|
|
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 z8 ~9 d" p- c6 ^- p5 cnetlogo自带的social science--traffic grid这一例子当中,4 A- @% h+ A* B* ]- I
globals
" }& G+ A8 A2 g1 B2 p3 Q[/ d% G! t6 C- [& R. K) U, [
grid-x-inc ;; the amount of patches in between two roads in the x direction4 O# }# o2 G; U) ]0 z
grid-y-inc ;; the amount of patches in between two roads in the y direction! ^2 r4 B9 p2 a# ?; _
acceleration ;; the constant that controls how much a car speeds up or slows down by if; x7 o8 }7 `2 D; u, k+ [ l) ?
;; it is to accelerate or decelerate6 M" |* C; d9 z$ b+ j! ]& O4 h
phase ;; keeps track of the phase
- W! D& v! _) G$ I2 A) K s num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure0 R$ ], E0 n* Q2 b/ i# p0 }/ d
current-light ;; the currently selected light
' B/ ^/ F" }! ~, Q" g3 X$ ]6 d
;; patch agentsets% ?$ C1 s6 d( g- ^$ p6 F
intersections ;; agentset containing the patches that are intersections
# a2 Q$ e5 k/ W, a" E$ r roads ;; agentset containing the patches that are roads
! k9 ~0 ~6 Q! x* l3 Y) p+ c]) |4 X' I3 a7 Y8 }! ]
, s( ~) H0 O% _; q* ]
turtles-own
9 o; D% m: }5 X5 V; L; k) p[: L1 ~: a* z7 l/ o6 w+ t, U% R
speed ;; the speed of the turtle* c4 v* L0 R7 x, l
up-car? ;; true if the turtle moves downwards and false if it moves to the right3 Q2 Q4 h; p2 @/ A9 Z0 K
wait-time ;; the amount of time since the last time a turtle has moved" f$ C: j9 g& ?& D0 n/ @; q8 g& L
]/ C# d# r6 a& Y5 g1 m% e2 _9 V3 C
9 B, |: ]( P/ [/ b! qpatches-own
* j) e1 O7 z# y, j/ K[
& ], c7 P- ]# R; \; K( X intersection? ;; true if the patch is at the intersection of two roads
( V2 G# B% M3 u, R% t( } green-light-up? ;; true if the green light is above the intersection. otherwise, false.
3 m, I6 s0 Y+ L' o2 H) \ q( t ;; false for a non-intersection patches.
0 ~; e" p( q6 N0 k. B r my-row ;; the row of the intersection counting from the upper left corner of the
4 C: r! Q2 B" U) u% q9 G9 l5 J+ v ;; world. -1 for non-intersection patches.
/ N4 B% F- B$ P: x# Z. U my-column ;; the column of the intersection counting from the upper left corner of the
' q: C: {# i7 |# r# v! y ;; world. -1 for non-intersection patches.
2 Y4 R' `' u; Q my-phase ;; the phase for the intersection. -1 for non-intersection patches.
( ], j: w2 i% E: @7 c2 O; w' m auto? ;; whether or not this intersection will switch automatically.
7 `) k1 q8 _& ` h) h1 S& E4 b ;; false for non-intersection patches.: y# g' x7 h; Q
]
8 L- s4 y8 B+ m' |
. R% ^0 z; S/ u ?$ l6 J4 x2 _
;;;;;;;;;;;;;;;;;;;;;;" |* g$ z( ^$ C0 X7 J
;; Setup Procedures ;;; |8 g& ~! j% |+ I% E' x
;;;;;;;;;;;;;;;;;;;;;;
3 y+ e8 p! o* F. }
2 k, X2 ]9 H2 ^;; Initialize the display by giving the global and patch variables initial values.
/ w! ^( M- l1 @+ U& X |;; Create num-cars of turtles if there are enough road patches for one turtle to$ b# r* v, g/ K1 Q2 D* M- f
;; be created per road patch. Set up the plots.# N J1 r3 M% I6 U$ t8 N! g& Q
to setup W5 C# g! x4 F) ? o# j" o0 j
ca' c7 ^- Y! r& D% t+ l
setup-globals& p1 l8 Q! X6 E
4 i% N3 M3 {! y5 G
;; First we ask the patches to draw themselves and set up a few variables% I# Z: f7 \; }: d' y; M+ l- _* ?
