|
|
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。
0 ]) Y, U3 r0 D8 w8 ~" ?netlogo自带的social science--traffic grid这一例子当中,
2 B& q. B5 Q% v4 bglobals1 O0 f; y7 O2 u$ o+ L/ F
[
" [/ N3 e% y X3 H grid-x-inc ;; the amount of patches in between two roads in the x direction
' q5 E8 a, V' d( X9 n& h& T- u7 I3 O grid-y-inc ;; the amount of patches in between two roads in the y direction
. j6 @4 }( S7 G! [; d9 K: A7 U acceleration ;; the constant that controls how much a car speeds up or slows down by if
0 z; o7 n& O7 \* E5 P- v% j ;; it is to accelerate or decelerate8 H3 C9 e0 L. F" j' l# M+ I
phase ;; keeps track of the phase7 _- C. h! q; J# o) d
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure2 `' v9 X1 \" _/ C5 z
current-light ;; the currently selected light. @ [: j" h6 L$ g
- K; B9 U+ ~9 g/ Z) O7 _ |6 a
;; patch agentsets
( \4 Z5 `% i, u- t! x: B intersections ;; agentset containing the patches that are intersections
8 B V& O! ` t6 T6 x$ U2 s) r roads ;; agentset containing the patches that are roads
* ?) ]8 e2 n! r2 Y/ w]6 @$ o; R; |, M/ P/ O* Y
7 p. H- P6 |% Q3 Y# k0 M3 Gturtles-own/ d7 W; Q' O/ S& }
[
6 g" R% e2 i9 j# M; ?- x8 E$ h speed ;; the speed of the turtle
) x* T& r' N0 d5 I& r0 M" g, D up-car? ;; true if the turtle moves downwards and false if it moves to the right5 O1 d2 p& e8 M
wait-time ;; the amount of time since the last time a turtle has moved
7 g* H& y/ i: a. A]# m4 v1 i7 l' r) K
6 {9 e1 l+ Z! N ~. f9 F
patches-own
$ {" A' h! V9 N& ~' w[
& D* W8 Y! q7 q/ A3 W intersection? ;; true if the patch is at the intersection of two roads
' n' Q& q" t% q/ C green-light-up? ;; true if the green light is above the intersection. otherwise, false.! S& _; `9 z/ H& T) U9 }* L0 ~
;; false for a non-intersection patches.
8 \' V# C0 y+ f( p0 ^! k7 ~ my-row ;; the row of the intersection counting from the upper left corner of the% A7 k6 U* ]4 o: Z. V2 N! f
;; world. -1 for non-intersection patches.! s# E' f: ]( a6 w( W( w+ u2 z& P
my-column ;; the column of the intersection counting from the upper left corner of the
5 O& p( o2 N; q8 F ;; world. -1 for non-intersection patches. |) E. |: b) c2 R. w
my-phase ;; the phase for the intersection. -1 for non-intersection patches. `) P# K! T. R8 f3 y! e* |' i% d
auto? ;; whether or not this intersection will switch automatically.* L+ d5 M1 X/ y) l3 j+ }
;; false for non-intersection patches.7 f9 N7 P- W' @2 ~" P. K' y
]
: i9 w; C* D9 g: X% N& a
. p% ]0 {: C( `7 ?( d
/ ^& y' \( s+ p; D Q# E- ]6 @8 \;;;;;;;;;;;;;;;;;;;;;;
5 V5 D4 Y1 p P; Z;; Setup Procedures ;;: D1 I& C# Z. Y2 n0 q- ]5 c( `
;;;;;;;;;;;;;;;;;;;;;;
" a7 A$ G$ @4 V8 d
' T. @8 Q- z7 T' n;; Initialize the display by giving the global and patch variables initial values.0 N* e1 C! A7 Q0 [* L* I' M7 r* M
;; Create num-cars of turtles if there are enough road patches for one turtle to
) d* k7 I$ B; c7 K( @- h/ b/ Y- r;; be created per road patch. Set up the plots.+ ^4 t% M: M C
to setup2 g' Z1 u, w3 Z$ L3 J
ca% M7 I( j) r1 X' u
setup-globals
; [7 O" ~5 x/ Y4 Y' [
* D* o$ g' r" y3 a* X' h ;; First we ask the patches to draw themselves and set up a few variables( K) M I4 S; C7 F- N
setup-patches8 g" |1 F* D9 `9 C
make-current one-of intersections
& d3 V0 S5 }- A, \ label-current$ A% Z7 U. I" I- C. m! s$ w
, P( ~5 ~9 B3 `# J$ J- ~8 Z" A
set-default-shape turtles "car"% j0 l# {: U( ^- m2 B
