|
|
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。
. U+ a+ R8 K( [" Fnetlogo自带的social science--traffic grid这一例子当中,' Q$ \! \% F7 g9 @; q& G% {. P
globals
3 l8 _% A& y F/ H; Q! T% g! L[! t$ U7 b+ p' H* X
grid-x-inc ;; the amount of patches in between two roads in the x direction. M! n! b+ o- N, z# K% ]
grid-y-inc ;; the amount of patches in between two roads in the y direction
" R' O. K0 W, s acceleration ;; the constant that controls how much a car speeds up or slows down by if
/ o1 K! `* I( b7 w0 _! X& l ;; it is to accelerate or decelerate
% L- O. p2 ` _2 M8 W phase ;; keeps track of the phase8 Q# T: g8 s: N, X% w7 J4 K
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure4 V7 x q; `9 Z4 F
current-light ;; the currently selected light( Q5 B u+ d C$ S; V) {( F5 w
) W/ a( x2 j0 o' m7 |
;; patch agentsets
4 M' s) D# A8 F! S intersections ;; agentset containing the patches that are intersections$ r) ]9 T1 B6 Q$ k0 V/ F. W
roads ;; agentset containing the patches that are roads
. l F$ M8 _ r! s* X, i]
5 A7 |# y ^0 H) [- \' E; L
9 R$ u7 {( Y" h$ yturtles-own9 U9 w: R' V- C: o) u! L
[) z. J! c/ t. r, y% q
speed ;; the speed of the turtle: S4 q, n; i7 i7 u
up-car? ;; true if the turtle moves downwards and false if it moves to the right
/ }) f- U4 l& _: A wait-time ;; the amount of time since the last time a turtle has moved
* z0 J* Z: O7 c& l/ a]# ~0 `! _9 T a" J; m1 V
; F1 z: _7 c/ K \/ X# w+ C8 b7 Z
patches-own# C5 Q( F9 I8 U z# Q9 p
[* @) z }/ u6 A" T1 p
intersection? ;; true if the patch is at the intersection of two roads/ w+ m9 }9 b! l( w- u+ N% S+ V
green-light-up? ;; true if the green light is above the intersection. otherwise, false., f3 H: E( W6 l& c# V
;; false for a non-intersection patches.
# J. Z& R$ S' b" s; f; h my-row ;; the row of the intersection counting from the upper left corner of the
' U$ E1 e, b9 I5 V [; d ;; world. -1 for non-intersection patches.
9 ~9 S2 h2 Q7 F5 U8 V: R' m my-column ;; the column of the intersection counting from the upper left corner of the
/ W+ d1 W2 d8 q! G5 f ;; world. -1 for non-intersection patches.
* v# ~4 E( m; V+ ]3 D: a# t5 ` my-phase ;; the phase for the intersection. -1 for non-intersection patches.+ G: L( {$ c0 x' \* Z( A
auto? ;; whether or not this intersection will switch automatically.) M9 u0 O$ h+ M; u
;; false for non-intersection patches.
" e; t8 ]( J& K& P. r. W0 Q L& r]$ v# o7 E. b# X+ E! ]* z5 X* A# w
# v% Z- `9 | w( x. |
) `& e1 B3 e: E;;;;;;;;;;;;;;;;;;;;;; @* w: {2 r3 f
;; Setup Procedures ;;! e# |) f" U6 z4 S5 H& I
;;;;;;;;;;;;;;;;;;;;;;
9 T0 w, j/ j6 Y2 A: e( c, |7 \3 m8 i* a
;; Initialize the display by giving the global and patch variables initial values.
' @! W( @. A$ K! m;; Create num-cars of turtles if there are enough road patches for one turtle to2 t( b' d; B3 U
;; be created per road patch. Set up the plots.% E5 x! M& }( {4 y6 g& ~
to setup
% T w1 J# S: ]! q. S5 R4 o2 f+ b ca
, X) h U' f5 [6 b6 p+ g+ ?. } setup-globals
, G6 d3 k4 t% p- d
" M$ N8 r8 P0 i ;; First we ask the patches to draw themselves and set up a few variables r' t/ ]! |/ y& h: N
setup-patches
5 b2 \- G5 r1 R* G make-current one-of intersections; ?& O$ g+ k Q. j7 v' n/ ~7 s5 f
label-current+ B4 {, h' q" Q9 ^' h2 ~! a
/ W; `1 a. t* A% W5 R3 P
set-default-shape turtles "car"
% _; G$ {1 Z, G) v2 Y, m9 u& H: t. n" b9 r4 L+ [, ~8 q2 h& z
if (num-cars > count roads)$ m( s& A$ `6 Z: F# |/ C6 x
[' G5 n* I: h. S, o5 K& o* ^5 X
user-message (word "There are too many cars for the amount of "
9 Q2 Z; S2 @6 q* J; R z' j( f, ` "road. Either increase the amount of roads "; U) y2 K! o4 M( }
"by increasing the GRID-SIZE-X or "
. t3 z; M9 d7 k. ]* S" S. v "GRID-SIZE-Y sliders, or decrease the "7 J+ r; U z* B. @3 s6 \4 z
"number of cars by lowering the NUMBER slider.\n"
( a" ?6 x2 I% ? "The setup has stopped.")
