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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。
& m+ ^; o1 _! O( J. @% anetlogo自带的social science--traffic grid这一例子当中,
/ e* _4 e) P1 K6 v* C7 G/ E! nglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction! ^8 h4 M$ g! p
grid-y-inc ;; the amount of patches in between two roads in the y direction
: t$ ^# P6 J. ?9 m1 ~$ l/ ] acceleration ;; the constant that controls how much a car speeds up or slows down by if$ Q( S$ L8 d# o) p$ v
;; it is to accelerate or decelerate
& h" l! F: B/ ]9 d* ]/ K phase ;; keeps track of the phase
8 c# V: ^4 K4 H! |- T: h8 _ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
7 v% ]7 B+ z" R, N1 T1 s# V current-light ;; the currently selected light5 G/ @& e, F( _$ ]' M) `
) }5 j2 z- b" U7 Z! T ;; patch agentsets3 [# G& A; `( A1 _
intersections ;; agentset containing the patches that are intersections
' D9 ]. [. h+ L4 k3 @1 J! M! e9 T roads ;; agentset containing the patches that are roads
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turtles-own( h) Z [: s9 y* M" J) u+ c
[
7 K% ^( w+ d4 I) n# {1 G$ @: k0 D speed ;; the speed of the turtle# d2 u6 Z6 q1 ]' V. f* _2 _ F
up-car? ;; true if the turtle moves downwards and false if it moves to the right
2 ~- h% n( O/ ~3 |7 g, U( w% ? wait-time ;; the amount of time since the last time a turtle has moved4 O% j; V+ b- x$ b( H
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patches-own* @& x4 e. K( _: u* z& g
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) C$ z2 e/ i7 \5 m intersection? ;; true if the patch is at the intersection of two roads
4 x& Y' Y8 E# x, c! ] green-light-up? ;; true if the green light is above the intersection. otherwise, false.% J/ O# p9 I' a/ Z5 t' {
;; false for a non-intersection patches.
* p2 G3 N: _% g" ~/ q; h my-row ;; the row of the intersection counting from the upper left corner of the- j5 P+ x5 Y, W9 @: }/ q3 m8 Y' I
;; world. -1 for non-intersection patches.
; z! i+ L7 {8 g/ Y my-column ;; the column of the intersection counting from the upper left corner of the) V: ^' G5 K. {% N9 {7 P: x# W
;; world. -1 for non-intersection patches., a% T- A/ E) h9 W6 I7 @$ |' z
my-phase ;; the phase for the intersection. -1 for non-intersection patches.& L6 G( |3 i+ x% V! n7 y' Z9 i
auto? ;; whether or not this intersection will switch automatically.0 I2 L" b* v J# M
;; false for non-intersection patches.! I7 {7 q; l# x( h
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" i6 ^6 ^" A7 j, k9 O;;;;;;;;;;;;;;;;;;;;;;
9 ?9 U; p4 h G;; Setup Procedures ;;6 _1 N# a+ u9 t7 Q
;;;;;;;;;;;;;;;;;;;;;;
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$ |7 N# Y" o1 h [8 n;; Initialize the display by giving the global and patch variables initial values.
& u% C# U* ?* o: q/ u;; Create num-cars of turtles if there are enough road patches for one turtle to
+ @1 m6 U) u1 }% p( D* b- `" S;; be created per road patch. Set up the plots.
- O8 c8 H6 k5 S6 T3 U0 u2 i/ Pto setup
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0 ~+ Z! D! f% E& l+ U. {9 J9 U! I setup-globals
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;; First we ask the patches to draw themselves and set up a few variables w; ]. O# x7 P7 l/ c
setup-patches/ k, x0 ]4 u q5 [$ {* Y% Z
make-current one-of intersections7 l0 T0 O0 w. l; A
label-current
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) d+ n* e, W! q2 B- E/ ~ set-default-shape turtles "car". j# R& Y" R* g' X+ d
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if (num-cars > count roads)
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( a6 Q+ d- C/ ^& a2 S user-message (word "There are too many cars for the amount of "
# k+ W4 K& W- R. M: l "road. Either increase the amount of roads "
5 @; T2 ]) Q9 y, b "by increasing the GRID-SIZE-X or "
" E2 [8 ~4 B2 ], G7 s "GRID-SIZE-Y sliders, or decrease the "
6 |5 Y% l. x1 M g4 C "number of cars by lowering the NUMBER slider.\n"
$ S3 o& V/ I8 @5 V( |4 S/ t: e "The setup has stopped.")
