|
|
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。7 R! t9 X5 i3 D
netlogo自带的social science--traffic grid这一例子当中,
3 i6 G, o; S6 _# b+ h: i6 z& k1 ]globals7 p) ~$ f5 \7 q0 ~
[
/ y" K& @3 `6 l9 t; x grid-x-inc ;; the amount of patches in between two roads in the x direction5 W4 W! P% x- t: G: O1 Y
grid-y-inc ;; the amount of patches in between two roads in the y direction
' o6 h. a/ [+ k% B4 t acceleration ;; the constant that controls how much a car speeds up or slows down by if
, F' l; Q# ]$ V+ }4 j& L ;; it is to accelerate or decelerate
& p* g1 b& p- n phase ;; keeps track of the phase/ n: \8 `+ W' r5 Q
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
$ A" q6 J7 B6 m j* A) a- A1 ^" M; x current-light ;; the currently selected light
( k! o3 E7 w2 \! z; l+ v& x5 t
/ c8 x/ I* j$ h: Q) _+ P ;; patch agentsets
6 k/ {8 ~$ G- @ intersections ;; agentset containing the patches that are intersections
/ F6 r# S, N1 [) ] roads ;; agentset containing the patches that are roads
$ }$ X6 F h0 _6 k+ ]]7 l* W! R& Z2 s: R) k9 l, M7 c
) Y' [5 r" _( L2 V4 w$ }
turtles-own
1 m. p4 [- }; W( ]' n[7 T- W' D2 P' u2 T- T
speed ;; the speed of the turtle
3 `, {" Q K6 M; W" ~ up-car? ;; true if the turtle moves downwards and false if it moves to the right- Z1 X `9 ~5 o. ?4 v
wait-time ;; the amount of time since the last time a turtle has moved- V$ M" N. H; e3 j8 P
]8 v$ i4 k l( L
! z' H* l1 S3 Gpatches-own5 u3 x/ _2 w. s$ T ^* E
[1 i- W( w. [2 e3 p+ E) X$ i* i
intersection? ;; true if the patch is at the intersection of two roads
- T% K$ ^& o8 V8 @, s4 O green-light-up? ;; true if the green light is above the intersection. otherwise, false.
. t: G) }: z3 ]$ K% ~. U ;; false for a non-intersection patches.+ t: |3 O: ~' Z' L, c
my-row ;; the row of the intersection counting from the upper left corner of the
) S4 W" f' ]; A' t, S+ Z ;; world. -1 for non-intersection patches.
8 I# ?) I4 L/ U# h5 ^( u V my-column ;; the column of the intersection counting from the upper left corner of the
% b9 ]2 {' n# S0 O) o$ ^) n+ T7 K$ h ;; world. -1 for non-intersection patches.
6 W; b U+ O; S; J5 N3 r my-phase ;; the phase for the intersection. -1 for non-intersection patches.9 c# z" Y9 y+ E0 ]% E
auto? ;; whether or not this intersection will switch automatically.# C/ I$ g! g4 Q9 T$ l: |8 b j
;; false for non-intersection patches.7 v' e; {6 V) Z
]
" m/ b E9 T7 b% I
C- v+ W5 c/ Q; Y& ~. E! j* {
: i6 g1 J2 E6 r7 z;;;;;;;;;;;;;;;;;;;;;;$ w# W( Q& Y7 R/ E' ~
;; Setup Procedures ;;* \' e- H, E: Q4 d% j
;;;;;;;;;;;;;;;;;;;;;;, R' @3 l o) H& c; }, f& G) K
3 B* S3 O. r+ V;; Initialize the display by giving the global and patch variables initial values.% y, C3 O7 n3 j1 v! ?9 I
;; Create num-cars of turtles if there are enough road patches for one turtle to
|; O2 M& C" z6 y6 N9 Y) H: n;; be created per road patch. Set up the plots.1 R4 Z, e- A2 R j
to setup9 q' w) m9 G. [8 a' t D
ca8 R9 a* _& Y) D3 c$ c3 m1 T
setup-globals
9 c; V" h" Y$ n
$ F& a q4 U9 S1 J* l( |1 b ;; First we ask the patches to draw themselves and set up a few variables s" i5 ` i+ l2 G( n$ i( y) z
setup-patches
% @& Q, h8 T& r/ ~ make-current one-of intersections
# Z% K" V5 c- F. o. A2 s4 D2 v label-current
0 [% G. }; p" L# C- O5 h$ x' L) y# z P* M }4 l- x, Y' i
set-default-shape turtles "car"
( V4 Z; A3 w& i+ R1 T3 U3 d* n: d* i* A; S9 r
if (num-cars > count roads)
0 _' u( d) C% A% R( p# z5 g [
7 e2 d' r& x6 Q; [ user-message (word "There are too many cars for the amount of "8 c' f6 ?/ [% q& \2 V
"road. Either increase the amount of roads "
9 D& ]) U& A7 j( b. R* H "by increasing the GRID-SIZE-X or "& E. r8 Q; y/ x( \
"GRID-SIZE-Y sliders, or decrease the "
7 P1 W6 s1 ^4 Y" P2 @/ ?0 \) ` "number of cars by lowering the NUMBER slider.\n"
# M- T% o. H3 W1 {! G- C4 a" |1 j "The setup has stopped.")& Z% Q* \9 z& F! ^6 r
stop1 i; c! o8 s; U% n+ c
]
" }3 u2 ^$ b7 ]( R
7 M6 n0 Y- V4 i/ k. g8 {/ i' g) A ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
1 ^- g0 L0 r3 W0 w. | crt num-cars* x' l# B0 |- S. ]$ I
[$ T7 ]5 X" |9 t% N
setup-cars
* z$ u1 u8 x( | set-car-color
3 @3 O3 C9 |9 y" O( S% Q" ^# d/ ` record-data, z4 ~/ d: {- p# o) B
]
1 r9 R' d& a: _! P8 ~/ ?
