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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。
# M# ~% c% h" N: G9 a, f# i/ B9 Cnetlogo自带的social science--traffic grid这一例子当中,8 _$ Y3 T" X( c
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction6 x6 I4 n4 y! u' n% A7 j( Y7 l: I
grid-y-inc ;; the amount of patches in between two roads in the y direction: g; j3 t0 ^: ^- P# o; A, j
acceleration ;; the constant that controls how much a car speeds up or slows down by if
: h. t0 w" O& F) f# Y- I ;; it is to accelerate or decelerate
3 j: u: p4 c2 J, I7 X" `! ~ phase ;; keeps track of the phase
w: k2 B: J4 N9 i n% [ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
0 {7 p0 ?4 \3 @7 d) g8 J current-light ;; the currently selected light
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;; patch agentsets, W6 q0 d r" | T. R- m [
intersections ;; agentset containing the patches that are intersections" ^, j' j( M5 ~- p7 n2 y, W: r
roads ;; agentset containing the patches that are roads6 }& w4 e7 k6 b5 U
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turtles-own
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speed ;; the speed of the turtle/ _, W* M0 O3 e1 a" M% u7 |
up-car? ;; true if the turtle moves downwards and false if it moves to the right
, z$ f. T( b q. i; L% V wait-time ;; the amount of time since the last time a turtle has moved+ c; N) t/ z! C* D
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patches-own& T3 _. _3 H9 b+ v7 \' G( P
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intersection? ;; true if the patch is at the intersection of two roads1 w X- |( b1 I" l# M; Z
green-light-up? ;; true if the green light is above the intersection. otherwise, false.* n1 U& C K' A, O5 N" A# e
;; false for a non-intersection patches.$ R6 e' t& U7 Z& q# T# A- j) z2 A
my-row ;; the row of the intersection counting from the upper left corner of the8 x+ b1 G$ q n9 I* }, K( k2 J* V9 K
;; world. -1 for non-intersection patches.
1 u0 s8 ]/ A* k/ K# K my-column ;; the column of the intersection counting from the upper left corner of the6 ^: P) K8 x9 c6 {6 D
;; world. -1 for non-intersection patches.
# j+ a# l7 n9 S: e! u0 K my-phase ;; the phase for the intersection. -1 for non-intersection patches.& R# s% u- O$ J! o8 R
auto? ;; whether or not this intersection will switch automatically.
3 u, Q6 k b" @6 o ;; false for non-intersection patches.
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' t, @$ P7 v5 ^$ X3 P- n;;;;;;;;;;;;;;;;;;;;;;( y6 F# n% z5 e9 I7 n7 Y1 U2 D
;; Setup Procedures ;;7 O- m# w8 }7 e6 F, Y5 |( W
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8 Z$ ~; F; D$ a A! [& b;; Initialize the display by giving the global and patch variables initial values.5 x6 Z* r0 k+ f1 _
;; Create num-cars of turtles if there are enough road patches for one turtle to
) B7 h- u( N: R* o;; be created per road patch. Set up the plots.
8 _- e O% d! S. [& G6 @to setup
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& o0 u+ u& u7 C$ V. @: I setup-globals1 h+ z2 `0 W! L$ ]% A
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;; First we ask the patches to draw themselves and set up a few variables9 R6 I/ N$ b- ^) }
setup-patches! G1 i5 H- y' h. }, v3 A
make-current one-of intersections
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2 F" y/ U& a4 ~/ z P set-default-shape turtles "car"+ N% h6 o K* B, s4 j5 l
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if (num-cars > count roads)" b h1 d5 x m/ S
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user-message (word "There are too many cars for the amount of "9 K4 Q7 v- ^2 g
"road. Either increase the amount of roads "
J; z w4 o& |2 P* B3 Y, o f "by increasing the GRID-SIZE-X or "
" q5 P0 Z/ ]: L "GRID-SIZE-Y sliders, or decrease the "6 w! V! ?, G" @ a
"number of cars by lowering the NUMBER slider.\n"
5 i0 D9 b& N$ ?& D' }- P "The setup has stopped.")
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+ x* c" j5 H$ w @+ w ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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setup-cars
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record-data
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;; give the turtles an initial speed
' F0 j. O. Z: z: i ask turtles [ set-car-speed ]
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reset-ticks- c9 ?1 L' a7 \. y" o* G
end
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7 O8 G7 u# l0 c;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet. c; r+ v& @" i3 u' ^0 s- R; L9 s
set phase 0
& z) N' i" ~0 [3 L" } set num-cars-stopped 0 S5 W! w/ U; n& ]7 a1 x+ j% b
set grid-x-inc world-width / grid-size-x4 B; n' m" H' i5 @9 W
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' c3 E5 s2 o' T' d, M
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
. K- W! c: |7 A5 V;; and initialize the traffic lights to one setting
1 v9 a1 x( f2 y ]+ X! T; v- gto setup-patches
& _7 F1 ~) V" Y8 q+ p ;; initialize the patch-owned variables and color the patches to a base-color L/ w- Y. u( k0 ]
ask patches. x& {: ~0 C' X1 t$ T
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set intersection? false
3 g, \4 {$ U3 g set auto? false
/ B! }9 F4 v- |# d set green-light-up? true
2 `. C! J: B) k% ?+ H- @9 o set my-row -1
6 A1 x. B2 k$ C' R) Z$ g9 Q set my-column -1( N$ O' ~$ J* K" B: j
set my-phase -1
1 [" ? P, f, A9 @ set pcolor brown + 3
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, C0 v4 F7 F _' m7 S8 P ;; initialize the global variables that hold patch agentsets# p* a5 K. N) D' N
set roads patches with
0 ?8 s4 X" |) \3 S$ z1 e [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or ?: f, K% `* W) y. K: ~6 _- U
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: L" c$ V, X" f set intersections roads with
4 Y* x3 u0 S; X3 F; u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
. B8 P0 a& ?& j, ^2 o9 ] (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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& P. {- ^% u2 {- ^ Y2 G9 P! r$ ` ask roads [ set pcolor white ]
1 R4 ~2 S4 X$ H+ S# } setup-intersections3 x! r4 ~8 `# S. s& m* P" o |
end" M$ I! u5 K2 J6 O7 ?# f. ~6 ~" c
其中定义道路的句子,如下所示,是什么意思啊?
7 W+ @: I+ d8 t1 U, s& g set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ M, H8 U$ ~/ {: z$ i
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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