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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。# Q; K% I! a, I, Q
netlogo自带的social science--traffic grid这一例子当中,
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grid-x-inc ;; the amount of patches in between two roads in the x direction( K+ A) {8 e4 n" q. H
grid-y-inc ;; the amount of patches in between two roads in the y direction9 i% V* l8 l6 ^5 N9 e: h
acceleration ;; the constant that controls how much a car speeds up or slows down by if) G `; t ~1 `. O" s1 [
;; it is to accelerate or decelerate
b* d, \0 |+ p2 [9 R& y phase ;; keeps track of the phase, n+ c5 L: m7 A; l# @+ @
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
# _2 X/ i% B8 E H current-light ;; the currently selected light* z$ v8 {4 c+ C- p$ M4 t3 I1 L' i- V
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;; patch agentsets
) t. _2 h# }. s7 A& C intersections ;; agentset containing the patches that are intersections% j1 b, i# I1 K0 e1 j
roads ;; agentset containing the patches that are roads1 n9 Q2 b# S6 N- w" W
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turtles-own
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speed ;; the speed of the turtle
% M4 b9 Y0 J8 J* T/ _ | up-car? ;; true if the turtle moves downwards and false if it moves to the right1 S; |& d Z/ G1 W# f E7 E
wait-time ;; the amount of time since the last time a turtle has moved
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: E8 F4 a* z$ {. ~0 M* opatches-own0 U3 I9 k& h) U
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! y% {% z. R" u intersection? ;; true if the patch is at the intersection of two roads
- v" L# |9 m U6 p2 Q green-light-up? ;; true if the green light is above the intersection. otherwise, false.( h3 o) x) ?3 K: C4 |7 @
;; false for a non-intersection patches.
% r! }5 b, M) s1 e3 o9 M3 @5 | my-row ;; the row of the intersection counting from the upper left corner of the
6 G; @& C- p4 r; I: a5 g+ t ;; world. -1 for non-intersection patches.
* N, k' Y# K/ e9 p* N) |! z; z my-column ;; the column of the intersection counting from the upper left corner of the
' l, k3 e! s# X8 ?+ Y ;; world. -1 for non-intersection patches.
$ j+ |* l$ A6 G' [ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
1 _7 @% D$ T# C5 q8 n! U0 H6 W auto? ;; whether or not this intersection will switch automatically.
: ?% @+ ^! o3 x, p* j' C* C ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
' C4 d2 r; o/ @8 T: }6 o/ \;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.
2 Q# E# J7 A( ]/ n;; Create num-cars of turtles if there are enough road patches for one turtle to8 z0 Y; J! a/ T3 U+ a
;; be created per road patch. Set up the plots.& A' J9 {8 J3 }$ h0 [' {
to setup
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- b2 q6 m. P: z% N ;; First we ask the patches to draw themselves and set up a few variables
0 v8 }: P; T' e* ~% Q setup-patches( s1 t: s" X/ b, n
make-current one-of intersections
# k! K W4 j6 K) ^& U4 w% U; ? label-current
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set-default-shape turtles "car"2 [* j1 H. X2 j8 F% H5 E
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if (num-cars > count roads)
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' |; V; d! B1 G* \4 i. _2 N9 k user-message (word "There are too many cars for the amount of "
, B6 F8 N+ h9 F "road. Either increase the amount of roads "
1 b5 T3 `. {' b- k& l "by increasing the GRID-SIZE-X or "
H7 W4 Y4 E' \3 P4 f "GRID-SIZE-Y sliders, or decrease the "& V% u$ R& @; O; o# ~( x2 b
"number of cars by lowering the NUMBER slider.\n"$ M" Z! l y' s5 s8 b! w
"The setup has stopped.")
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l* x/ |: y8 L% t5 z; S7 | ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, @+ J5 y9 q: K crt num-cars
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setup-cars
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record-data$ p( r+ J) K; d* y4 F9 ~( Z0 p( T
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' v( O' E: O. F2 | ;; give the turtles an initial speed$ l- J+ B' ?8 e% i" M$ G; z
ask turtles [ set-car-speed ]0 a. C( t8 U! ?! e1 Y
# P4 B' g9 V3 _" G% Q l reset-ticks
! ^5 d8 \, u2 A$ V8 m. A- Vend
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;; Initialize the global variables to appropriate values1 A& ~1 [% ^* B7 h* o8 j3 {
to setup-globals9 N! u7 @8 R7 L( Y1 }
set current-light nobody ;; just for now, since there are no lights yet
7 o0 `: w1 s& `. Y% b% X set phase 0$ d6 ~8 W& Y# j1 _: w
set num-cars-stopped 0
& I a6 j2 X2 R set grid-x-inc world-width / grid-size-x
4 K' r1 ?5 w" {. S6 W' e% K set grid-y-inc world-height / grid-size-y5 e( i" ^! t2 @; H
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
0 Q' x8 ]' K" u1 |' a) \ _+ k set acceleration 0.0997 G5 H1 m, _" b/ Q, O0 U
end" g5 b$ K# {0 k( h
- P+ G2 N' Y0 o" [' j;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
( c9 y, W: I6 o;; and initialize the traffic lights to one setting
- a& U+ n3 N3 h) sto setup-patches& ]% }5 p$ Z F% }8 A+ r
;; initialize the patch-owned variables and color the patches to a base-color
$ E# P- y q( d7 [! B ask patches/ I" a" x# s6 ]7 d5 x
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set intersection? false
' O8 q4 O0 ]6 c: \$ R7 c9 W set auto? false
2 O7 ?: R2 o0 k8 X& E set green-light-up? true
1 D6 Z; n+ t( K+ V s& j$ C set my-row -1
0 F& Y5 k1 C0 A# j4 ~ set my-column -1
) F0 N+ X' \% d% [. b. j8 Y set my-phase -1
) T9 y+ k0 p1 q# _, J4 _+ P set pcolor brown + 3
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: x- c" }: S. m7 v5 w ;; initialize the global variables that hold patch agentsets; W7 s d" M9 ~ X
set roads patches with# o8 _- B7 E( ]3 j( s7 r
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. h$ y/ J* K9 d9 B, p2 P7 E
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. j8 t. m( j1 i* Y! x; u set intersections roads with
; O; v) j. d- g n0 b* |2 n [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
2 L6 ~- G( o @) v8 t; }, p# Q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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* W7 m0 F1 r7 `) U) f ask roads [ set pcolor white ]2 u' \2 J6 h0 H. w
setup-intersections
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; S4 B+ V9 ^- g7 I8 {其中定义道路的句子,如下所示,是什么意思啊?
5 ]/ `4 U$ }5 c$ v, h, e+ J set roads patches with! H( x9 i' s6 Q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. d' t. b$ d9 p. d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) T+ M1 w8 O1 C1 A- ?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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