) M+ f( Q7 T: K4 u ;; give the turtles an initial speed6 Q. w' P; h" n* r) f
ask turtles [ set-car-speed ]* w2 K. v. ~5 q$ I* P
p: d2 v5 u6 l7 {: }: J" S! m
reset-ticks
% E9 j- C' I! Gend* s) z; |, K2 U9 D
0 I' k/ u, c7 U1 z) q; G; b+ \
;; Initialize the global variables to appropriate values4 |8 ?2 L1 o! M) }
to setup-globals
G2 C+ c, }( b7 Z9 I5 d set current-light nobody ;; just for now, since there are no lights yet$ D% S, V1 D, H6 b$ V+ P
set phase 0
. d% _/ k( {( ~1 p8 g, N set num-cars-stopped 0 i/ v4 i' n3 I; d& m
set grid-x-inc world-width / grid-size-x f' h3 Z! G: d: O: X, @1 {
set grid-y-inc world-height / grid-size-y! {- I5 o2 {7 D( L2 z
, [7 V" z) w' K3 S" y
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary, \# e: l# O: {# R0 ^. x2 D+ X
set acceleration 0.099
4 T5 N9 O6 |' h$ a: ~+ ?2 dend* U% _* C. t2 g- Z% Q
7 O4 [1 _ T0 E* r+ T
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
7 p! T) U: r# C0 i9 C0 l& };; and initialize the traffic lights to one setting5 Y+ o0 ]( t' j3 v. S
to setup-patches8 j* ?( z w, d1 R& W5 T
;; initialize the patch-owned variables and color the patches to a base-color8 ~- z8 _9 o2 O& B
ask patches) A4 V& i; x8 n
[5 m' M# `* ~3 x+ {. w* W% `0 ]1 ]
set intersection? false5 N0 b! \7 ^. b) n8 q+ Z s+ P% |
set auto? false
) A, S I$ W/ U( j+ ^2 i" E set green-light-up? true1 `2 `8 J. I7 G2 [8 F
set my-row -1) h4 S; Y9 ]1 m. s6 Q- |
set my-column -1) i' m+ R. \+ P4 ~# P; R
set my-phase -1
8 i. a9 f2 c, E7 ]) ?6 C set pcolor brown + 37 L8 T, M+ u' T: j2 `$ K( u
]
9 Z: X9 F, S& P2 ~7 R- X S+ ~
1 V1 g; @' l' W: Q6 x ;; initialize the global variables that hold patch agentsets
9 K E5 h+ Q& p2 U4 k# Q8 L6 J set roads patches with. i/ k7 X: C; s' f1 `. c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 c% W, h3 g/ `9 W (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ u# R7 V) @0 Z0 R( t2 z5 F
set intersections roads with
) h1 S5 s8 b* b& e. E: O [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and) p4 }! D$ M# K$ ~7 y3 _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 c9 L; a8 Y9 y4 \6 W
0 A q) G, h# o( U7 V; [
ask roads [ set pcolor white ]
) S5 F* x8 Z' n2 U2 O9 P% ]6 x' g setup-intersections
* S; }9 v! e- M: \, O3 Fend
6 R4 X5 ~- R7 {! u: E7 U) D其中定义道路的句子,如下所示,是什么意思啊?! C: p$ J1 g. v9 Z; k
set roads patches with
$ c( _ q' \4 s' r3 s3 C+ t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% \! c* b0 w$ `4 l (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 h4 ?6 }: J- _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? |
|