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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。
. b" c3 `* S; D; {- }netlogo自带的social science--traffic grid这一例子当中,- K; K5 `: B, R, a5 E7 T
globals
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& D0 ]- z' i! v) t grid-x-inc ;; the amount of patches in between two roads in the x direction7 ]0 m/ ^! T) C4 w
grid-y-inc ;; the amount of patches in between two roads in the y direction) A, f, O. k$ G9 V+ j/ E7 \1 h" \
acceleration ;; the constant that controls how much a car speeds up or slows down by if1 N9 v R3 _4 [$ |0 x
;; it is to accelerate or decelerate
/ j7 ^& K/ p( n) }0 W phase ;; keeps track of the phase
1 q- u. O( M2 L" @3 y% F num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# N7 ]+ |# p4 q' |5 U current-light ;; the currently selected light
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2 j4 `' |% b1 x2 J8 { ;; patch agentsets
3 H9 n/ q1 u1 m" v intersections ;; agentset containing the patches that are intersections
5 } `# _; y6 g$ V, t. W3 g2 J. |' E roads ;; agentset containing the patches that are roads) e/ V& u$ y4 n: |6 }) x6 J0 V
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* r- |6 x% d2 [! b( D" u, eturtles-own3 T8 A4 N" ~! G. a" A* @
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speed ;; the speed of the turtle7 S" v+ }1 b0 M" f; c+ ~
up-car? ;; true if the turtle moves downwards and false if it moves to the right" ]- E9 v+ t( _! T
wait-time ;; the amount of time since the last time a turtle has moved# {& T$ H+ M$ T) U- e! r+ ^
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patches-own
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4 O3 O# y- p$ _' { intersection? ;; true if the patch is at the intersection of two roads2 s/ C/ G$ G6 _; \- Z
green-light-up? ;; true if the green light is above the intersection. otherwise, false.. a3 W0 \! _+ J6 H ] s( q; e4 @; P
;; false for a non-intersection patches.
2 T7 n! a8 h8 R/ u* R, T4 c my-row ;; the row of the intersection counting from the upper left corner of the
1 l" a3 B( ]5 |- i6 G5 t ;; world. -1 for non-intersection patches.! ^" \0 r, B( J. s+ `! ^
my-column ;; the column of the intersection counting from the upper left corner of the. u4 j. h& b0 h; X
;; world. -1 for non-intersection patches.
& w* `) u) S+ `% a; d, @ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
1 H" B! Y' U2 C/ ~5 ^/ |# o auto? ;; whether or not this intersection will switch automatically.
5 c1 d+ W" P/ g# H5 l) z- A- W ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;# c% g) L$ v2 M# v
;; Setup Procedures ;;
4 j1 v/ L5 n% c( k7 \5 q;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.( m# z T9 H! h. j; L9 ^! h
;; Create num-cars of turtles if there are enough road patches for one turtle to
$ j! f9 P( S8 V3 D1 R7 d;; be created per road patch. Set up the plots.
' n+ b; o7 N' x6 `' Lto setup
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& e0 k. v; v7 @7 h( |& a setup-globals- ?* ^- u- m" T7 j
9 n# H0 t S* S ;; First we ask the patches to draw themselves and set up a few variables- v" N; |9 ^- L& _# B
setup-patches* y2 N9 `7 d" B1 j( \& h' x& ^9 Z
make-current one-of intersections; w" R' @- \% U7 Q) J5 y
label-current ?" U: D8 t0 K& L5 V- Z% x: B. H
( m6 Z* R8 H. @ set-default-shape turtles "car"
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if (num-cars > count roads)
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* V5 \ G0 U' Z/ w- m user-message (word "There are too many cars for the amount of ", n) i$ E7 [/ s8 Y& i8 S8 s# U
"road. Either increase the amount of roads "9 O% W+ k1 X7 G$ X( \
"by increasing the GRID-SIZE-X or "
& D! ?6 V! Y+ u X5 v. n" a "GRID-SIZE-Y sliders, or decrease the "
* U ^; I3 f1 C( f! k3 ]8 g "number of cars by lowering the NUMBER slider.\n"
/ x$ o) k. j" F6 r$ d "The setup has stopped.")
G) J: R+ v. K& E8 [/ t+ y stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color& |- G' d% ^% K( l, q
crt num-cars
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2 W, t1 \5 B3 d9 v% F' O setup-cars
( f, J. `. E% s+ f set-car-color$ t, a K: B) d5 K1 Y, v$ a) w+ E
record-data0 D8 \( F: [% C; n4 L' n
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;; give the turtles an initial speed; G8 A1 U. z2 p
ask turtles [ set-car-speed ]
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reset-ticks( A1 B& G( w2 r* W& j) p8 E
end
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5 f* G" Y$ c. Y# {;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet6 |6 D7 X# {3 R* V7 n: Y
set phase 0
5 d: ^# N. @" e; d; H, I set num-cars-stopped 0! t5 g e) f- m2 b6 k6 m
set grid-x-inc world-width / grid-size-x
! k! L) G; X1 l6 X4 o% G: G6 b4 ` set grid-y-inc world-height / grid-size-y
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4 p5 y& t$ i! c- S! R; u% h ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
# u4 V, Z* k Q" t set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
x3 x9 [. J. J5 I7 `9 x% y% e;; and initialize the traffic lights to one setting" C! [# _/ ?6 R+ Y- o" u
to setup-patches
, _4 d7 [3 [2 B% i ;; initialize the patch-owned variables and color the patches to a base-color0 f, V# `% b3 M9 w( w9 ^, a
ask patches# k8 z* T: G6 |1 T
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set intersection? false
. I% b8 J$ F% w3 l+ C, B4 Y$ t+ m( @! W set auto? false
# O d& q$ i9 {9 \* F% C set green-light-up? true
& L* i6 M T. d6 I; K# s set my-row -1
' N K4 A- r6 D7 y- U: M set my-column -1
, M& M1 j8 z) A7 o set my-phase -1& h4 W% @- o1 ^& r9 `
set pcolor brown + 3 ~7 y2 W4 K) M/ e& C9 v4 [% c
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;; initialize the global variables that hold patch agentsets
! p- I6 X- ^/ W3 q0 m set roads patches with
# n6 ?) F1 T; l, j* u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" c0 v. J3 ^) M! W" A1 |0 y (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' p4 L6 ~ l3 ~2 r$ G% p7 C4 w
set intersections roads with
, N9 H; D" |2 X% H% h [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ m! d6 f" O4 }( s) n (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end7 C8 D( x9 s4 w6 U9 e
其中定义道路的句子,如下所示,是什么意思啊?, L: O1 \' p6 u) x0 d
set roads patches with
( W& K) {* C% h B' D, c [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( X$ S+ c6 o9 K0 N p (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ Y9 `2 [6 d+ l
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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