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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。
^4 a' i+ o9 N% pnetlogo自带的social science--traffic grid这一例子当中,
8 `' W: r1 J9 f* M; b7 ?& A3 `4 _globals* C( { I+ d1 p I8 J
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grid-x-inc ;; the amount of patches in between two roads in the x direction
: w! P: ?1 \- Z: G) `9 u grid-y-inc ;; the amount of patches in between two roads in the y direction! ~7 l1 h8 G3 P: @- I# {
acceleration ;; the constant that controls how much a car speeds up or slows down by if
7 _* _% \5 X- p8 B: N9 w' n3 X3 g ;; it is to accelerate or decelerate+ Z f: ?1 L8 ?! J, e. x6 G& w
phase ;; keeps track of the phase* {- j6 {" n- H
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ O" s. r, B" G4 K1 Q
current-light ;; the currently selected light
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;; patch agentsets; P& J& y* N. X' s# f" e4 |
intersections ;; agentset containing the patches that are intersections K! }& K$ J/ o) ]2 Z0 p O3 j1 g
roads ;; agentset containing the patches that are roads" G! z+ G, K2 G
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turtles-own
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speed ;; the speed of the turtle
$ h! o2 A" |4 N) q4 a up-car? ;; true if the turtle moves downwards and false if it moves to the right
7 C) F8 g) N5 y wait-time ;; the amount of time since the last time a turtle has moved
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patches-own+ b* i1 o/ C( [$ o6 [
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intersection? ;; true if the patch is at the intersection of two roads
. V* L' F Z. o6 c: }3 P green-light-up? ;; true if the green light is above the intersection. otherwise, false.% c/ Z4 k- _3 Y: b! I4 E% W0 T
;; false for a non-intersection patches.4 S8 A: }) [% B, J
my-row ;; the row of the intersection counting from the upper left corner of the
& f8 K7 {9 P- d$ i$ T5 ]( |. J5 i o ;; world. -1 for non-intersection patches.! z+ K8 O* w9 X. C
my-column ;; the column of the intersection counting from the upper left corner of the
3 t9 D3 y6 {4 w+ g( X8 ~) V ;; world. -1 for non-intersection patches.6 W9 w% v+ Q! i# z0 ]; ?' R
my-phase ;; the phase for the intersection. -1 for non-intersection patches.' D) U# ]4 L# i4 p+ l
auto? ;; whether or not this intersection will switch automatically.
N: ?# U9 o% P: K1 R) Y/ @ ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
! U* w0 I& i8 z) ~- g: w;; Setup Procedures ;;
7 o7 t, `% o W;;;;;;;;;;;;;;;;;;;;;;
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' }. d6 z0 p) Z;; Initialize the display by giving the global and patch variables initial values.
# j. @* ?" H: m1 Y; u;; Create num-cars of turtles if there are enough road patches for one turtle to
- i/ X0 V( J& R G, D;; be created per road patch. Set up the plots.
5 X& I l/ R. }( R8 \to setup- A" A! T' `) d) n* j) J, p
ca
0 X/ b& o0 c/ Z1 @6 o% {% L& w, Y setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
* o- r" ~! F, i1 d! ^4 d setup-patches
2 U/ N2 C7 l/ e& L3 C make-current one-of intersections
# N# m! C' a2 \+ ^4 w" s label-current
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' Y# [# _( N, T7 V set-default-shape turtles "car"
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if (num-cars > count roads)( P' z9 F8 }0 S& J1 |
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user-message (word "There are too many cars for the amount of "
0 o5 B- I- C" e# B5 K. _$ ^8 z "road. Either increase the amount of roads "4 d L/ W4 }! g, b9 h x- w
"by increasing the GRID-SIZE-X or "0 i' l5 y" u- D1 v* y3 g
"GRID-SIZE-Y sliders, or decrease the "
3 A4 [$ N! s( x/ Y& o "number of cars by lowering the NUMBER slider.\n"3 F5 v0 h# G9 W+ A! J1 e* J* @
"The setup has stopped.")
+ }0 \! f8 W3 K5 Z5 v- j* } stop
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" r% F$ |" ~6 J1 c) M ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
6 G. F: R3 N8 ^6 K$ h" l crt num-cars! `0 l+ S1 l) a
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setup-cars
c. X3 p0 q% h( m set-car-color! ?* {; H& U+ \0 P
record-data6 p# P* u8 q$ k* l; ^
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# a4 M( W& F& B0 B# Y/ ]: x ;; give the turtles an initial speed; O. a, d- R! z% o P
ask turtles [ set-car-speed ]$ f) ?7 g3 ~6 I8 h4 |' H |
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reset-ticks
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" D: w! y9 S$ j1 X4 x" \; X;; Initialize the global variables to appropriate values( b, w( z' q* B- N5 A+ G
to setup-globals* c0 C+ i6 v" g: I7 D2 k
set current-light nobody ;; just for now, since there are no lights yet% C5 r1 v& e: ]
set phase 0; C/ C+ a: I u+ ]& s
set num-cars-stopped 0
4 U# k1 t# [' r7 u2 z3 Y3 _ set grid-x-inc world-width / grid-size-x1 T. z$ ]$ d/ v- s; v' D
set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
- n2 x1 v. l/ ~ set acceleration 0.0994 s% P1 X( ^/ h, a
end" A7 X8 c- Y# p
* h F, H F% @$ S2 \0 c7 F;; Make the patches have appropriate colors, set up the roads and intersections agentsets,4 z0 w( \& w+ q- I
;; and initialize the traffic lights to one setting2 E$ j# ]# p/ _
to setup-patches; O4 j; _+ q- N
;; initialize the patch-owned variables and color the patches to a base-color
3 `, l$ V4 m# m+ F8 U2 V+ n3 {" F \ ask patches
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0 ^; [7 p4 c- L0 Z. o% P" P) [2 W set intersection? false: e7 o, J3 H3 _* b
set auto? false
' e$ S) c, e& @ set green-light-up? true4 _8 D& ^+ K& f' G9 M
set my-row -19 p( b* Y. q; X9 {$ u5 A
set my-column -1. P% p7 B% ~5 j7 r4 N
set my-phase -1
" i& D7 j+ f: {0 X2 s' z( { set pcolor brown + 3
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3 O. H( B1 q/ V1 P6 g$ e: ]7 | ;; initialize the global variables that hold patch agentsets5 ~0 X5 S- k }* D% }8 q6 ^
set roads patches with
G1 z! P# w9 h' K [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 \5 Q% P2 R& G) m/ [% _; P (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 ^" S4 h+ b; p$ q# R# x set intersections roads with
- k$ v* m) [+ u, ~6 Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
. G2 S" Z5 a& p) K$ _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]7 W% X3 K- \9 g* ~/ R8 i( X
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
: [; Q% `+ b/ X5 q set roads patches with
) R9 W5 Y) [. y7 x( X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" |8 }9 }/ d& H# }% p7 k (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 c( O0 |9 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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