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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。
1 |: p& o& g8 D R# P9 snetlogo自带的social science--traffic grid这一例子当中,
: k7 X$ T2 z, F- I5 ^5 ^1 t" O& |: Nglobals
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$ I* F) `1 ^3 l grid-x-inc ;; the amount of patches in between two roads in the x direction$ X: m. x' S$ w$ i
grid-y-inc ;; the amount of patches in between two roads in the y direction
/ [ U3 z& c, \- B acceleration ;; the constant that controls how much a car speeds up or slows down by if
9 Q/ {9 R |7 h# D% l ;; it is to accelerate or decelerate
4 a2 A) e7 B2 \/ ^ phase ;; keeps track of the phase$ t- R' d$ m) W5 s7 r
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# X+ w! e! F1 ~2 o4 O current-light ;; the currently selected light3 v" ]! s) {9 a/ ]$ K) }
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;; patch agentsets, g' f9 P0 h/ B- y* s
intersections ;; agentset containing the patches that are intersections6 c* B% F! ^2 P9 K1 g7 W
roads ;; agentset containing the patches that are roads
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, j% x/ C# d- A( q1 uturtles-own" v. {! ^: Y" l+ Q
[
( U* U& w5 C/ l( p speed ;; the speed of the turtle9 C1 }9 D+ {0 m* l
up-car? ;; true if the turtle moves downwards and false if it moves to the right
% n" D$ H# x1 d; L" Z1 @% O wait-time ;; the amount of time since the last time a turtle has moved3 l" o. s# A) G: {+ V! O+ g
]
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9 a* |# _% w2 q$ h9 r* c! ypatches-own
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9 U6 ~4 K. G9 g" c* I$ m7 I intersection? ;; true if the patch is at the intersection of two roads9 Y6 a* E' C, M* D
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
* k$ R B5 Z5 ^- F7 w. | ;; false for a non-intersection patches.# K6 o5 \) q1 b4 e
my-row ;; the row of the intersection counting from the upper left corner of the8 w! y) v) A9 t* f( w& I% ^
;; world. -1 for non-intersection patches.- L6 j" t0 O! u
my-column ;; the column of the intersection counting from the upper left corner of the7 r: H" C4 v* `8 A) J2 G
;; world. -1 for non-intersection patches.
2 T }$ p8 ~6 R: R4 _9 [ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
( I: z$ u3 @' A8 C5 `4 J8 v auto? ;; whether or not this intersection will switch automatically., J% r; }4 Y% P3 M" ^
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
4 _0 m Q, N' y! K' @0 };; Setup Procedures ;;& c$ v7 D7 p8 N
;;;;;;;;;;;;;;;;;;;;;;
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, _% s( O8 O( u3 Z# t% n' b% z;; Initialize the display by giving the global and patch variables initial values.7 a* i& {4 d; A0 G
;; Create num-cars of turtles if there are enough road patches for one turtle to
. A& a G6 T f! d6 P1 e8 J;; be created per road patch. Set up the plots.
" l* A: f- z5 c* N# H- K, d, T9 K7 u& Vto setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables; u" W3 V8 ]1 E
setup-patches) q) y2 d5 }, b. X
make-current one-of intersections
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set-default-shape turtles "car"/ B! P9 M5 K ] H" _( \# z( Z" W
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if (num-cars > count roads)' ?9 E s# `+ q7 ]7 x2 e
[
2 i; u4 h3 y* A; F8 D. r5 F) V user-message (word "There are too many cars for the amount of "
+ }8 ?- m! E0 V: P" Z "road. Either increase the amount of roads "' ]. e1 G% _. H( s0 l/ }! z9 l
"by increasing the GRID-SIZE-X or "
2 ?. T9 A' k5 W# t+ U! \ "GRID-SIZE-Y sliders, or decrease the "
. l4 j3 Q, N5 i/ z% a "number of cars by lowering the NUMBER slider.\n"7 ?: m# p; r' z* C% m \9 z5 D
"The setup has stopped.")2 c1 [ A: S0 T/ U" T
stop+ g3 y5 t& b) g5 x4 n5 S* ]7 Y
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6 L5 r5 D# x! H$ Q C( g1 c ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
! a2 |1 r7 Z5 R C: a( W! R; E; i crt num-cars
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8 E4 m. G' o+ m% U2 w setup-cars
3 v. |, |5 z7 c2 V2 V# K set-car-color0 Q3 P! v* h7 P4 K
record-data+ `: Y1 h6 I* ?+ ~1 q
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;; give the turtles an initial speed `; s3 T; n& B& K
ask turtles [ set-car-speed ] Q3 c& O, T4 k8 o6 ?
, `8 l0 [4 } ` \3 p% `) d reset-ticks
5 i2 l6 Q9 A; ^5 } d [3 s& ?end
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: Y& w( {! r1 L/ s+ Z;; Initialize the global variables to appropriate values, [6 L" N! _$ G3 A O0 [/ C
to setup-globals4 S! k6 S* _: ]; o$ J
set current-light nobody ;; just for now, since there are no lights yet
P8 {5 x, Q: `+ p3 x* w) A' G set phase 0
. v/ a& `- h( A" f& b$ J set num-cars-stopped 0$ _- e7 Z& R# L8 Z [& E
set grid-x-inc world-width / grid-size-x
) m" J p9 L8 @' b% o; } 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& |7 a5 e$ D( @) Z6 ~0 g
set acceleration 0.099
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) K4 Y7 A" W4 G/ c4 [! p6 r;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' f9 Q' ]8 g' }0 I5 I8 v% g" O: z* \;; and initialize the traffic lights to one setting
$ g. z2 H0 [8 Q0 N# z& T# t5 Mto setup-patches
6 B; ^2 Y3 }9 \, {- ^/ Q ;; initialize the patch-owned variables and color the patches to a base-color
i" n' b; C; W: O. o ask patches8 u# l6 a: Y- \* V$ e% `4 m# z
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2 W% I$ h6 d$ R! \ ^. ] set intersection? false
1 ^3 W0 [! C x' C. |8 z/ l5 p0 Y. C set auto? false
% f2 H; n9 h- f* _ set green-light-up? true
5 u1 t% q4 U' w, Y9 k' d set my-row -11 |# g) ?* E5 _9 P S& Z
set my-column -1
) E6 L( e4 j: n; g5 F/ M- i set my-phase -1$ P) t: V7 |2 S2 |0 A* }9 D
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets' t( |0 r7 b# O/ l4 t2 v
set roads patches with
" O8 x' P. h3 Y( e( d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) l5 \0 l9 F0 w7 t4 F2 u; f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" U6 a* P9 X! P0 w# ?' i- [
set intersections roads with; x0 E$ h+ [7 `% v3 Y2 b
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and0 f( w, W* h9 @1 Z9 Y* j: f
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ K; J& _3 `5 e/ G
' s. D; y% C) G4 \0 v ask roads [ set pcolor white ]
* m* Q I$ `4 T( ?, V: N setup-intersections" k) Y" T+ P( ^* L6 S9 u) @0 i: `$ m
end
# d: o, d. [+ g) Q其中定义道路的句子,如下所示,是什么意思啊?
0 f4 {1 a5 L% q* r- C& t3 g+ |* R set roads patches with
7 ]7 a! D9 F# s) N- b* l7 l [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 X; i" ~& q; V3 t7 J( ~! ~ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]: I& g" S* n$ t2 Q3 X
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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