|
|
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 a" ?' j5 m u. znetlogo自带的social science--traffic grid这一例子当中,
) l( L! E: `3 Oglobals
g, c. Q) N f/ j[
e9 b+ _) S0 w( ?! ~, M. L4 \* O grid-x-inc ;; the amount of patches in between two roads in the x direction. F- u9 U( b( y( K/ v
grid-y-inc ;; the amount of patches in between two roads in the y direction3 C: A9 t8 P6 q0 `! M
acceleration ;; the constant that controls how much a car speeds up or slows down by if" e3 _/ ^$ c! ]/ `
;; it is to accelerate or decelerate
" Z7 Q: D0 O( h7 M phase ;; keeps track of the phase& p. w' _. u7 F# T& o
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" q' g/ _' \* \4 {7 K3 ^+ E" p9 b
current-light ;; the currently selected light. y# p- N% p6 p0 s( V7 I( p
9 }+ q6 D0 l0 p( `7 a2 o5 N+ O ;; patch agentsets) u6 e8 W' V4 o* b
intersections ;; agentset containing the patches that are intersections
+ p J/ F6 b+ r4 s( t roads ;; agentset containing the patches that are roads
0 |0 k. X' A$ g+ l O], m- D# ^" X ?6 l2 L* Q7 d
, L' x6 k' S3 `% L& {( K& S9 S# d
turtles-own" l7 L/ f* m/ V! _9 K8 ^# P4 W
[* W3 s9 s, F# {% Y/ u6 x
speed ;; the speed of the turtle. t/ Z Y% g$ ~
up-car? ;; true if the turtle moves downwards and false if it moves to the right, n. O1 f8 T/ W/ s: e/ m* \6 }
wait-time ;; the amount of time since the last time a turtle has moved B" \+ W. [8 q3 \ N$ y: F
]
; Y- s& {, T9 f8 m2 }% }7 @1 ]5 u+ ^, ?- S5 ~# a
patches-own
8 _$ J/ ^* a9 y+ C. Y4 L[
: T6 I" ~) s9 q% M: A; Y+ S intersection? ;; true if the patch is at the intersection of two roads/ z0 v( Y7 u: B/ S K& m
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
: z" ^$ G6 ]* ? ;; false for a non-intersection patches." S; ^) s( G' P9 |# `
my-row ;; the row of the intersection counting from the upper left corner of the0 Q. h$ _! L" l+ T
;; world. -1 for non-intersection patches.( i: Z2 r3 p. Q0 S1 i
my-column ;; the column of the intersection counting from the upper left corner of the
1 T: P- m( s. t+ \ ;; world. -1 for non-intersection patches./ r. b$ f5 X- {* r# b% J4 m `
my-phase ;; the phase for the intersection. -1 for non-intersection patches.- |6 o* U3 e% d& S! C1 a) p$ e
auto? ;; whether or not this intersection will switch automatically.- M7 P: `# S7 r6 l0 Z8 f# g
;; false for non-intersection patches./ @6 w: g; j7 m! _; |* B0 x
]6 R( x8 {& t5 n7 I. I
; j% V; f7 }7 H( I. ^4 G. O7 c# N& w. V/ ~# F' d
;;;;;;;;;;;;;;;;;;;;;;
. a! e1 E4 a) Y3 d2 Z- \;; Setup Procedures ;;" L1 t+ f* f( R/ e
;;;;;;;;;;;;;;;;;;;;;;
: E$ S& n$ {) W' A' ]# N
- o4 ?. l; r# j# R0 _ _$ r;; Initialize the display by giving the global and patch variables initial values.) K& [* G; }: P7 D" C( _
;; Create num-cars of turtles if there are enough road patches for one turtle to }2 A2 W( J6 N7 u' N3 T
;; be created per road patch. Set up the plots.
6 m8 ]; P+ q5 F) T/ }5 Dto setup
; K6 D' u7 q/ x: ~% G ca
1 w' V' W6 f. X) p setup-globals" U2 l7 a% C; n
; {7 k9 B! J5 I
;; First we ask the patches to draw themselves and set up a few variables
3 ?- z* C" f1 G3 i setup-patches7 s8 p' g4 C7 U! m+ n/ O' K+ B/ V
make-current one-of intersections B$ T# ~7 ?+ w( W0 w" b
label-current
7 d* V! E% _8 K/ {* n0 W5 z9 C% q6 q
set-default-shape turtles "car"0 [' N! X+ Z4 ?- l1 [% }
; s$ b; F, H+ n" e
if (num-cars > count roads)
1 a- ?/ M* L; o: A$ i [! p+ t0 D4 w1 z7 x
user-message (word "There are too many cars for the amount of "7 R" i ~/ z/ { l5 M
"road. Either increase the amount of roads "/ B% l% p7 W) `, X, t
"by increasing the GRID-SIZE-X or "& _, Y& d6 ~9 a2 p1 d) X5 `9 b/ q
"GRID-SIZE-Y sliders, or decrease the "' K9 O- q% |5 ?4 O* Y
"number of cars by lowering the NUMBER slider.\n"
1 g0 U% d L; K7 g2 R% h7 Z "The setup has stopped.")
