|
|
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。
9 D$ i {2 a9 }. g8 nnetlogo自带的social science--traffic grid这一例子当中,
2 Y3 e, C3 f, ~* l6 iglobals
5 G5 J" t3 n! `4 [; w: e[1 N0 M5 ?9 p+ I& z! Q
grid-x-inc ;; the amount of patches in between two roads in the x direction
$ u5 R5 w' z& s7 m6 j grid-y-inc ;; the amount of patches in between two roads in the y direction* u7 k* S+ B3 e1 X: B/ ?
acceleration ;; the constant that controls how much a car speeds up or slows down by if2 ~8 Q1 o0 ~8 W" ~; s4 d
;; it is to accelerate or decelerate
. B; F8 q5 g7 f& t" b# q3 ]) @ phase ;; keeps track of the phase
0 f! M! Q3 m5 C num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
$ o6 Y% F2 d' j( F/ S5 E current-light ;; the currently selected light( Y# S' f) c) _+ ^5 x, p
& E& \' [* M& w4 y, |; v
;; patch agentsets
5 B% S) k4 ?, w- m& r' V9 }$ G intersections ;; agentset containing the patches that are intersections
/ E$ ]' D1 l9 t- P% P roads ;; agentset containing the patches that are roads
' L+ U7 n+ d1 k: h P8 K, w+ U]
" o; A5 I! b4 X! b) Y
, j9 [; `4 b3 Bturtles-own
* ]; S x, ~8 G. S& T9 ~! l# U[5 h% X, q& E- m$ q% Q5 g U8 y. @4 A
speed ;; the speed of the turtle! N2 c8 w9 y+ b5 E* X
up-car? ;; true if the turtle moves downwards and false if it moves to the right
' t3 f. `( {2 M& t- U) f* ]( O wait-time ;; the amount of time since the last time a turtle has moved
# T- s4 V3 c( S8 ]8 E]( e* K+ s! S. |: f' b
% n& P. l$ D ^6 D7 w, X
patches-own" _* R+ U m. g! g. U6 K
[7 A% x( j" I% R& o" [5 R5 U
intersection? ;; true if the patch is at the intersection of two roads" P, |3 r5 y& D5 B
green-light-up? ;; true if the green light is above the intersection. otherwise, false.* \' J% ~: d2 f( c
;; false for a non-intersection patches.8 C- z Y6 v! ]( j
my-row ;; the row of the intersection counting from the upper left corner of the
9 V& ~) w5 _! \5 `7 `: C: L ;; world. -1 for non-intersection patches.
7 U: ]; H: {" a* b* G my-column ;; the column of the intersection counting from the upper left corner of the' y6 V6 N& ?1 }# ~- V8 \' O1 X
;; world. -1 for non-intersection patches." M: [4 {1 x- ?: j) v2 a
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
* D5 W% |) l% G) \( a# V auto? ;; whether or not this intersection will switch automatically.
/ u8 i' J- `( ]" v, B. A ;; false for non-intersection patches.
- R9 F, Y3 G# J4 Q* o, j) q# T]: `2 d/ b& ~6 N' ?, e z. }% Q( ^
W4 @4 f. X, i# G% M+ H' B( v/ ?; i& ^+ T+ S
;;;;;;;;;;;;;;;;;;;;;;
4 Y9 d5 N5 ^2 y, V F;; Setup Procedures ;;
; P& x2 D; _/ }5 L7 V5 f( y/ j;;;;;;;;;;;;;;;;;;;;;;
' N) d: P% G3 K, X0 v" T& s" r4 T1 d$ x2 d; K) c4 N, J1 _
;; Initialize the display by giving the global and patch variables initial values.
% e2 P+ ]( U& E+ o;; Create num-cars of turtles if there are enough road patches for one turtle to
- e8 d9 h5 ^. R) S# i' i8 i;; be created per road patch. Set up the plots.- h, @5 `2 `8 Z" x; R0 P' Z
to setup' t" k/ V2 X4 {, m3 q' k
ca5 a) T) D- p& i4 O+ V% }
setup-globals
$ F: m/ ]' t8 M0 H) h7 h: h7 U8 ~6 A
;; First we ask the patches to draw themselves and set up a few variables
3 B$ v/ e* F2 u5 N' z0 a setup-patches
! {! x, L; q: g( @+ M* |. o: q make-current one-of intersections3 w3 [% `! Z4 u
label-current
/ Z) x J$ ^( c& t
- Y; h, _2 } r; R set-default-shape turtles "car"; q2 T- @* o8 Y
; t) l! l$ x# e6 t* h" j: l7 e5 P: |
if (num-cars > count roads)
; e: W# P3 f F7 k [, E+ G2 T1 x: Q) x3 Y" {8 f. `
user-message (word "There are too many cars for the amount of "4 V* ?( k$ _3 g3 l
"road. Either increase the amount of roads "* n9 y! Q+ _ u2 V
"by increasing the GRID-SIZE-X or "3 o5 v! b5 G. U `7 G% i+ E
"GRID-SIZE-Y sliders, or decrease the "
$ r. y% N( ]# G$ c6 Z# r "number of cars by lowering the NUMBER slider.\n"* Y% d, c' L$ I# f3 H
"The setup has stopped.")
