|
|
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。
/ I6 B" y E/ X! F" a0 a4 Knetlogo自带的social science--traffic grid这一例子当中,& v5 P8 r0 q9 u. E1 G
globals) _$ B2 W( d) r* X- t7 i5 X
[" e1 k8 E7 H5 ~6 N( S+ M
grid-x-inc ;; the amount of patches in between two roads in the x direction
$ E9 d4 F2 r; Z; h) H$ E grid-y-inc ;; the amount of patches in between two roads in the y direction
- O1 J& E y7 d' U acceleration ;; the constant that controls how much a car speeds up or slows down by if
9 V' j T$ s3 h1 i* d' L ;; it is to accelerate or decelerate( L4 l/ f2 @( O) f k
phase ;; keeps track of the phase
0 W$ L9 V5 C7 B7 o2 |- G% D4 ~ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
; Y0 W; F: M r V, `. w current-light ;; the currently selected light1 g8 l$ n3 u7 e
, g8 u$ k" } T$ b M3 p" N
;; patch agentsets" K2 T/ k( f6 P& f; X+ F
intersections ;; agentset containing the patches that are intersections! d2 L4 U+ j0 K2 Y
roads ;; agentset containing the patches that are roads
) H* d$ k7 t9 t @! u% R2 u$ t]
8 c3 Y2 I1 v; f) G# m2 i- e
1 F" s- ?+ z7 _" v" W+ _turtles-own8 X, j* A( |, e$ c0 m
[
' C1 V+ D; u0 @- [ speed ;; the speed of the turtle, J& G2 g; G4 d; l4 J8 o
up-car? ;; true if the turtle moves downwards and false if it moves to the right
9 x$ f' H" C& }- N2 \! ^# B7 ^7 P wait-time ;; the amount of time since the last time a turtle has moved- L" G6 o% W, S/ A, w& t# l" V# ^+ I
]/ K& ~* N2 o6 o8 z
+ n8 c9 s9 C. v0 U$ L
patches-own
# C* [& H5 n, T% R5 O- N, H[
" \& V i* U& P+ H9 U9 X( A2 c intersection? ;; true if the patch is at the intersection of two roads
; I; U8 @, U) H4 h green-light-up? ;; true if the green light is above the intersection. otherwise, false.
4 v" V' i. P/ R ^ ;; false for a non-intersection patches.
# c' I4 H6 b/ Z W3 \4 N+ c( M7 ? my-row ;; the row of the intersection counting from the upper left corner of the0 S" ?: r* F& t' s# o7 y# m
;; world. -1 for non-intersection patches.# g! k9 s( p# @1 y6 N+ _
my-column ;; the column of the intersection counting from the upper left corner of the; P' z N: M& t3 T+ {7 E0 |8 Y
;; world. -1 for non-intersection patches.
/ f0 P- _+ S* f& N: e6 M my-phase ;; the phase for the intersection. -1 for non-intersection patches.
0 E$ h7 m- t$ b$ C- X auto? ;; whether or not this intersection will switch automatically.
' J& W0 t% f+ u/ S- Q7 C ;; false for non-intersection patches.
3 m* U* ^* A9 z]* i% F/ V0 Q* W$ v4 }# L
: \1 g8 u1 i6 F# H
; `3 @, ~! `0 i% |: D! X
;;;;;;;;;;;;;;;;;;;;;;
. O; W# r j2 ?& Y5 i;; Setup Procedures ;;- v3 R4 x9 {1 _) W
;;;;;;;;;;;;;;;;;;;;;;( {! K7 D/ Q& s* F/ N
2 Q% J1 {6 j* B+ m, a1 Y
;; Initialize the display by giving the global and patch variables initial values.* p# E; Y5 Z' {
;; Create num-cars of turtles if there are enough road patches for one turtle to
: L; y) x4 g/ S) Q7 p& ^ L' o;; be created per road patch. Set up the plots.8 l& x5 V) X V( C1 k3 H
to setup
~$ j7 K+ _1 @ ca/ d8 }0 F! ^/ w" v
setup-globals
) L7 z7 Z7 h1 \/ d" ]4 m9 F8 X+ w" \$ Q Q! D. W! B
;; First we ask the patches to draw themselves and set up a few variables
( Q9 ~$ @+ P2 I2 b setup-patches
3 l- G, }! C8 ?- P6 j# l make-current one-of intersections
; s/ [, p" D% q* r, H label-current* w* G. b% u! A1 Y9 K
4 B2 F, h) f$ \2 d; R set-default-shape turtles "car"7 E' l- g6 F4 _) g7 l
- z" `8 @! Z1 g. N if (num-cars > count roads)
9 x% V8 F. C7 h, t f2 B [9 b9 l f5 b+ t+ g* y; N, x
