|
|
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。
, S/ Q5 ]/ g4 L) r" P2 |netlogo自带的social science--traffic grid这一例子当中,
/ e1 ^) ^1 D8 c6 B1 bglobals
, o/ ], l' {1 E: Y7 L; t[' n# ] T! B- m4 I$ J: }. G
grid-x-inc ;; the amount of patches in between two roads in the x direction& l! k- r& k5 `. x7 y# ^6 C
grid-y-inc ;; the amount of patches in between two roads in the y direction
6 r6 _$ t. ~% t+ y5 l8 W acceleration ;; the constant that controls how much a car speeds up or slows down by if
4 [3 K O; o- A: i, d5 [: j9 ~ ;; it is to accelerate or decelerate' x1 F# V; \3 _/ O- `( c0 ]
phase ;; keeps track of the phase+ d5 s/ y+ m! m2 ?3 z
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
1 P! Y l4 m& {# C current-light ;; the currently selected light7 r6 ~: l9 m# z2 {& D
0 y1 J! g2 Y' ?$ s! D# R" h& P' G ;; patch agentsets
3 b! |2 x0 B2 g2 S intersections ;; agentset containing the patches that are intersections. W% P: X" \& f8 t, v
roads ;; agentset containing the patches that are roads
2 ~% N) N4 s! v. x) P- @+ a]
O& {' E+ N9 Y+ W( d7 i8 z
{3 H% G3 m$ B$ Y2 \: |. aturtles-own
' X7 ]2 t8 X7 Y! c- `, y1 V$ c# I[' {9 B# J4 \5 V4 E6 Z% P8 f
speed ;; the speed of the turtle
% B/ a7 U/ j h7 r; A3 c up-car? ;; true if the turtle moves downwards and false if it moves to the right$ `' e: g% M/ F4 V
wait-time ;; the amount of time since the last time a turtle has moved- P8 G6 S9 a( v3 v! e$ a
]9 B) y0 r" r$ }8 V7 y
! [4 S2 _6 Z% }6 L2 Y
patches-own
0 \/ ^7 O! K' a% c: y. l+ U7 y[
, v* |& K8 ^* j0 r8 p4 F% ?4 U intersection? ;; true if the patch is at the intersection of two roads
) U* W5 t6 Y, d' @% P- ]1 d green-light-up? ;; true if the green light is above the intersection. otherwise, false.6 P$ j5 q1 }1 H
;; false for a non-intersection patches.
4 d$ M8 `: b; B# m my-row ;; the row of the intersection counting from the upper left corner of the) {' W) [* a& i) |7 D9 I- b
;; world. -1 for non-intersection patches.' ]7 l! A5 l1 c4 {4 B
my-column ;; the column of the intersection counting from the upper left corner of the
2 ~" H$ F! @9 a: Z ;; world. -1 for non-intersection patches.: ]3 q. {2 u1 C: L1 I1 J
my-phase ;; the phase for the intersection. -1 for non-intersection patches.1 R8 N3 r5 I" `
auto? ;; whether or not this intersection will switch automatically.1 ]" i* ]* T' t
;; false for non-intersection patches.7 V# S3 M9 w7 k# V
]1 Z5 v8 i$ a9 T% i4 _ K+ D
# G6 x. ]7 H3 v
7 S* @& V) g% j1 Z;;;;;;;;;;;;;;;;;;;;;;: n* I/ v% h) t
;; Setup Procedures ;;2 F0 G3 s6 }2 Y
;;;;;;;;;;;;;;;;;;;;;;
- G2 D9 T9 m8 M+ h6 A
0 R. \; A+ z4 s;; Initialize the display by giving the global and patch variables initial values.
; I/ C- v( u1 q2 S;; Create num-cars of turtles if there are enough road patches for one turtle to
) x" `9 I0 k' h7 [;; be created per road patch. Set up the plots.7 P! `0 M( t" S% z# `, E
to setup
2 ]1 Q" r! x2 V- a _ ca
% C3 l& g# V& A- C5 U( S setup-globals
; o+ x E6 w( g0 R0 \
: Y3 g+ }+ Y3 R, x; Q" m2 x$ J ;; First we ask the patches to draw themselves and set up a few variables
, U/ w) o7 b, d$ ?* {0 ^ setup-patches& j) {5 T3 O7 I; S- v+ F
make-current one-of intersections
8 z& ]- S9 Q4 o label-current. Z1 W1 j3 T- t
# s) Q" F6 n9 {4 T
set-default-shape turtles "car"
! B. \6 y7 W' L1 o% X, J/ m
, t/ o+ T* ^) ^3 O. ] if (num-cars > count roads)# A: d7 S0 i6 k+ j8 @
[' ^9 g( {8 `! G' o4 v; p7 S3 j
user-message (word "There are too many cars for the amount of "
- |# ?2 i& d, @. k "road. Either increase the amount of roads "
9 w5 d" n% X$ s& t( U "by increasing the GRID-SIZE-X or "
2 q7 c0 C- @ J3 j "GRID-SIZE-Y sliders, or decrease the "
: v+ W$ r7 m- W1 Y$ ^ "number of cars by lowering the NUMBER slider.\n"
, ?. ~% }/ s4 [0 L/ t% m5 v "The setup has stopped.")
