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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。( [8 \: E% P# [6 P; V
netlogo自带的social science--traffic grid这一例子当中,) b, h" X' \ N' T- Q' `0 h) D7 O+ \
globals
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- [: U1 d+ G/ S$ X% N+ |/ E0 ? grid-x-inc ;; the amount of patches in between two roads in the x direction
# \, j2 B# r' c9 q+ R! F grid-y-inc ;; the amount of patches in between two roads in the y direction
; k5 X4 }, F ^% X acceleration ;; the constant that controls how much a car speeds up or slows down by if6 Q6 O: h5 `* M. K
;; it is to accelerate or decelerate M2 U" ^, o, o: r6 }
phase ;; keeps track of the phase* Z* p" O) W: m+ X% ^" b! R% N
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 w- l+ m" R& k- y current-light ;; the currently selected light* Y+ m6 n: G# P# D3 a! f
5 x( o0 g+ x: N0 ] ;; patch agentsets
: T" `8 f* A5 J4 y intersections ;; agentset containing the patches that are intersections0 y$ h4 o8 w) Y; u, K) J7 H
roads ;; agentset containing the patches that are roads, b. v! S0 F- |# f5 Y
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/ Z6 Z: U& M+ [% {2 l! a2 `turtles-own
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speed ;; the speed of the turtle
: i' x/ P. M' a$ n# ?9 } up-car? ;; true if the turtle moves downwards and false if it moves to the right
. q8 v6 t* V7 B wait-time ;; the amount of time since the last time a turtle has moved
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( r& V; s2 O' U }patches-own! ?) d, {" Z. m8 o! a8 x0 o
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intersection? ;; true if the patch is at the intersection of two roads$ h. F U" Y& T y8 K
green-light-up? ;; true if the green light is above the intersection. otherwise, false.' |/ a& q9 S$ B8 `/ w6 ?0 Y
;; false for a non-intersection patches.
. q; b2 U2 T+ W4 @ my-row ;; the row of the intersection counting from the upper left corner of the
% B8 i. V4 K- w7 I ;; world. -1 for non-intersection patches.
% b: O+ k" u2 j my-column ;; the column of the intersection counting from the upper left corner of the/ P) o! y9 r3 o6 S, H
;; world. -1 for non-intersection patches.2 ^& B. Y. V) s2 z
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 d8 b- V! [0 v2 K- ]+ ]4 A0 b auto? ;; whether or not this intersection will switch automatically.
6 q/ s: d5 q2 ]0 o1 b ;; false for non-intersection patches.9 w0 c- J" ?( W" B, J7 l; n- y8 p
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;;;;;;;;;;;;;;;;;;;;;;
* ^& D; y+ P0 M2 B8 I* [& K;; Setup Procedures ;;& `3 e7 K- {% g! o% L0 i
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+ X% D `1 Q+ o+ v* H;; Initialize the display by giving the global and patch variables initial values.* a# {8 Q+ B- Y8 q, U0 g1 v
;; Create num-cars of turtles if there are enough road patches for one turtle to* Y, V; s/ t3 ]5 k& U
;; be created per road patch. Set up the plots.8 \- J, |# R; A' B$ o' e, O' O
to setup% u; t: o9 A- |0 v
ca
9 E7 F2 q1 N( u! V setup-globals
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) i) M; E( p: c* u8 l$ [6 w ;; First we ask the patches to draw themselves and set up a few variables* u0 G7 X' A4 A% W" U
setup-patches
% \ x2 w" j- Q2 F* g7 Z make-current one-of intersections" {0 N, m5 r. v1 i! m7 ?