user-message (word "There are too many cars for the amount of "8 c) _# j* y! q* x5 w
"road. Either increase the amount of roads "
! R% u/ _( M. I9 B/ ? G* [ "by increasing the GRID-SIZE-X or "
2 c9 n2 `. }+ x+ E; k1 h, L+ T; h "GRID-SIZE-Y sliders, or decrease the "
/ @( c6 d; B1 W6 u1 m; k9 ^ "number of cars by lowering the NUMBER slider.\n"
' S2 y2 G6 t- ~7 u$ t; Q/ @ "The setup has stopped.")" V5 A+ w1 `: S* B4 U' i
stop
( h" o: }/ X) t2 F9 v& ?- E! U ]: ^5 }9 x, k7 P) Z$ e
' f6 m$ Z4 M" f* y& z0 f" _8 J, R
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color6 r. n# w" G+ Q+ z1 h$ {$ Q: e& B
crt num-cars& m3 Q+ y8 ?1 ~ g* Z( m" i
[
4 d5 b1 M( @* x setup-cars
O6 V" {* y+ A set-car-color
" q0 x- j- g- n- ]9 i# w/ i record-data" z; u/ g7 d( j! n6 p
]5 V4 e6 u! E% n0 r. G6 G0 l
% V8 @. E4 K" k6 k4 g" e2 D1 [) T ;; give the turtles an initial speed
7 }! S. X3 k {" G3 ]8 ^: o1 { ask turtles [ set-car-speed ]
: A6 |- J, r4 p- H; z
0 ~( ^- @9 y4 I0 I! i reset-ticks* k; i3 b' t f
end2 A# a' Q$ R0 D Q% H1 Y8 F+ n
' \0 D9 ^, J: m7 `;; Initialize the global variables to appropriate values
) w- K) B2 e* k" p0 ^. ]: u. Uto setup-globals
3 B8 z% k8 {* ]/ Q9 P9 _ set current-light nobody ;; just for now, since there are no lights yet
" L! j% R' g" ~) @3 N9 j set phase 0; ~- R A# X/ k1 B7 t; n
set num-cars-stopped 0
3 W& O0 }: K7 W7 N. I8 l5 k set grid-x-inc world-width / grid-size-x
+ ~, T. x+ f" A$ A9 H set grid-y-inc world-height / grid-size-y
$ r- R' G8 E) R4 k( ^
( {* @) }$ A% n; S# t6 T: \! h6 r ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
3 h' x% g- z0 [) x+ a: ?0 X9 r set acceleration 0.0990 f1 m; l( ?; n0 L- d
end N# n* ?5 g) m$ ^. [, c
6 `' G# Z! { Q/ m9 m;; Make the patches have appropriate colors, set up the roads and intersections agentsets,6 s, v+ Z% P! N7 D+ W) Y. z, G* d
;; and initialize the traffic lights to one setting+ P) E& R7 D0 [+ c/ p: u" \7 {
to setup-patches/ E$ p) h* \; ~0 R, K6 I% A
;; initialize the patch-owned variables and color the patches to a base-color' F* O: ?$ j/ z" g" [/ J
ask patches
5 R- y) i& n/ f; H [
' w8 T& H7 r g5 M) Z. p3 X set intersection? false
1 t) U9 t6 F" n& Y, K set auto? false
4 T- _9 q3 O7 |" Y& Q9 ]% A set green-light-up? true
+ ?' e2 h& e) G2 Y0 N2 E set my-row -1+ A& }, c9 g9 R
set my-column -1
5 d8 c4 n8 g% j# `$ Z set my-phase -1# I( g9 p0 f7 ^$ j8 a7 ]8 m
set pcolor brown + 3
! [2 o$ ~$ \0 p- I9 Y# Y+ Q ]
) J9 j3 v* o1 Q% G
5 `5 L( W+ V4 ]* e* c% i" B/ R) r ;; initialize the global variables that hold patch agentsets1 J7 c. O2 s9 u! _5 [% U( T' ? V
set roads patches with7 B% j9 l; n( E- ^0 q: ~
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ x* ]$ K, v7 o, B: `' p9 k: J
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 {$ n/ i4 Y; ]: Z9 s2 i
set intersections roads with; y, t2 f4 |3 _/ `4 S, a3 v
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
5 o* v0 j4 d g& \8 x1 L (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# x* H* C# o0 P/ \$ B& t: E! N% t5 A* S9 w
ask roads [ set pcolor white ]- u" }0 Y% P( l4 v
setup-intersections
" ?8 F+ A4 T' M O# Z4 Xend
2 P. X* i. p3 x3 C4 C" h9 Q* c! P5 r其中定义道路的句子,如下所示,是什么意思啊?
) B4 V) m1 H6 Q. R/ L1 h r set roads patches with9 u8 t6 h/ o" \' |( p2 ]* j% x
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 p( O+ x) x; z+ \0 | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 N7 o* J3 S" Y4 M. C% ^' r3 T3 N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? |
|