;; the column of the intersection counting from the upper left corner of the
- [: _) v/ X' L$ d ;; world. -1 for non-intersection patches.% Z5 B+ _ |8 k
my-phase ;; the phase for the intersection. -1 for non-intersection patches.; e$ Y' \$ [9 h8 r+ W
auto? ;; whether or not this intersection will switch automatically.
[- z1 b* ^9 U: {% M ;; false for non-intersection patches.; z4 b. ~( M; |
]
- i8 r" y; }% A
) j9 Z4 L- m0 P0 M
; l5 ?8 w% z. g6 _8 u" a0 {' Z;;;;;;;;;;;;;;;;;;;;;;
7 ~; p5 c0 P2 k* f) |8 g;; Setup Procedures ;;7 r# j+ j% B6 K4 Q4 @4 \$ Q5 r5 k- ]* _
;;;;;;;;;;;;;;;;;;;;;;/ l- D' N. @3 b
6 ^; [, L9 a; ~: @' T7 N& O
;; Initialize the display by giving the global and patch variables initial values.: t* t0 i- N0 h6 b
;; Create num-cars of turtles if there are enough road patches for one turtle to
% x3 F" o8 B, p0 q;; be created per road patch. Set up the plots.3 \) J) }6 z" f" L7 p
to setup" \' E% c: N6 [6 C# X
ca
& c& k0 Y% x' S5 } setup-globals
4 R2 q5 m% @! d, |1 i3 Z! s: ~2 Y* w8 {
;; First we ask the patches to draw themselves and set up a few variables7 }/ x4 i1 z5 b# x+ F( k
setup-patches
3 k8 w P2 u. N5 q) n5 x make-current one-of intersections3 {; j) p3 m& o8 T6 [& D
label-current) S" J( g) b* _8 w- s: T
5 X1 f# p5 a" B4 ~ set-default-shape turtles "car"4 U2 b p% x1 }8 K! j) H
2 M1 d! G5 {# C( [ if (num-cars > count roads)0 K9 m* r4 ]0 |2 h9 s
[2 L/ t, v: W) |! t$ l* A- a3 W
user-message (word "There are too many cars for the amount of "* {9 z) {- E3 m' [9 E
"road. Either increase the amount of roads "
) q* f5 I o, w "by increasing the GRID-SIZE-X or "
) X7 m) B- F6 `2 ], ~- f8 p) O "GRID-SIZE-Y sliders, or decrease the "
( O3 g" v1 }. K; _+ J "number of cars by lowering the NUMBER slider.\n"
. |+ ]# F+ _/ X9 g5 {& k "The setup has stopped."): F4 N; G0 @7 \
stop, g9 v6 Q4 q1 U- v
]
, `- ^; J% U, A& x/ \! S/ d( O4 V) x8 Y4 L( k. v: V; {7 O
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
0 {$ p8 g' x( i. |5 E8 [: |) c& L! [) ? crt num-cars
5 r7 H) N! F: }2 D0 f [% X) ^% {- Q/ T5 r7 O
setup-cars8 `. W* n# ~6 I' H; E
set-car-color; X# v- M/ w4 l
record-data
7 @0 P9 x0 Q7 X; ~$ m2 m% J2 B$ V ]9 s; d. c( p) x- O' d
% {8 g% q4 H8 R* {, Q5 m% ? Q* G ;; give the turtles an initial speed
- a; G$ Z- u5 X" B' _ ask turtles [ set-car-speed ]
4 l+ [! P6 H6 i" l7 H8 V" n& H
/ o- Y( ~; H/ h$ D& l1 E: | reset-ticks
! \/ E1 h3 Y- ]/ {7 n( pend3 y& m2 } z* Z& {2 n
3 ^1 r& s$ Y) n C, P K- d6 E;; Initialize the global variables to appropriate values! l! e# A \5 B* ?4 F- h' {
to setup-globals
! J* X3 R& q0 D: ?; J set current-light nobody ;; just for now, since there are no lights yet
C+ Z( O2 P7 n" a$ r4 t. y set phase 0
6 Q( g$ j3 x# M6 t# | set num-cars-stopped 0
% n5 S3 o2 M0 L4 r8 m% n set grid-x-inc world-width / grid-size-x$ `! q2 d7 t9 B7 x: L
set grid-y-inc world-height / grid-size-y$ u4 `, w) f# Y+ j8 h
) B* n+ T. a( L2 ?3 d ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
/ d; ^7 R' m2 _! ^, L, s set acceleration 0.099
7 w6 d6 G3 ?1 y1 Aend2 K( f) y: |. X
7 J w9 ` ^! y& A, d; d6 }
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 s @" A% D' j" k) @: W
;; and initialize the traffic lights to one setting
" i" X6 p W* k9 \to setup-patches
# X' r) S6 h& V5 u( n0 p) E ;; initialize the patch-owned variables and color the patches to a base-color0 P6 ` X8 r& `9 V
ask patches4 [0 [+ y$ j; F. W) S
[5 {- {: [# X: i) M, O
set intersection? false, e9 K: z( ~. s& T3 S5 x
set auto? false
8 m" K9 c( Z6 t, j! P1 w set green-light-up? true* H7 f: O7 @" a0 b1 \& A( `8 K" F; w
set my-row -1: e3 p8 l9 {# r
set my-column -1
; D& e# X, {5 g9 V$ u, y% ^ set my-phase -1
1 p% ~; j( T" ~3 J5 N3 ]( k set pcolor brown + 38 R' u3 B+ F1 T1 X: R
]
! D. ]1 s" y5 w8 l; p" @: ^
1 ]8 X r0 ^' V/ U. X% y) ^; @ ;; initialize the global variables that hold patch agentsets# d* S9 z# ]' c- E1 u7 D0 R/ M
set roads patches with
- o6 t& V# S. ]5 `- i& B5 T. e* t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: P) }6 L2 X# y; F( [9 F1 @( L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& B5 Q0 e" W& X! n& |1 j
set intersections roads with9 L' T. j' T7 V/ {# x2 X3 z! G( n9 j
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
0 W7 s! q+ e8 F7 \0 v (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; {. ?! R7 O+ O9 ` r* |! x) \* I7 p4 m6 m* ?8 V1 ?1 o: M
ask roads [ set pcolor white ] L4 E$ n; Q9 I( I$ ~
setup-intersections& E& f: S& L: z7 j2 [, t
end
: B- ^& A+ a/ _. n Y; b. ]) W- e其中定义道路的句子,如下所示,是什么意思啊?
; |" X; U0 ] C S! ` set roads patches with
1 [; S( o( j% U9 [' c' {1 w! U [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% u, F' ?: z5 H. ?# P" O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 v6 ~8 i% i7 E; g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? |
|