( h( [- g* n8 N# b" { stop! Y2 V# p$ n# Z
]3 }! I9 {# `- F4 M S* S: n
+ R: ~) k$ p. X- n% ~* ?, s& w z ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color# X1 t. s$ L: ] r, q, t3 M. r
crt num-cars9 P6 v$ s- `: F7 q c6 k/ M
[( i$ _" W, [3 ?2 f! ^! x( r3 L
setup-cars
& p0 \/ V0 z+ [* w/ z0 ~- D0 d set-car-color) U% v* d, x8 `+ M
record-data3 l1 d- a' Y4 U6 x& X3 J
]3 C% M3 {& i3 i T
! g0 o# ?5 J5 H0 {; R ;; give the turtles an initial speed
6 m, S$ R/ V. L: `* l# `1 J ask turtles [ set-car-speed ]3 C6 A# O; K' Z* F
5 N4 u9 y, |) C1 k8 V9 |3 B2 A reset-ticks
6 Y5 c( v) t+ T1 f0 W; W) _1 k+ ^/ Fend& Z3 T8 b& V# ?' I; ~
( W3 j/ M' k3 \. c) \: |+ };; Initialize the global variables to appropriate values
; ^9 o8 O; O0 F% Vto setup-globals
+ i. J* B- x: m: u6 K set current-light nobody ;; just for now, since there are no lights yet
6 t9 b' B5 g/ [* `% v set phase 0
: U3 R+ N- [4 n+ x @ set num-cars-stopped 0! n5 ^; I! ^8 N8 U# p5 P6 S
set grid-x-inc world-width / grid-size-x) S% y- b: B9 E7 P7 f- V9 C# I" y
set grid-y-inc world-height / grid-size-y
, m1 y8 h' Y% j8 b) N
. i/ N; K4 }# ?" {( F" T$ t ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
% `4 B4 {! T q2 n# g! N$ N" B set acceleration 0.099; Q4 L# {% {! x. R2 ~5 _
end
. `' A/ J# G5 U1 F; J' @; _2 _1 T( G& v5 g& U2 J* G$ L
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
& s* L3 E! A- R, W8 p0 l# h' G;; and initialize the traffic lights to one setting
: [ |$ D$ S( E) bto setup-patches) g0 j6 \! D, v# j7 A. q
;; initialize the patch-owned variables and color the patches to a base-color: t: s' B- x1 Y8 n- l
ask patches
# M! j+ Y j( C0 { [
3 T( \) U& @5 B% {2 m4 R4 W. Y set intersection? false
* {" Y+ y9 A; N set auto? false
0 n; Z- [8 G+ K set green-light-up? true
" }% w; |1 S% c2 c' F. A" Z' `% o set my-row -1
) c" [, A1 K% o- N1 ]; |2 m b set my-column -1
. t, C0 {( M* @5 o0 r7 Z set my-phase -15 b& t1 [" ]7 w) x
set pcolor brown + 34 j' X! x Y1 [; T$ i* z+ r* ~5 n
]
( f- h2 S# P: x
! l3 p- d' C8 M& {, v; { ;; initialize the global variables that hold patch agentsets
* B( r f, @! ~7 o" t x( r set roads patches with
, u" _1 [8 T' ? [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: v2 W F: k4 c6 v8 f3 i (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' e/ K: z+ R6 i- F. M3 R" ]9 {
set intersections roads with
- Q) [# c3 _0 ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and/ f b+ ^! v) z6 v5 H
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
d" R5 ]! \# i/ @7 F
5 s/ @4 x- O- {8 a1 h4 V9 T+ S ask roads [ set pcolor white ]
+ ~+ Z% ?: B7 t" `- p setup-intersections2 q1 o6 \" R: x5 ?; w. y( b
end: c7 \5 K! h/ c: h7 l6 Y& ?
其中定义道路的句子,如下所示,是什么意思啊?
6 }1 f6 D' ~' o; g8 Q* y set roads patches with
' v# b0 n( y5 ?& ~: f [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" Z, s( ?5 u7 N7 a( U4 m+ S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]' Y9 E; z& O: n6 Y
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? |
|