|
|
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。1 g9 E, [9 F' R! p7 z2 U
netlogo自带的social science--traffic grid这一例子当中,4 M! i* G0 ~. E
globals
6 w9 ` H9 h9 i9 a3 C# k% C! O: }[
8 d: }1 X* U, R: l, o grid-x-inc ;; the amount of patches in between two roads in the x direction9 E3 M9 {6 w+ C. A9 ~& I" X
grid-y-inc ;; the amount of patches in between two roads in the y direction3 T. s8 Q% Z4 L8 S* O
acceleration ;; the constant that controls how much a car speeds up or slows down by if1 C; Z" o% K2 x! F& Q3 W) n
;; it is to accelerate or decelerate
* f& j; i, L7 E- L9 } phase ;; keeps track of the phase
" g. F5 v* J1 {& k4 T num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure. B w! M3 o% x: N6 r1 b
current-light ;; the currently selected light
5 h; `4 X! E' ]3 w" b2 V' z- [* y& g3 B. }6 m+ a
;; patch agentsets( m% F9 N, z8 [3 @- Z. }
intersections ;; agentset containing the patches that are intersections
$ h# k* a3 Q# O1 v, x% ` roads ;; agentset containing the patches that are roads
; Q3 o" ]# B6 O: P! d1 []
2 ^. }4 H6 J! A U' o0 g7 z) P% _& j/ H" z, _6 w
turtles-own. W1 Q$ T$ t* o* r: }, }2 r
[
, ~+ e- m( w9 ]( B( h/ M speed ;; the speed of the turtle
9 l9 F8 R; t8 p up-car? ;; true if the turtle moves downwards and false if it moves to the right! _% X. ?' Q( K s. }( R) O
wait-time ;; the amount of time since the last time a turtle has moved- e$ {0 S3 z, A; A
]6 @" M8 F. T% U7 V. O( ?
, z* L2 n6 X9 V6 j1 A0 I/ z' \/ l
patches-own; ? N5 P: h- ^& F0 T7 j- q/ U9 J
[) T! i5 v& i; r
intersection? ;; true if the patch is at the intersection of two roads
; T) ~* Z/ \1 \. y$ X) c/ X green-light-up? ;; true if the green light is above the intersection. otherwise, false.
" F! {: v9 j6 x; Y ;; false for a non-intersection patches." l$ r' x& c8 `( f4 ~* B& D$ Q3 q
my-row ;; the row of the intersection counting from the upper left corner of the1 u n' z% k* i1 J
;; world. -1 for non-intersection patches.2 ^! T+ u) u7 p! S- C6 g
my-column ;; the column of the intersection counting from the upper left corner of the
) t4 V7 P m3 z ;; world. -1 for non-intersection patches.
7 w2 R3 w5 T& F# u) ?0 j; Y my-phase ;; the phase for the intersection. -1 for non-intersection patches.
+ X2 K* K# S( M+ q auto? ;; whether or not this intersection will switch automatically.
" z8 |* b- x. Z2 V! g c! u ;; false for non-intersection patches.2 I% l2 L# h; B6 A$ k: W
]
9 Q1 q- i4 V7 o
4 e8 n; F6 }1 ^. D+ D8 k! X9 y' Z8 h5 N$ M b' Q* z& y2 E6 C
;;;;;;;;;;;;;;;;;;;;;;6 Z' { m- P" }( v9 n+ G
;; Setup Procedures ;;
8 |* ^$ m5 t8 T8 R/ g;;;;;;;;;;;;;;;;;;;;;;8 q3 l1 M5 o- F$ H
$ Z1 Y/ U Z( t6 S% l% g
;; Initialize the display by giving the global and patch variables initial values.
) K$ W( Q7 R+ k+ Y' V, F;; Create num-cars of turtles if there are enough road patches for one turtle to
. N9 h0 | u9 O$ |9 i1 L X: y;; be created per road patch. Set up the plots.9 M2 E, e0 m" b
to setup) k. V* S- S4 [! o8 v
ca
8 B) }* U0 S9 n1 B, a4 o% }) Y setup-globals
! U+ ?+ {0 k6 u3 V, j: G- h% |5 D/ i/ X2 i
;; First we ask the patches to draw themselves and set up a few variables& \6 L( d+ S1 v k
setup-patches7 v2 |( L" R5 t- P/ P
make-current one-of intersections
, [; I0 e7 ]8 V. p2 s1 a label-current; O6 T4 d" g! c% D
/ H! b4 z7 `3 Q9 E' Z# l4 w" l set-default-shape turtles "car"
: f7 A( I8 G. ^$ o
; u8 {$ E1 ^# J. z% M2 ^3 D" g if (num-cars > count roads) t; S: W" s: Q. D7 y# c
[; b% S' r2 S3 \1 i
user-message (word "There are too many cars for the amount of "8 \* Q+ B3 `4 N/ z4 P6 h8 |
"road. Either increase the amount of roads "3 L( M% l: o3 A; g2 R2 Y
"by increasing the GRID-SIZE-X or "* P1 o+ C6 s8 W/ S3 o8 D3 b
"GRID-SIZE-Y sliders, or decrease the "
( e0 U6 w0 b) o "number of cars by lowering the NUMBER slider.\n"
* x2 v) X) Y, ?5 ]/ R "The setup has stopped.")