) X; G" g& C- Z/ S4 q# ?0 W" [
if (num-cars > count roads)
- h, a. F0 g* X, |: x; N# u; E [! p4 C3 b; ]4 c# E, n" L
user-message (word "There are too many cars for the amount of "
5 N4 b- C( A% C( ^7 R2 J! @ "road. Either increase the amount of roads " x8 l3 J9 b3 V$ X0 O
"by increasing the GRID-SIZE-X or ": h0 T% f8 A" k4 `6 b
"GRID-SIZE-Y sliders, or decrease the "
8 @- K$ A+ P! Y "number of cars by lowering the NUMBER slider.\n"4 ?; V& o* s" P! z
"The setup has stopped.")$ k( K# c( e8 S) W
stop
9 L+ s- w6 ~% d' C( s+ L: o ]) w/ `) U' Q$ X, h; U7 h! z0 M
" w8 N7 n; W8 K6 Q9 q/ d- B: Y
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color- P# j9 f5 ~4 T: Z! V6 w
crt num-cars8 \/ j) l- e% o7 E
[
) @ a8 g" @. T s% S* ? setup-cars
3 S( ]; D- t; ?% N! z) a set-car-color
3 D7 ~- N M4 a) B record-data
( K: \) }- Q; p; y* l; d% }1 m) N; h ]
; h" c0 c! z# e( r- \$ U6 z8 z; F0 b
9 O. x5 K7 a7 j4 x6 ]# V! F: M ;; give the turtles an initial speed; J1 _: A& K9 E; o9 u0 |$ V7 E, M
ask turtles [ set-car-speed ]
% |1 B" \, V8 O; T% C
# V& ~! u" e8 p2 j. I reset-ticks" E3 w- C; O+ F& r) {6 E
end! G+ f9 w) o- l9 C+ U" z; x5 j4 w6 J
2 W4 j! H+ d' Z, z: I } L;; Initialize the global variables to appropriate values# L2 ?9 @/ R& q" c$ A3 W
to setup-globals
8 X( K8 x, z3 Z( C) L8 I set current-light nobody ;; just for now, since there are no lights yet/ T( \" g1 I. v
set phase 0
6 K. U$ C/ M( U6 @" [ set num-cars-stopped 03 A$ F0 `6 M$ o! n, {3 H: M
set grid-x-inc world-width / grid-size-x
; M! v% Y2 ^7 t. E v set grid-y-inc world-height / grid-size-y# f0 G- E, Q* u1 v0 S7 v
! y; B% Y! m2 s; o- w& d( h
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary" J) g1 x( y) ]+ F" ]' N
set acceleration 0.099
0 I% f) `8 `7 I( ~" v1 _' eend
. _ k+ e6 G7 T
- w3 C n' X) x;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
; v: L5 ^ v/ f- W" l;; and initialize the traffic lights to one setting0 S0 B6 R. U ?! Z9 @
to setup-patches; M' k ] P) ?- ]
;; initialize the patch-owned variables and color the patches to a base-color5 j d: k) J; j4 z7 f2 }. e+ p
ask patches4 i9 s+ w& s' f2 |( p) v+ I
[4 g- E6 q0 t% ?
set intersection? false
) `9 i- F4 Y) \+ T3 C( S set auto? false! O5 M2 \4 E2 p; ^2 b
set green-light-up? true7 V: E3 A& I6 l, B6 {
set my-row -15 ~# o* G1 N5 F
set my-column -1
1 R; K# o0 W( H3 X/ m set my-phase -1
9 \$ R2 `( H3 i set pcolor brown + 30 a# U/ O* ]2 Q/ \. W1 ?; P
]3 T7 l: d R5 C" S
) C! T6 |- I& T: U, Q9 F J! V8 i ;; initialize the global variables that hold patch agentsets% S8 e3 @+ \- ?5 @% l
set roads patches with# s$ [8 ?5 D- }
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 o1 ]) b' \7 V, X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 ]' {- C$ E( b! f set intersections roads with
5 W2 F- [0 x) S, {% g [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
0 f9 K3 w5 m3 J9 j( t2 u! ~ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
+ P: H% a c3 V, h5 A/ x* u& C D2 o
ask roads [ set pcolor white ]8 t5 m: P# P' a* ?
setup-intersections. ~% ~7 C% }& B% B
end( K! _! v+ ~0 L2 z/ ]$ p
其中定义道路的句子,如下所示,是什么意思啊?0 Q0 a$ f0 C1 i$ S) ^
set roads patches with7 d$ l# h: _# L* G2 o+ r8 g
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ f+ w2 a( C/ \7 T2 ?5 O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 f( ^3 W9 u, v2 O. I1 A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? |
|