|
|
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。
6 n* G& u9 F7 u6 anetlogo自带的social science--traffic grid这一例子当中,
) x+ c8 z% r% W4 E3 Y4 |globals" C, P$ M% d0 T" j! K7 ^2 m: H
[
" ]! M9 Y2 `" T% M4 D grid-x-inc ;; the amount of patches in between two roads in the x direction
2 O' U! x4 W2 q8 ? grid-y-inc ;; the amount of patches in between two roads in the y direction% w+ J6 j, D; E5 ?! W* s" f
acceleration ;; the constant that controls how much a car speeds up or slows down by if2 x. x% M, g& F$ B" j. n& E$ T
;; it is to accelerate or decelerate
) k$ _" c- u M phase ;; keeps track of the phase9 L+ n) Z9 |5 s5 j5 S
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure$ ]$ D* q, V# X& M, t+ {
current-light ;; the currently selected light0 [2 B' H5 X7 n* E$ E) t! u
2 Q* ]( E; Y# L' M4 ?
;; patch agentsets
+ d( ^# |* J/ V+ ` intersections ;; agentset containing the patches that are intersections& b7 J6 ]4 y# W
roads ;; agentset containing the patches that are roads
9 M9 A; a) u4 G5 j/ _; |7 A]
& L1 Q1 O( f% V9 B8 B. p# F) {
0 u9 K `" J' I0 o- t) xturtles-own
# T. d- R A$ _9 P[( ?1 k4 W' s( w
speed ;; the speed of the turtle6 C1 W8 G8 v; c0 J. T
up-car? ;; true if the turtle moves downwards and false if it moves to the right
8 U8 {" I* e9 k3 P- S% j wait-time ;; the amount of time since the last time a turtle has moved5 G4 E9 e" `9 j+ S9 R; D. G3 w6 G
]( f) K) n1 @: z# \
3 |( i* V/ X3 @: M" l A/ Y
patches-own
( I2 [% ^' j0 k9 F1 N[6 l# C( q1 m4 G* l* w
intersection? ;; true if the patch is at the intersection of two roads
7 }; X' o% ?/ h! S8 U green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 h2 X5 y$ b5 B2 F. C* f% V6 a6 N
;; false for a non-intersection patches.) u, q$ L9 ]1 N/ k7 _
my-row ;; the row of the intersection counting from the upper left corner of the
: y% o [; w" C ;; world. -1 for non-intersection patches.
" {- Y, ]7 t# C/ ^4 a; [- q/ v4 @ my-column ;; the column of the intersection counting from the upper left corner of the. }3 f6 H1 t& \2 ~
;; world. -1 for non-intersection patches.
, ]7 @( K; ?3 z0 f9 d- X: _- E8 G my-phase ;; the phase for the intersection. -1 for non-intersection patches.
8 k) e h$ e0 N q4 V$ s( T$ Y auto? ;; whether or not this intersection will switch automatically.6 z5 @! x# n1 V
;; false for non-intersection patches.: g! ]+ S: L4 K
]
8 X9 p8 A+ f0 @+ U" A
$ o) @8 _! n" d) y3 ~( H8 ?4 o: Z
;;;;;;;;;;;;;;;;;;;;;;; [' o! i3 g4 U" ^
;; Setup Procedures ;;
; }4 ` c4 G" A( k;;;;;;;;;;;;;;;;;;;;;;& h4 ?) x# S& b7 S5 L
' p1 w' U m0 h) z4 |! e$ |;; Initialize the display by giving the global and patch variables initial values.
! U+ @2 L$ S: U+ t& h0 @* p5 z;; Create num-cars of turtles if there are enough road patches for one turtle to8 e: n, l. T+ d- `. y( b
;; be created per road patch. Set up the plots.
5 s( X' v+ Q- h, k/ `& Sto setup- s6 w" q' p. e
ca
6 X2 l% S q9 |9 e, R% [ setup-globals$ b6 l& Z: U/ H9 j9 D8 w1 u
( D/ E$ }* A) y ;; First we ask the patches to draw themselves and set up a few variables' C' @- W' R' h. p6 m
setup-patches
3 q @/ C! Y7 i' C* @* |4 h4 L make-current one-of intersections
; R& ?4 T- s- b: N5 O' Q; k label-current1 @) {, z. u3 ~$ s" p$ B) F
8 z1 B7 L: v4 f3 c2 ~
set-default-shape turtles "car", t j$ v; A5 O: d. T7 Y" D
$ B9 _, \' g& ~ if (num-cars > count roads)
9 Z9 F$ o. g7 P$ S2 a [
% J+ A4 P" ?% x1 j4 t user-message (word "There are too many cars for the amount of "5 l ?) z% k' f
"road. Either increase the amount of roads "$ l6 x/ B. S y+ U5 u, d
"by increasing the GRID-SIZE-X or "
|) A6 _/ y; J+ x/ E2 v "GRID-SIZE-Y sliders, or decrease the "# y) p9 j* w" E0 i
"number of cars by lowering the NUMBER slider.\n", w) l; b# \1 ?9 ] Z4 E4 K5 i) K
"The setup has stopped.")
