|
|
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 ], z& S% F- S! w- @* F2 Q
netlogo自带的social science--traffic grid这一例子当中," Q/ U* v3 I0 ?' ]+ X
globals
' x4 R+ i' \' K8 a! e/ W9 J* a6 D[
; N {6 M6 T9 {/ w# v: p L) W grid-x-inc ;; the amount of patches in between two roads in the x direction
# \1 h! ]! b+ C$ |& j0 X2 m# [ grid-y-inc ;; the amount of patches in between two roads in the y direction
& ]7 y+ q) D0 \, k4 R) Z t acceleration ;; the constant that controls how much a car speeds up or slows down by if' z+ c/ e4 y2 T7 C1 h5 {
;; it is to accelerate or decelerate
' q7 z$ ~" [: l! Z; F: d* a phase ;; keeps track of the phase) Z4 ~. a3 r$ Z: p: j
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
+ ?+ ]4 J X7 n$ g8 ^ current-light ;; the currently selected light3 R3 H3 h+ ~9 @$ e5 v
@/ X: P: i% u+ q1 B3 K/ t+ c4 Q ;; patch agentsets
* ]) z1 U# |- g( |9 r/ e intersections ;; agentset containing the patches that are intersections
& [& v8 I% g) S roads ;; agentset containing the patches that are roads8 W- n# W& a; L6 a
]
2 t9 Y+ k- q9 j) H7 L3 V$ X' r7 y( C z
turtles-own
) c; C6 M6 o( @2 _+ Z1 R. j[
! N- N, w9 } Y0 u6 W& N7 G speed ;; the speed of the turtle0 m s, [9 o7 J4 `
up-car? ;; true if the turtle moves downwards and false if it moves to the right
' ~( Z" `' h9 T* j wait-time ;; the amount of time since the last time a turtle has moved, ^9 U5 F# y7 N1 q0 g% l
]3 p3 F! ?; f$ \" _+ F, w: \4 h
, J* m2 X5 @7 f- u2 U/ R
patches-own* c+ `; H& K4 Z7 e% I0 \" u6 ~+ d7 V% C
[
: d% [4 U7 I2 H3 ]1 h" Q2 Q0 w intersection? ;; true if the patch is at the intersection of two roads
8 q1 K. ]7 Q* y( }( v$ O6 F green-light-up? ;; true if the green light is above the intersection. otherwise, false.
, h/ n4 d* Y" Y6 a ;; false for a non-intersection patches.
2 F1 t0 m0 d7 O0 D% W" ] my-row ;; the row of the intersection counting from the upper left corner of the( P- T# y; H# ^% {- c
;; world. -1 for non-intersection patches.
5 N* s& t+ l+ z0 j my-column ;; the column of the intersection counting from the upper left corner of the
6 t, r4 Y; [, J1 k, J ;; world. -1 for non-intersection patches.
6 C$ \3 H+ X9 v, w9 ~6 r my-phase ;; the phase for the intersection. -1 for non-intersection patches.; N/ d5 ?' k9 ^) p, c2 y9 q
auto? ;; whether or not this intersection will switch automatically. f1 C9 M$ {& ^! l. Y. ^: K
;; false for non-intersection patches.
% {. P, p$ y" T6 W5 `+ N# F; l9 y: i: g]
# L0 E1 G2 a- G% {! {% V
W( W' f! w8 o; K) P/ ~$ i0 j4 J3 U$ c$ ~+ o' X
;;;;;;;;;;;;;;;;;;;;;;2 B; L: s3 u; P, j: }8 L$ t
;; Setup Procedures ;;# f) J' p `2 Z c# F) c
;;;;;;;;;;;;;;;;;;;;;;5 ~( _: j+ x5 u8 P3 X( ^
! O; w1 u. _, {
;; Initialize the display by giving the global and patch variables initial values.
5 t& `/ l! \" ] v;; Create num-cars of turtles if there are enough road patches for one turtle to$ \1 O# D+ m4 V3 a1 i+ N
;; be created per road patch. Set up the plots.! Z6 ?3 N7 ]! T0 z
to setup
8 x8 [3 |, h, r* x2 p ca" J% S! g7 O" z' |; K' I5 l/ F
setup-globals
- u# p# r- v5 _% }" d, n) S# z
9 t$ v8 w4 U# B/ ?; S" j ;; First we ask the patches to draw themselves and set up a few variables
) h' A/ O" w" F* ]6 \2 [; e setup-patches, Q% @8 @6 q6 P# R+ ?
make-current one-of intersections
# x% H9 ]) G! J+ E% O: @ \ label-current
4 V$ c- P' {1 V: x
2 o7 w$ B' V2 Z+ i9 L! _ set-default-shape turtles "car"
' s' w7 P. I! d) x0 _- w* w
3 ^4 g g2 [! R8 p2 Q if (num-cars > count roads)
. h- U; b8 [" Q4 L# }: e+ p [
( d* L$ ?' A+ v; O+ a user-message (word "There are too many cars for the amount of "
# ^: {& y( M) I6 v "road. Either increase the amount of roads "
" ~) r) U- ?! A "by increasing the GRID-SIZE-X or "2 S$ U- f1 b/ x+ T2 Y. B
"GRID-SIZE-Y sliders, or decrease the ") \, M& O+ z- q N, T2 l1 A
"number of cars by lowering the NUMBER slider.\n": f4 r# o! k! a' R, s- b5 l
"The setup has stopped.")