0 u0 E6 B* S. c9 S stop, R8 D/ R" U1 R
]
& H* j9 L1 P' g* Z, q
2 x9 @9 B9 C! _8 u" _% ]; [ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color1 b9 k/ ?7 l5 b% |
crt num-cars/ ?8 R0 m; Z$ o+ `" n F! l2 k
[8 K$ I) R0 R& t; }: R8 V. C
setup-cars
( Y% Y! R+ v7 n$ H2 l6 C set-car-color& k5 b% A3 i+ P" ~4 p, i
record-data; w, m# `- Q8 F0 a( B$ G9 u
], _1 W. `9 k3 @- Y2 w1 ?- ~
2 ]' B+ ~" y/ t5 H- t7 t ;; give the turtles an initial speed
' G7 G0 |; ?- V. f ask turtles [ set-car-speed ]
( K2 W7 [, c w2 u
6 j2 ~2 p: j( P/ R reset-ticks% B% P0 t% ?* g" [5 ^; T
end
$ `+ N: V5 s7 w* [. \# b( V2 I( z( \
;; Initialize the global variables to appropriate values, E5 t" ~7 n# ^0 ]
to setup-globals
" s0 P, w) f; E6 A/ n5 @ set current-light nobody ;; just for now, since there are no lights yet
H E0 t& F; K: I; N set phase 0
: n& m1 }$ [ g- l: Q# s set num-cars-stopped 0' \* y( k2 W2 R d2 _$ s
set grid-x-inc world-width / grid-size-x, a# N$ D/ W8 h5 M1 S- g6 w- H
set grid-y-inc world-height / grid-size-y
# c8 g+ \; ?& Q! P; ?0 R0 F) U6 l, k
% R4 }3 B* _8 ~0 k2 x ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary9 S. Y% ?3 Y3 L, w0 p1 h! |1 w
set acceleration 0.099& M3 w& }6 o6 m A! k2 }6 v- u
end
$ r# `- r: s. R
) i- C) y8 m' F& D- @+ |2 v6 D;; Make the patches have appropriate colors, set up the roads and intersections agentsets,! B' E& ]3 {# K4 X
;; and initialize the traffic lights to one setting4 Z4 m3 {3 @7 I9 [! B+ Y' ~
to setup-patches
; u8 a4 C! d& M/ H; E3 z+ [6 G3 G ;; initialize the patch-owned variables and color the patches to a base-color
) h& r" W" {0 `6 l4 e ask patches
N3 u1 _8 S3 r4 ^8 l" O: m4 T. Y [' @9 f% F# i+ `
set intersection? false2 }8 R. P6 g, f+ I
set auto? false, z T! I% q$ e4 d9 I; @$ D
set green-light-up? true
6 V r. {! q9 K7 t set my-row -1) n: j* D' B1 ~3 `, N: l
set my-column -1
/ \. d4 }, j- X$ M& r set my-phase -1
4 h$ l6 p2 |) X3 V$ \$ P1 N8 X1 |5 o set pcolor brown + 3
" }' ~/ k9 {0 I9 N$ s+ Z- T ]
4 {* u4 r; _( r0 b: K) s, a) G& I* R
;; initialize the global variables that hold patch agentsets; W1 s6 C! d+ m: I+ l* g$ `: ~
set roads patches with
( d* J+ I8 z6 J+ { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 N+ @/ I: l% w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ s2 B+ @/ v: }2 N set intersections roads with
% h+ O! [4 g% L* Q4 n6 U! t/ o [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
( p+ U; N, i3 V4 a# P5 E' j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! B) ?6 N4 D. _) u8 x0 b Q9 x& U) F! {% |, I6 J
ask roads [ set pcolor white ]2 l) l3 [; r' O
setup-intersections/ [: ?, ^+ i+ t1 c
end
8 r. D: m1 j) |其中定义道路的句子,如下所示,是什么意思啊?6 m! E, j4 v, V
set roads patches with
( {: z% s0 R/ |2 f5 C, ~" i2 p. a# T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( _ T" a; X) J+ q- F C8 S9 l# H (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
X2 c. m8 w$ @% u3 B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? |
|