0 Q i% P. j, w# x, ^) \ stop
0 p% X1 s& I1 B2 H$ y8 Q ]4 z! M1 v @$ `' h: A9 V* L
; e0 U0 t3 j: S- i7 o
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color" ?7 s+ n; A- \& C6 g4 n
crt num-cars
0 O! r! Z1 x1 C [
0 { w$ Z# `* [* K$ y5 O setup-cars2 u: K" {$ ^9 E/ d8 }3 ]- _
set-car-color
, R* T) l& O" x4 W record-data0 S+ V" T+ v. z7 V5 o0 r; P4 P
]
1 }! s) C3 M7 M5 ~+ n
/ E s+ i. u- w: ~ I( R ;; give the turtles an initial speed1 u. U9 ]- s, y0 k# `& t! o
ask turtles [ set-car-speed ]) K- { y4 m1 k- ~: d7 m4 _
0 V5 S: c- f+ G
reset-ticks
7 F2 ^; a4 J) y2 Send- M% E8 z k0 n
r9 G9 f2 l8 C8 ]# Z$ X. y8 }
;; Initialize the global variables to appropriate values" K* f4 |6 ?4 [& L
to setup-globals5 k9 {; b% E4 H( P+ Q
set current-light nobody ;; just for now, since there are no lights yet
! h: g) I F- x0 C X6 A/ t0 R set phase 0# ^+ f7 @4 y3 g8 O5 L: s2 q
set num-cars-stopped 0
: z" K0 S- w6 F set grid-x-inc world-width / grid-size-x. b' r: |! o6 F& P5 C1 @. n
set grid-y-inc world-height / grid-size-y
# I! J A0 ?' `2 a% R# A7 F2 F8 t3 a: |! y" m' J9 K
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
w1 P- T, u% I; ?, N9 f) k: { set acceleration 0.099
- p3 q1 |9 [% ?8 T0 q6 wend: |: W) u# W, L$ [
- x5 i9 p( H2 D1 _1 f0 X) Q6 G/ Q;; Make the patches have appropriate colors, set up the roads and intersections agentsets,% W+ o, I! S+ n) \$ q& l7 x' j
;; and initialize the traffic lights to one setting
* Z e! w8 X: I8 @to setup-patches3 B4 ]' i3 m: r8 a; o2 H8 t- m0 i3 E
;; initialize the patch-owned variables and color the patches to a base-color
$ M4 ^ ]! j( w% h ask patches. @( X3 C$ R* ~1 e' s
[
* L. a) ?" a x0 k, h2 r6 ? set intersection? false
$ T2 K# ~& ?2 }( @ set auto? false
- u- c" V4 L: r7 }- B' t( f set green-light-up? true
; b' D! Z8 e0 ?) p% S1 H6 D" M Y7 \ set my-row -1+ j0 |. Q9 V: ~' ]* B$ Q
set my-column -1/ ^+ F/ p: [+ w# b! j, f
set my-phase -1
9 D* L- a# y" M! G" Q% D; A set pcolor brown + 3* z& N" I' T0 d
]9 U$ r! o3 {' Z( b! i) h9 u
) y) m* w$ J6 H5 {0 I) d. g ;; initialize the global variables that hold patch agentsets
+ ]: [& _7 N/ {/ Z! f2 h* B set roads patches with
4 i+ Q) {- U$ H3 c0 U [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& T, d. @ z# s; @. G: t" R$ O1 _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
* z4 B7 F9 t6 W set intersections roads with( m6 B/ U; S8 r& F. ?
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and" n+ ^( |0 h, d* i! J8 M9 V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 y6 V/ q! I4 d! A
, c, d% m3 a* u ask roads [ set pcolor white ]3 g1 o% ?; M m/ U- f: C" g
setup-intersections0 a: q# Y' u# Z! U
end& e, Z# H) {; V2 _: @# F: S! w7 t/ ^# n
其中定义道路的句子,如下所示,是什么意思啊?8 U1 a* ~/ R" |
set roads patches with( Q9 J$ d; @/ Q y3 P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: t! }5 Y; s5 J0 b/ @
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]' N" j d- `$ t6 I, e
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? |
|