' c0 F; o3 u7 y$ R/ g% i1 V. B stop
/ c: p* F# c7 G% {. @. G ]
7 f6 j+ Y4 v3 w+ ?- ^; g
: V v4 y' }( R" g, | ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
3 ^7 a- a! ?' d" l& t( U crt num-cars
0 }# u' y: P0 \! W [
! }9 \5 v+ G1 g4 |$ y& w setup-cars$ B' p) j& J( i7 g- g( g
set-car-color
1 h$ F- r6 t- w/ R8 \1 |0 c record-data. g2 K% \& [9 t# s% s) b
]
5 h4 h* k" {) B, N$ Q' e( k
+ b' ^ ?$ x# Z/ r+ m/ E ;; give the turtles an initial speed$ _) O" |, [% d" v: g: T
ask turtles [ set-car-speed ]# m } \; z" W8 P
/ G( X# A: v/ ?- b# K reset-ticks
' Y% c4 O: t# T0 K# N6 t3 S6 Kend
$ \" X3 U1 V. G( Z2 C, T# r# W# S! i( q) G( K. n# B
;; Initialize the global variables to appropriate values" v; d2 l3 C7 J) Q* m# y% E1 t
to setup-globals
3 ?. t( R+ v3 R4 N! X+ r( u set current-light nobody ;; just for now, since there are no lights yet" y3 \' W- v; `4 K
set phase 0
+ a4 ]/ H+ K) ~+ F set num-cars-stopped 0
" @, Q: M) ]5 p% E8 {. A# R# j set grid-x-inc world-width / grid-size-x, Q$ p B H0 U: F" ?# l; b8 @9 \
set grid-y-inc world-height / grid-size-y
t2 H7 Y, u3 H8 G+ {
/ W! f/ U% f6 z" Z4 H) V8 I ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: S7 x# U* P# ~
set acceleration 0.099 B/ W! ?6 W( _9 V! T1 y
end F3 n9 {* ]* Z W& b! p6 a/ h. M* P
( Q! q6 W$ j+ T* w* z;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 t3 V" M* k% x7 A! \3 Z$ N2 C+ o
;; and initialize the traffic lights to one setting1 e; Y, x6 O9 }: s6 h
to setup-patches
( ]! e/ U* k) o( O$ g% J ;; initialize the patch-owned variables and color the patches to a base-color
" {* V$ s; ]! B; o6 p ask patches
- z; j% R5 s& S* J/ o( h% I [
$ s8 M) t! N8 g+ h& c- G set intersection? false
& h, @% K& J6 o set auto? false/ Q' T' [" M( V% O4 s
set green-light-up? true! Z. c. c* L$ v0 {9 p4 |- e# t
set my-row -1; s2 m9 ^3 }% U2 L7 h0 `. e F
set my-column -13 Q% E( k, I) i& _1 g
set my-phase -1 n$ f* g; C" U9 g, S/ t
set pcolor brown + 3+ ~4 Z) T/ E1 G' B/ p
]# J4 E. M6 `) c
9 p* I1 i$ \. W: ~2 c. Y
;; initialize the global variables that hold patch agentsets/ t s% G- R& B4 Z. x
set roads patches with! c8 C- T: ]0 Y9 k" H
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% R% O; J$ i" O1 L" }. ?( T# c
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]; \* @, h; b4 b e
set intersections roads with, e# c1 j7 @3 y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
6 K- f1 w6 E3 b' t9 d. T (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( L7 }- p: c, I
1 p2 F, \" z, w& P6 a ask roads [ set pcolor white ]0 g/ ?9 w8 W. j, l/ F3 I! P! {& D
setup-intersections
# L- S' V K) v- G- ` C$ Yend: r; q+ J) B9 k4 q7 E$ j
其中定义道路的句子,如下所示,是什么意思啊?
$ |% B2 J- m2 R' W5 n/ v0 d/ ?5 h set roads patches with
, \5 y5 q( T3 T6 u0 l [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 W" `: m3 X; b) `4 j- y" _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. ^; g. Z$ a5 m5 L; [! S, Y8 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? |
|