label-current
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set-default-shape turtles "car"
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2 K! X {7 N/ G1 G# B2 S if (num-cars > count roads)
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' [3 x/ w) ?! `4 e user-message (word "There are too many cars for the amount of "
" G" K# b+ Y4 o+ ]' X9 Q "road. Either increase the amount of roads "
* ^4 l0 ^1 |# y5 u: R' i "by increasing the GRID-SIZE-X or ", K& w4 Q3 P. {( i
"GRID-SIZE-Y sliders, or decrease the "0 I; P" ]8 p6 v
"number of cars by lowering the NUMBER slider.\n"& _4 c/ J4 U1 A' i
"The setup has stopped."), P& Z* t5 o+ N
stop) A! w0 B4 J& k
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: F @4 M! V7 v* W/ A( R% x% ~ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color7 I5 J6 D( a5 d5 l) `
crt num-cars
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setup-cars
1 Q7 H4 J/ y7 U6 v5 a0 X" m. v- d; _ set-car-color
+ c6 R9 w+ Q9 s F$ \2 b record-data
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1 }# y1 J* d5 b2 t# e g8 D ;; give the turtles an initial speed4 z- E6 N p8 i8 ^: z# B% u7 y
ask turtles [ set-car-speed ]) x" N1 N- ]5 U
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reset-ticks- a# r4 }3 n# L% [) |5 F' S
end6 m0 N2 s3 `9 r- ^
' B, ~+ e1 q8 V& M* w;; Initialize the global variables to appropriate values4 p5 n* }& y/ i1 g7 t$ W0 h8 c- P9 x# U
to setup-globals
$ y; ^" W/ S/ `. D) l( }9 Y set current-light nobody ;; just for now, since there are no lights yet( X1 G( Y# u1 }# O" r. Y9 z
set phase 02 S, J5 d" p( f# {) ^% p
set num-cars-stopped 0# r" X) l8 L& U F7 z
set grid-x-inc world-width / grid-size-x
/ S# p7 c* G- V( T& E- X& _! |7 q' ~ set grid-y-inc world-height / grid-size-y/ g9 `! z( Z: s: \3 X3 G9 ?
1 b9 i$ |! H" h7 C) z4 D ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
0 O: w- U }9 H& l( Q5 t4 m5 f set acceleration 0.099
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% p3 F8 r T$ F& ?) F;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) \6 E0 w1 Q f0 b% \9 w/ O: N
;; and initialize the traffic lights to one setting
% g6 D# V, E* P% L+ [: Y$ o1 Tto setup-patches
7 H' V# G2 }: O( p' t! i+ |+ ~ ;; initialize the patch-owned variables and color the patches to a base-color
: k9 U$ R) ^& i5 ]: b" g1 d ask patches2 B. @( c( z. s4 j7 O
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$ u4 H$ ]- Q" C d" F4 D/ L! x# } set intersection? false
6 g$ l8 w. Q6 N9 M set auto? false
$ z3 ]3 l0 E+ R1 T& C5 o set green-light-up? true, Q8 c$ Y. z" S& r8 N2 [: M, m
set my-row -1
; ]2 D! T# [( Y; ^- }$ t8 y set my-column -1
6 J- l6 ]$ `- H. ?) M- d set my-phase -1
2 r( H% [0 ]5 o0 V1 h# ?$ @ set pcolor brown + 32 m0 [: {: _6 D! `1 j% ^. |
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. \6 D# A* g5 X0 {+ x! z) r7 e ;; initialize the global variables that hold patch agentsets
0 a# v: M# h I set roads patches with
$ z* @/ `$ R+ b3 s R' X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) X5 A9 ?; c! N6 n$ F
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]* `3 \: u$ d. O( ^; t k' x
set intersections roads with3 i( _# A/ r8 E9 p1 `1 v; P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and- M% W S- J* E- v2 \
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]) _6 \0 G# h/ A. v/ o5 x/ f; u
setup-intersections2 I' D8 a' s3 Y1 ^. v- l0 w
end
- @0 T5 m: e' Y' V" M; @8 R6 s0 e其中定义道路的句子,如下所示,是什么意思啊?
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, H2 Q: \$ M) f5 a: B [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 P" r( G2 ?" P# }% t2 Q5 a (floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 N( L; z6 B+ p; m$ _! d3 x2 ~
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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