setup-patches
# Y l) A( K7 }* U! C, X2 W make-current one-of intersections( s5 ]8 @0 C$ g4 G0 L5 _+ F# i
label-current
+ q5 d! ? O* e, k V+ `7 X: h4 ]$ V* {( z' Z0 R! u
set-default-shape turtles "car"2 s- J0 |1 l; n! X0 E, w
* ]- O) X( F& d7 J- N
if (num-cars > count roads)
: a! j: s* j. `* a) z, z' D [! H# V; ]# E$ R- t. u8 |
user-message (word "There are too many cars for the amount of "0 ^6 W/ N/ e9 i* ~! H' ?3 E
"road. Either increase the amount of roads "2 j0 w; ^2 B4 p3 z# z# K5 g
"by increasing the GRID-SIZE-X or "
3 N% I; A7 j! k( y, H, ^# \, R$ T "GRID-SIZE-Y sliders, or decrease the "5 W) q% b: f' F# u9 I
"number of cars by lowering the NUMBER slider.\n"
( n& }) H8 b$ |- O "The setup has stopped.")5 f! s( ^' f3 _# p$ Z
stop
. s6 W0 U9 X* J1 T+ } ]) Q n) O' Z% h6 m
' s, W6 ~7 R7 A# o
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
2 o$ x) x* _4 H$ v crt num-cars
8 Y) l# d" G N [9 \1 o, }$ W3 ~
setup-cars
. Y: T. {4 c( B0 O8 V# a set-car-color
. M3 S' _7 F! k record-data+ ^' S0 Z2 ]4 q6 V! I6 i
]6 s5 ^% w# N3 [: A- l6 k
0 w. n8 [# J( k F' G ;; give the turtles an initial speed
) L; l9 f1 F1 h ask turtles [ set-car-speed ]
3 U' n5 P, Y3 ^8 |) |1 \1 V: E
# K$ j8 ~" `6 J! H7 o- T reset-ticks* J1 r0 A1 J) t3 f
end
1 {# {! b$ N P/ M. J# a# Y& R, }; x# |+ o1 ? d; x
;; Initialize the global variables to appropriate values/ y& j/ W& _! j
to setup-globals8 {9 W1 l- ?( z0 z0 D; B
set current-light nobody ;; just for now, since there are no lights yet
' W! l+ T8 p9 c5 H: u: A, B- O- A8 \ set phase 0
7 {# ^- U5 P4 K3 w8 S0 q6 D- `. { set num-cars-stopped 0
$ T( l# ]$ G. q+ F2 Z" D* @ set grid-x-inc world-width / grid-size-x f# U( L: g J$ `6 ^
set grid-y-inc world-height / grid-size-y I% _/ S8 Q' P" a: c
( W( c7 t* n" Y' _5 s( f ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary8 ^+ s3 }' W- O0 _# G5 a4 P
set acceleration 0.0997 R, @( I( X$ U4 j, y' D% P
end
% S8 V% V/ _7 G: j l. ~. o' ?( v% z# b
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,# ]3 C! @& e" c v
;; and initialize the traffic lights to one setting
3 l9 N. `- ^, qto setup-patches
9 ?0 l; H9 n2 T# o2 e7 T ;; initialize the patch-owned variables and color the patches to a base-color
/ i* n2 G8 U/ G: ?8 j1 b ask patches6 m5 z0 v8 g! C5 t! J1 H
[
+ f, x' \+ \- H% M7 s set intersection? false9 `. ]% T l# A. Z* e* @% x
set auto? false$ B; `, L4 J! e8 a
set green-light-up? true
$ u' }) R. J1 S- w& f# W. l set my-row -1
* [4 @& L# Z, m% w2 Z8 Z' a set my-column -1
1 s R! g; \& k6 E+ p6 b* ?1 C, M6 Y set my-phase -1$ P- o) k; C, }3 \% P' p
set pcolor brown + 3) U1 H' |1 e4 r& s% B' Q
]! W# h* \0 m& B; R( _# h* ^
9 I. E, n& [' C$ p5 ~3 h
;; initialize the global variables that hold patch agentsets0 b2 L$ U+ y! c8 j6 Y& |
set roads patches with
3 u5 J/ }7 T5 u6 _( i" t: _ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* T7 d/ n) U. c' j: N5 M7 d* w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' z3 b! ~4 z5 X9 N5 o% t( w set intersections roads with
# r5 j0 E! s# S; ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
/ G& p+ E0 j- O: e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# n3 R( l# E' B
, K- U% A \4 ~- }- x8 L& V; w ask roads [ set pcolor white ]
. _, R3 |4 h3 b. s& m, E! T' | setup-intersections
6 e0 z: L1 ^0 I8 {# @end; y- I) }4 u/ `
其中定义道路的句子,如下所示,是什么意思啊?
, [6 h! ^, S% ]* U# H set roads patches with
[6 k& s) Z2 g, O } [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
5 R2 c" k9 t+ `/ P# O3 D- G5 | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 B" `+ y/ r0 [, T' d( T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? |
|