: Y* W" | _, d) K stop
8 K2 X& ^ y1 |, R/ a. H ]! m" h+ @& } B$ [* S0 ~
5 s. @; L T$ j0 f5 _ T; u
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
. t3 p) a) G! u crt num-cars8 D; L4 R5 N6 e
[5 G" [. Z8 ?# f, `9 g+ P
setup-cars% A/ g% v4 B) v* h7 }- X' _7 k
set-car-color9 S% M& N, ~1 Q
record-data
. R* \+ {# R* z' o9 H K+ P4 _; ? ]+ j$ g g" j. F- m2 X' H, p9 i
$ q! ]" w) O* `+ w# s ;; give the turtles an initial speed
+ A Q* W' D( y) _) A. ^ ask turtles [ set-car-speed ]# [' A" L/ n+ T7 t! Y7 I/ j
4 X7 E9 k' C: [7 {# }0 y3 s, N/ {1 t reset-ticks
" \* E, r) C t9 {* g wend/ g4 d, d( I9 R" H5 L/ Y0 n2 s
9 Y; i7 H$ b' D" l;; Initialize the global variables to appropriate values0 G. g. r) Z* F/ Y) n+ F
to setup-globals
- ~; q/ Q: F! }" u0 ^7 P$ a set current-light nobody ;; just for now, since there are no lights yet* ?4 J& _4 d* l- B8 \8 x
set phase 0! B% G, ~3 [, T$ U
set num-cars-stopped 0- D w2 ?( s! _/ w# D; Z4 T
set grid-x-inc world-width / grid-size-x$ j& ?4 G! Z7 A3 y4 q' X3 W8 @
set grid-y-inc world-height / grid-size-y
# ]; s% `: e4 |4 }8 z- J# P" |: p* H; y- m% m$ Y% F1 A& {
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
/ [0 L9 \7 @ c& M. G' r set acceleration 0.099
5 J, I8 y- m0 k# A5 ]end
+ x/ \" S/ D" }# ]! }7 n+ Z
- N5 ?, T7 f0 X" M! ^;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
: w n! [. l( N% @3 A, L) M/ B$ Z;; and initialize the traffic lights to one setting
$ H2 X j/ P( O; @1 l: M% C7 Nto setup-patches
3 Y5 c6 w, h& t! _! g ;; initialize the patch-owned variables and color the patches to a base-color
d6 f/ s$ a/ [+ N: v1 ~% s ask patches4 K |# X( L1 d5 O3 ?
[& f# X/ F& D% b2 W5 x0 w
set intersection? false4 a* o. n( T6 L$ ^
set auto? false
% w4 i# r& w: L& K n; q set green-light-up? true% ?. T. S4 U8 q# }7 v/ v
set my-row -19 A- r5 v0 c* Z) T+ T
set my-column -1' N! v& {8 Q& |4 ^. S( A8 W% f$ F
set my-phase -1
8 Q* I( t, b, q5 ^ R; G set pcolor brown + 3
' [. d7 w2 S7 J9 s- w0 _! `' I ]" G6 S! O9 n. H8 X
" f0 M8 r2 y0 k0 S# \( I ;; initialize the global variables that hold patch agentsets( w5 F( g: p6 r
set roads patches with
8 n0 P' Q0 h& N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: M6 N- s3 f9 _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 \( h: S% v7 F1 [, Z2 b( Y V3 _( m p: E set intersections roads with5 Q$ k& x S) ^5 L& d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
3 J& m% A0 o2 `0 q Q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% T3 v: _1 M( c) U" ?! U( @0 n$ e8 l) Z4 k" B1 ]; g
ask roads [ set pcolor white ]
& `! o" O/ b0 P0 n) h setup-intersections8 G0 y- L7 k( u8 T
end! F/ o" c! E0 ]* u
其中定义道路的句子,如下所示,是什么意思啊?
" v0 [5 c: Q3 |- N( M$ S3 F- S) E; \( A# I set roads patches with# m( s: J. L4 g9 B( E3 \
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 M b! m/ d+ n4 n (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* u. C7 H& \2 e9 F
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? |
|