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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。; w7 s1 f( s% h& Z: \ _, \5 ~
netlogo自带的social science--traffic grid这一例子当中," S) ~9 O: t+ \3 W- u( t4 |/ t$ e, v
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
- f% P) a) g1 I* W grid-y-inc ;; the amount of patches in between two roads in the y direction
$ Z* ?5 ~, M) {0 Y' `$ e& p acceleration ;; the constant that controls how much a car speeds up or slows down by if
) x, _' L" y! z' }% o* }( C! x ;; it is to accelerate or decelerate; {: j4 @2 }$ {
phase ;; keeps track of the phase
3 T# c6 R) P% v7 i s num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure/ S/ D4 r) `! p) Z$ F' G
current-light ;; the currently selected light; B$ C# C& \- \6 y: o1 ]& W% A( b7 j
$ y% ~9 B; K! _& g ;; patch agentsets3 I1 _) d8 {1 ~; n5 F
intersections ;; agentset containing the patches that are intersections0 q, V* E' a* I0 {$ R
roads ;; agentset containing the patches that are roads( \* q* B4 A8 R( s
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- C3 ?" O/ D, a2 n2 ]* ^% k5 v0 p* c3 Iturtles-own# U! V b( L' x
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" p* p& W, F* I l$ X. i speed ;; the speed of the turtle) Q+ \$ u2 f4 T2 Z" H! |
up-car? ;; true if the turtle moves downwards and false if it moves to the right
' p2 `" v# y& W, E8 y8 \1 u wait-time ;; the amount of time since the last time a turtle has moved
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! A5 o2 u9 u( T1 ?+ C7 |2 m: Z- Upatches-own2 [5 Q [3 o6 ?2 x+ |2 T
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intersection? ;; true if the patch is at the intersection of two roads
3 w- T3 _: f* o2 c3 Y2 _6 j" o green-light-up? ;; true if the green light is above the intersection. otherwise, false.( Y; v9 ~! X( c4 N
;; false for a non-intersection patches.
- a, M4 P" X; ~; O* U. H4 a) W8 \) d my-row ;; the row of the intersection counting from the upper left corner of the A% }3 F, o% C8 \1 \* }9 @
;; world. -1 for non-intersection patches.; C# O* O' b3 J8 w) j
my-column ;; the column of the intersection counting from the upper left corner of the
8 }, C# R% j! n7 d. | ;; world. -1 for non-intersection patches.( y- E3 j8 d# I5 m$ B
my-phase ;; the phase for the intersection. -1 for non-intersection patches.* R0 A! p, w& t1 W! |6 B9 A
auto? ;; whether or not this intersection will switch automatically.
+ A4 t* @0 c5 ?/ Y8 w ;; false for non-intersection patches.4 B/ r; t! {' E& i2 u, m0 Q
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1 D4 }/ e2 ^$ b4 X7 P, };;;;;;;;;;;;;;;;;;;;;;8 }' v) C% M( q) |2 Z# A' c
;; Setup Procedures ;;
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' p4 y' g& ]& I;; Initialize the display by giving the global and patch variables initial values.
7 m# V0 H' z2 o. \' z;; Create num-cars of turtles if there are enough road patches for one turtle to4 P3 s7 P/ S! u; n% G0 o' Q0 K
;; be created per road patch. Set up the plots." E% G, }4 W7 c% }! n
to setup) [& `, G4 \8 i
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
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make-current one-of intersections- s6 N$ |' P/ \* v2 [" o2 v
label-current a5 n$ {7 d9 W# G" _* t& u+ w
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set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "6 \9 D* L+ C8 M8 d1 c
"road. Either increase the amount of roads ". p0 A" y" M1 m( L8 ~$ u
"by increasing the GRID-SIZE-X or "
' ^9 |7 d3 Y* A0 f2 F; ~ "GRID-SIZE-Y sliders, or decrease the ". s) w2 ?. d x a
"number of cars by lowering the NUMBER slider.\n"
+ D7 a1 e3 z; X- b8 L+ A "The setup has stopped."), W& t f& o) @6 {
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, E7 ]4 P5 X) I, [
crt num-cars0 @' h& ]; T6 ~" Q
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setup-cars
, [' z" C. [5 L8 s set-car-color
! \, N8 K1 k4 |: U; \/ q record-data
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;; give the turtles an initial speed
2 T* ]# |9 `* s9 m' K ask turtles [ set-car-speed ]' Y4 T5 Y3 O$ z t) u
4 C" t1 z* j" g: u: g8 } reset-ticks
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;; Initialize the global variables to appropriate values4 Y2 g# T7 k8 x
to setup-globals3 O/ T& d. M& f; E' p9 w" W/ n) E1 i
set current-light nobody ;; just for now, since there are no lights yet- U2 a' }0 k2 L/ q, ]! M
set phase 0. e! e S+ N) c3 s" u, {
set num-cars-stopped 0. g; K9 ~' ~+ g+ ?* w
set grid-x-inc world-width / grid-size-x4 A ?: H" N" w1 D0 ]; z
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- _+ U) [$ L! b# ?
set acceleration 0.0999 Q& F/ L0 U J6 l1 ~% J
end- s; b# s9 `3 N4 a% o+ ]4 R5 Q
# L: Z5 g$ i% e/ q;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 b& f9 P [2 Q6 K* B% b, P' [
;; and initialize the traffic lights to one setting
. a/ n3 {( ^: J6 Y* g* H( E jto setup-patches7 ]9 _$ w6 }3 U$ u% T8 K
;; initialize the patch-owned variables and color the patches to a base-color
( R+ t h+ E5 f) r/ R# @ ask patches
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( a$ n8 _9 e8 z% t9 D. ]! y" u set intersection? false, d% E1 M* A( \$ Y/ f
set auto? false1 I( d: G W* T* f8 g. t/ U
set green-light-up? true
& N5 P/ `! A. {8 @& ]/ |- ? set my-row -1 c8 A) k8 ?5 y0 \% C8 t+ G" G
set my-column -16 s& N4 R" m9 @3 w3 \0 B& m8 E4 |
set my-phase -1
: I# Z! I4 a$ o+ h. q; [5 G! F set pcolor brown + 3" R2 Z2 u5 N! \! e/ U
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H% b0 G$ c" u0 ?$ G+ W, I( {+ s ;; initialize the global variables that hold patch agentsets
6 N5 }, F. |8 a; y- U set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 I* W* H3 ^: Q6 s7 n: u w
set intersections roads with6 p$ j) j w: V3 P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and* l% X% E% u# ^4 L8 O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 M) I$ r8 @7 _- h! D* W$ D
: `' r4 M+ G- S' X, P ask roads [ set pcolor white ]5 Y+ S3 I [9 I5 Q
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?/ E" Q& E$ E3 B$ o/ k
set roads patches with
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# @/ Z5 \) p6 m7 y (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* u. t" s; M5 W. J! @
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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