, m( W. s9 d5 \& | stop
9 K, v( ? o' D4 `, M+ H5 G! c ]
. t0 z# N4 a, u; u2 m; H0 T
% J/ g0 ~, p; L2 O ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
# T( I( \( P8 ^7 K- b7 U* v crt num-cars$ S/ N+ _$ v' C% g) P
[
" Q& ~1 ]& ]$ l) h; H setup-cars1 {4 m% w$ D% B9 R- p
set-car-color- m8 v$ n5 H% f* u8 d5 E
record-data
* m( D/ d: A% k% C: L* C ]* n: O$ C- n0 |2 T
8 L* |8 G0 w) Q- k, R4 S# R- J ;; give the turtles an initial speed
0 T) D0 G5 w/ ` ask turtles [ set-car-speed ]0 _" ?5 A7 m1 K' L7 }& E1 j! L; e2 m
7 `+ `5 A3 O* i% a) h1 \ reset-ticks- I$ x B9 h* _# Q# G
end1 m+ B2 g# i1 e1 ]6 a$ C0 K2 U
r$ Z4 [8 }' {0 J! r s- u% \
;; Initialize the global variables to appropriate values
, E. B3 I, z! |! A8 U: bto setup-globals1 s0 j# e- q( x
set current-light nobody ;; just for now, since there are no lights yet
" W5 d* E+ Q' q& p% C! D set phase 0
3 o0 |1 l: ^* i9 q1 x* c$ a) s8 [9 B set num-cars-stopped 0
! i; H. F; i0 ~, ~* E, Q+ ~% Y3 D set grid-x-inc world-width / grid-size-x
8 N2 Z! j$ P6 L2 {9 b set grid-y-inc world-height / grid-size-y V1 L* S* I- F$ O- s+ M
3 o+ a7 f% }* d; X
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 Q/ w8 q0 |* e2 {0 X3 B& p9 Q. E
set acceleration 0.099
7 H* y9 ^% W) s) E3 {% S6 [end
8 S. b$ N; {& }
3 x' M( V8 u7 N. |$ t/ t2 X;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
$ L5 Z7 b# o; e, w/ E$ d# D8 t;; and initialize the traffic lights to one setting
5 o; w" i% U( `* tto setup-patches
8 Q* }6 Z. Y+ F1 c& ~, Q ;; initialize the patch-owned variables and color the patches to a base-color
. H- L: X0 w+ m; y% ` ask patches
- T7 }$ S( `) O j1 D- A [
4 Z, P, x$ P. c: q; H$ i set intersection? false4 |: E4 w4 ]- @& b4 O
set auto? false
" i) M+ B0 G) Z% x set green-light-up? true
9 p% ?/ _; T, {+ {5 w set my-row -1; I8 [- d1 K! A' o8 O8 G
set my-column -1( G. g ^3 m# W% Z8 [
set my-phase -1
# ]2 U% q) v- x- S8 u5 Z set pcolor brown + 39 u/ v. g: M" L% a8 }
]5 q6 y1 |1 z) F v1 D3 B9 q$ c( U
, _8 ?4 B7 Z1 w6 O- Z; }' y" n" f7 G
;; initialize the global variables that hold patch agentsets/ \" _7 r3 {3 s' J9 N7 w
set roads patches with! J2 `) b2 A: l' _ G) q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 ~/ B1 |# J' [7 ~ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ e; X3 P2 R$ T% ?) K
set intersections roads with1 Z% I4 f( _* O4 J; ^
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
) P9 T* d- q r8 a" b% K" I (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# o! }1 y7 w, P j
( s) n- V/ B! w `" v& |# x2 V
ask roads [ set pcolor white ]' ~% }$ P' z% v7 F% ]! Q# ]2 C- y
setup-intersections2 K* p8 h, A# Z1 d& P8 I
end
. K! _4 F7 Y( w3 N$ b其中定义道路的句子,如下所示,是什么意思啊?
5 F- o o+ _# J% i; x& ~ set roads patches with
& R6 ]( r7 g" }1 J! P [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or* b' `) \) z% e! G$ W8 q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
Z# s8 q+ k) I* R( J/ z0 m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? |
|