, z8 X d# S1 ]5 M: H stop8 J9 v6 m' Z7 Q
]
/ k( w7 y; O, V, g9 p% X" S& H
' O' g$ E& t8 m3 i7 p# K ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
x/ E% T# o+ [3 A( T: c+ R7 v crt num-cars, v9 h6 q) a! u+ A' i# j1 Z
[
# N- Z" B$ P9 U1 b setup-cars+ F) q1 A7 f; L" |% i( c$ b. |, ?
set-car-color
& z& e q4 z- V+ n5 @' L" Y, _ record-data/ l3 C* A% l4 |
]: t+ N! n" z" _: _3 I! }" W
# }4 @1 a& }; i% U
;; give the turtles an initial speed8 E4 ?* \+ L9 W: ?
ask turtles [ set-car-speed ]
6 V1 J( ^) t; b8 j1 _) t# F6 U' _$ ?3 h' P2 _
reset-ticks8 D [& l6 g- N- V& a1 g
end+ N7 ~) L0 f- {3 v$ |/ }- c, \
- y3 D8 ~; x6 c% f6 i, }$ {;; Initialize the global variables to appropriate values
- g4 W4 h% e X/ q. A. mto setup-globals$ T, P1 ?* v& F7 k9 G. f' n
set current-light nobody ;; just for now, since there are no lights yet/ g1 u9 r* O+ a. J7 {. o
set phase 0/ q5 `& ?0 E6 n2 [9 G& {
set num-cars-stopped 0
z( d+ E$ e0 p+ n* v% ~( ]" _ set grid-x-inc world-width / grid-size-x- L& }7 W4 y1 J2 U! f% ~9 H4 h% C7 P/ y
set grid-y-inc world-height / grid-size-y
7 [$ L& g" V9 V. _! G3 L
4 t' _3 ]: X) ?: ~/ r ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# _# F; G( ]: e J set acceleration 0.099
; {- N$ v1 \- j9 k1 aend
3 }& H# P% p" v/ c, W) K- \& B/ E) s3 P% T
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
, k7 e- w7 d6 X; u: t0 ]8 N8 {- f;; and initialize the traffic lights to one setting
% ]/ o" B* W% @8 bto setup-patches5 c& r/ u9 M9 C; U+ d7 r$ `/ Z
;; initialize the patch-owned variables and color the patches to a base-color
/ i C R: I/ v( J: o) W ask patches% i! @$ s- u; t
[8 T' F9 O% e" g: J* l
set intersection? false- t' [, L2 K, }: j
set auto? false8 f. }8 P, P$ A* |, {, m4 p! \
set green-light-up? true, k. S, J7 c, `1 _' i9 X! n
set my-row -1
3 {9 N% l& ^4 {2 y- W1 z- \! ` set my-column -1
& T5 n9 S9 @# _% K6 \4 O8 }8 H5 |4 L set my-phase -1
& f( y4 E% L2 {) f set pcolor brown + 3
9 h) D" s, u3 f; k4 n ^. E c' A ]" @1 ]: q4 R- m+ B0 O- ?
d9 p. U7 e' x, K) v" V8 b B) u
;; initialize the global variables that hold patch agentsets/ G/ u9 ], U/ T- ?6 ~' ?5 P$ L
set roads patches with
% W S1 S; M# X! e0 W+ l4 ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% ?7 _0 x, g( Z3 f" l3 E: s; D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 Y0 i- M3 ]3 W# T* u
set intersections roads with# q& s$ j" s: r% m
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and- s; I' j7 N0 n: T/ O% ^
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) F2 G6 u8 Q* F3 |2 b- X" i2 K8 d0 J9 `+ ]( p$ i, b
ask roads [ set pcolor white ]
; O3 z( Z2 M2 v8 V setup-intersections9 Z" [0 R. x; @% T
end
" M3 u. P" P# ~$ I, _$ b其中定义道路的句子,如下所示,是什么意思啊?- U: s5 o7 v4 e2 `; ?
set roads patches with
$ I1 e+ s7 r0 f# v' ^) X; \. K0 } [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% f5 _% q( r7 v/ V) ~" S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% o- X' B/ }$ d, W% S
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? |
|