|
|
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。" X) t/ V3 d+ l' M
netlogo自带的social science--traffic grid这一例子当中,
; A+ T( |- _5 \6 H5 [; ]( A$ c0 o3 cglobals
3 O8 D/ r5 b# @. N[! c b4 O, h2 W' w7 [
grid-x-inc ;; the amount of patches in between two roads in the x direction) i! U8 H" x6 X% r/ j& W
grid-y-inc ;; the amount of patches in between two roads in the y direction
0 G& R& i6 {/ p& h" M1 S acceleration ;; the constant that controls how much a car speeds up or slows down by if
- N; f6 S/ G1 v6 r) n ;; it is to accelerate or decelerate
& ?% A5 O( w+ q* g2 W phase ;; keeps track of the phase
' H2 w. j1 w1 l; a0 T. T; m num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
6 b) j/ Q3 k2 _7 a current-light ;; the currently selected light
6 ^- Y9 q' S) I+ z( G% j8 _/ S& l) c |) X
;; patch agentsets
" q7 T }6 J$ A/ A5 V7 A- J intersections ;; agentset containing the patches that are intersections
( o2 K4 Q7 j* k# ]; [* [ roads ;; agentset containing the patches that are roads$ N1 @7 s. \: r& O) P4 U) T
]
' ?5 {3 Q9 R( N
1 \# B8 r, t9 \) w' b+ x7 Jturtles-own: h ?& _! S& `- C% B' E( \
[
# ~+ \) F6 s: o9 o c speed ;; the speed of the turtle" H" a( V2 e( \4 y8 @& h
up-car? ;; true if the turtle moves downwards and false if it moves to the right- I+ F# @( {2 s* ?. b5 `
wait-time ;; the amount of time since the last time a turtle has moved- ~8 | s$ I: x* L* C S
]/ n1 v. a M' Y5 x4 N& t" \
- G2 H6 d1 e/ ?! Wpatches-own( n# R7 q& T, A. w0 J* b0 W
[
3 Z, E3 n1 z) G intersection? ;; true if the patch is at the intersection of two roads" u. B0 |4 K; e8 w+ z8 T8 f
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
: }/ X$ i a: E6 x8 _' | ;; false for a non-intersection patches.1 y; s% d- ~2 e2 ^
my-row ;; the row of the intersection counting from the upper left corner of the$ y( Q( v* T0 b+ C: {/ O, ?# B
;; world. -1 for non-intersection patches.
" N& R2 e+ d8 @3 @, A$ D my-column ;; the column of the intersection counting from the upper left corner of the
- R! T! a6 M2 P5 m1 H/ | ;; world. -1 for non-intersection patches.8 a6 Y; @; C5 h& Z B2 S0 x
my-phase ;; the phase for the intersection. -1 for non-intersection patches.* f& ?+ J7 g* a0 y( [
auto? ;; whether or not this intersection will switch automatically.# H7 d1 k# t9 I% y
;; false for non-intersection patches.
6 `& x0 Y: h) J, t]
& Y* q8 C+ f5 k6 b: K- p L, w( F& d3 F- d. M; B
4 @# u/ w! b7 q# }% J2 F;;;;;;;;;;;;;;;;;;;;;;
8 d' K5 e K# o R) S; O% {;; Setup Procedures ;;
9 N" Z: T4 ]* N- S5 f;;;;;;;;;;;;;;;;;;;;;;! K. w. @: [6 d- r" [+ M
; k+ A5 g& Y1 O;; Initialize the display by giving the global and patch variables initial values.& S1 j! H) l m0 x: d1 l; U' _9 Z0 f
;; Create num-cars of turtles if there are enough road patches for one turtle to
' }9 \; L" o n/ D3 B- G+ e) l% O;; be created per road patch. Set up the plots.