/ W, ?9 l' s7 d* V stop, `% S L! u! v2 `" {$ O4 H6 k3 S
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color- l* w3 h- T$ O/ \2 {& D- C
crt num-cars* q$ [% d t4 l5 T; p( e3 F
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setup-cars9 F( W/ `0 [- d5 a
set-car-color4 L) H/ Y0 F0 c- `2 c
record-data' K- W8 W- z5 v7 Z* Z
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;; give the turtles an initial speed1 J4 [. D$ T8 o4 }9 G6 a- F0 q: s4 K
ask turtles [ set-car-speed ]
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% u# b: l, A& V* F5 n# [ reset-ticks" h( r6 x' v$ p2 V k" t' F
end; u0 V0 _- `( o- k- {. }+ ~
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;; Initialize the global variables to appropriate values# c2 Z7 D4 }/ A- i$ g- A" C
to setup-globals
, ?) k6 \2 q8 \0 u# }1 E set current-light nobody ;; just for now, since there are no lights yet
3 k/ [( M' r3 W set phase 08 y( h$ h& u% b7 e: h2 g9 ]7 ?% S
set num-cars-stopped 0& O$ F) F" } i; t8 o; w8 K, C
set grid-x-inc world-width / grid-size-x" U! v7 @; Y9 H; i: f5 b n
set grid-y-inc world-height / grid-size-y2 a/ A: b' B" p$ S) D
7 Q5 c: d+ {+ L# n6 f! }& A ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary7 d+ @: B) H4 m( Q2 v/ q
set acceleration 0.0999 ^* k m# D% O7 R& V" ^
end
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?( S+ k* J8 K( D8 e. X;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
. R4 T7 n: d$ i! l;; and initialize the traffic lights to one setting
% ~ J3 ]& ^" L# t+ oto setup-patches+ I K, ?8 Q. q
;; initialize the patch-owned variables and color the patches to a base-color
9 ]" i* p# A+ `6 a( s5 l8 _6 } ask patches6 q' L/ N- [% i. w! P
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% @+ l2 Q( `; a set intersection? false
5 t9 W$ {7 | \8 z set auto? false, x9 o& o# {5 P! Y Z( O: K1 p$ ~
set green-light-up? true
/ G0 U7 g6 v$ |! Q2 M4 K! K" M set my-row -1, a4 Y9 ?# W( O0 |( v/ o
set my-column -16 R: N0 J1 i; p, J9 }
set my-phase -11 c) o; X) `2 y2 Q
set pcolor brown + 3
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" P0 b% N8 k1 G& n. H6 ?8 v ;; initialize the global variables that hold patch agentsets8 t$ c5 W! {9 K a4 q, L7 ^; `& s) E" A
set roads patches with
5 `& n$ _1 L* I! X1 q( k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
5 K7 s: I" m; S" @' U* x (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 J; o7 H% l& U/ Q& R0 M# x' a, Y% s set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ E+ t- b# f1 B% s8 R
4 i4 b, z( [7 y9 |; p3 J( I ask roads [ set pcolor white ]: e$ u; X( w8 u9 ]& p- S/ |
setup-intersections9 B% ~9 c/ U& a5 n: f: u9 E3 j G
end
/ `! m6 [# a7 Z. \4 |8 [7 _, k其中定义道路的句子,如下所示,是什么意思啊?# e* U) j# @7 D! k, q7 P
set roads patches with4 m, L- C% S. c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) u; R0 c- U# h' A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, Y( r, f# ^9 Q9 t3 }/ x0 u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? |
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