1 I/ [; { y8 e5 U8 u1 oto setup
; m! V6 |6 t3 Q: i2 x, \ ca
/ M9 X- ?% c% n9 a. \ setup-globals5 B v; k' o0 q: p/ h" S( S6 t* V
0 N& e Q3 k% h" \* _ ;; First we ask the patches to draw themselves and set up a few variables
; R1 P# C6 L& z2 z+ R setup-patches
% Z2 P! q m$ y5 W7 c make-current one-of intersections. K0 s' ]* M& O' r; M) F4 b: |0 f% B
label-current
, e' s8 C& j6 M0 a* O3 W
5 K0 T. K5 x: H/ Q. [ set-default-shape turtles "car"5 g+ t' c8 I3 w U+ n* }0 S
/ Z0 q7 g- I- k1 g if (num-cars > count roads)
/ K/ R6 c" S# }& q9 ?3 T# N [
1 F4 i5 O' {: Z6 ?7 t1 g/ k8 n user-message (word "There are too many cars for the amount of "5 W' ^ Y( A/ M; G% f, S
"road. Either increase the amount of roads "+ I3 k% L7 Q, S# n
"by increasing the GRID-SIZE-X or "; v% `& q8 ]* b+ A" y6 {
"GRID-SIZE-Y sliders, or decrease the "6 Z, v' r7 ?- p1 m4 p- j/ Y
"number of cars by lowering the NUMBER slider.\n". D! Y! J7 t8 M) {
"The setup has stopped.")- G' O) x9 o5 R9 `
stop
9 f/ ^7 ^. W. q. r ]# `- \( x6 W) O* o- g
9 H$ c0 W2 G% H' o7 r) a8 @
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 v) F# P( h7 {: ?$ }) F crt num-cars# b8 h8 X; q3 ?
[( N4 P$ o# m1 G) C0 }
setup-cars
; Y6 O- Y# ]- D! | W set-car-color
% J" i* w$ [4 m0 o; w/ \ l! a record-data
5 Y9 g8 E% G- M( C5 p0 ` ]
! K5 g8 |' R& A* [
& t8 r$ `$ K, S, m6 n ;; give the turtles an initial speed' x- Q: F4 @+ D8 x
ask turtles [ set-car-speed ]2 F9 w3 w$ F, b% m7 [. `/ }. X8 c
8 n5 O7 [7 T0 F+ r a$ X- c- y
reset-ticks
) o) ~ s6 j! H' C0 X o$ i( t" Oend+ p( e. P9 M' h5 x
& Q& h0 \* K7 M;; Initialize the global variables to appropriate values7 s4 Z/ }+ ~0 k. J
to setup-globals
$ C& w1 F- q. c) x* }- k set current-light nobody ;; just for now, since there are no lights yet& P0 |8 Z% ?1 V9 f+ T# d
set phase 08 t3 l3 }0 L% F. j+ t8 C9 k
set num-cars-stopped 0
- r; {/ u# a! E3 J# M% o) Y% N( H set grid-x-inc world-width / grid-size-x! w5 r2 C9 q" y" I
set grid-y-inc world-height / grid-size-y# j" M9 ]% W' [- k$ j2 Z
* P9 T# h% ~0 x6 g' i1 w A
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
! W) k2 W0 G7 } set acceleration 0.099. ]$ }* K# }- J
end( j0 c3 \3 e1 n
; S N: i' b! C8 B
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,. A9 ~( I9 n9 @& }4 Y" d8 b8 L3 W
;; and initialize the traffic lights to one setting
8 Q0 K" _( S: ?* ]2 O( @" t7 u. ~to setup-patches
' l% O0 w( \+ A. I* v4 ~$ _9 s ;; initialize the patch-owned variables and color the patches to a base-color n" j M, B) A0 d! y% |
ask patches
: Z0 L4 p) s* h a$ s- i6 U3 N [& [. {1 g& B- q1 Z7 K U9 r
set intersection? false* y/ Z* N! S, u- e
set auto? false( x- S+ u$ j& D, _# |- i4 g/ X W
set green-light-up? true
8 J$ {9 w- E) r: H2 V set my-row -1
8 M* A9 ?3 ~6 f# ^ set my-column -15 o) W/ `4 c) p: V0 G0 w4 Z
set my-phase -14 |5 c) A8 |! c: j' S
set pcolor brown + 3
6 G& Y% v4 c5 ? ]: m& \9 m3 e6 X1 d. g& V3 }# F' w
" r$ u9 x# N; S5 O' O ;; initialize the global variables that hold patch agentsets
# c( w+ A* B, _# R; D set roads patches with+ r, L* t* _# ^/ a4 Q' N6 c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- Z8 Z( c5 C( `- s4 Y2 Q. y; K) ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 H8 M) K# S' B# i$ h+ } set intersections roads with
* K' I" N/ _! a, E1 S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
/ R0 |' R& P. s. c$ p# [4 v (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; r2 k L. ?9 x" a
( R j8 S) [, F _: a ask roads [ set pcolor white ]
6 ^1 A( k, W) _, }+ n1 v+ z setup-intersections
3 L: a6 b }# d, Wend
% L! `2 z) M+ W' ^. p* K其中定义道路的句子,如下所示,是什么意思啊?
7 u& C4 i4 A. w5 M8 G set roads patches with: B8 Y' D1 W) h ?5 T1 D: @4 |: x
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
# V( ^$ W8 { f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 C$ x; t( }, M- v1 T
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? |
|