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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。
4 U! S: M' Z P: bnetlogo自带的social science--traffic grid这一例子当中,' _6 U1 C* m/ r1 G; k
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction8 P! Y. Z- z% C7 G
grid-y-inc ;; the amount of patches in between two roads in the y direction
. g0 i x4 b+ [. z; Q/ d6 \ acceleration ;; the constant that controls how much a car speeds up or slows down by if; ?: n. L: O5 ~1 L) f- n; f
;; it is to accelerate or decelerate
7 v" L9 U+ |" K+ @$ e phase ;; keeps track of the phase# d' N" i7 Z8 {2 r/ i8 h2 X
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ T |$ i0 ?5 b5 V5 Q# p0 g
current-light ;; the currently selected light5 F; ^; j' D3 f6 p( `( n7 i* I
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;; patch agentsets
# f5 R& o0 ~5 Z8 | intersections ;; agentset containing the patches that are intersections2 ^ S, F9 t* p" C: s; x
roads ;; agentset containing the patches that are roads# f! i" D2 s- I9 E0 I {) s# M$ M
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turtles-own
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speed ;; the speed of the turtle- a% Z, `/ ]0 H* u6 [
up-car? ;; true if the turtle moves downwards and false if it moves to the right% n# O I; `4 e; W& T
wait-time ;; the amount of time since the last time a turtle has moved
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2 O/ B t' Z( o f" \3 [5 |6 Opatches-own+ S! ~4 d5 t* F5 ^4 }
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intersection? ;; true if the patch is at the intersection of two roads" N2 N' C! @& T: I: C: c, n
green-light-up? ;; true if the green light is above the intersection. otherwise, false.) |9 ]+ r1 ]9 C- L2 |" v3 P8 Q& a8 R
;; false for a non-intersection patches.
& B0 C0 P( p$ M& D2 h my-row ;; the row of the intersection counting from the upper left corner of the- `: D' g! k% Y' ?0 ^
;; world. -1 for non-intersection patches.
V1 S; Z5 o- q+ { h my-column ;; the column of the intersection counting from the upper left corner of the/ s1 D, W# L( b5 [, Y# S
;; world. -1 for non-intersection patches.- x% P, L+ T L* T8 q
my-phase ;; the phase for the intersection. -1 for non-intersection patches.* ^: K, ^) Q" `1 F5 L$ `0 V. V0 U
auto? ;; whether or not this intersection will switch automatically.3 E& e B. b3 K/ k- }* u
;; false for non-intersection patches.9 J+ o' J; ]7 p" O! [' @
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;;;;;;;;;;;;;;;;;;;;;;+ o0 ? r1 ^' z' P
;; Setup Procedures ;;
! e- d1 E3 n6 W0 |6 u0 n;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
7 ^% G: {+ O4 @6 I) U- p' V;; Create num-cars of turtles if there are enough road patches for one turtle to
8 U. a) p7 K) Q7 w;; be created per road patch. Set up the plots.8 _, k2 j+ n0 i. w: i% F
to setup, g* [, Y) S3 U) G6 s
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
' U3 v8 t! a* P. D; Q6 O setup-patches
* |2 P/ p, ]+ t8 Q5 T* x1 S make-current one-of intersections
' d3 L% a6 n* K2 r; V N label-current
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0 z5 _' }* h. h3 {* { set-default-shape turtles "car": P; F0 y& T/ S2 K0 h
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if (num-cars > count roads)
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: [3 i" S! R3 M- \( ` user-message (word "There are too many cars for the amount of ". a0 w+ J, M& b9 y1 v
"road. Either increase the amount of roads "! S0 V4 m1 ?9 s; F( f
"by increasing the GRID-SIZE-X or "
0 P; i: P, o/ r& M( H" m# T$ D "GRID-SIZE-Y sliders, or decrease the "
5 T! j. E0 Y, f, O' }# n" z' S "number of cars by lowering the NUMBER slider.\n"
, g: q/ p" d& l$ A; {& D "The setup has stopped.")4 P3 f6 i2 `! K3 K0 Y0 {+ T6 @$ F1 E
stop% o5 F# O1 w) ~6 A* a5 P
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5 ]; v5 l+ q8 |- l1 k ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, Y6 m) _: Q* t I9 }/ h crt num-cars d( {! p* ~" k8 F) X
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setup-cars
+ r/ |+ d1 W' Q p4 B; | set-car-color% A; s# {1 X1 k: M% i9 M
record-data
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;; give the turtles an initial speed
' m* k3 {. g0 }: o8 [& A& h. F ask turtles [ set-car-speed ]4 ?8 I+ ?, h. `
# n: S9 P/ t: q reset-ticks
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, W! j7 n* ^# ~9 a- w, S;; Initialize the global variables to appropriate values6 t' l e9 d6 J
to setup-globals
3 @- y5 Y# w( h$ q C G7 y set current-light nobody ;; just for now, since there are no lights yet& @; s4 v1 D* r/ W1 n/ S
set phase 0! _7 B( P: ^' k- s7 a
set num-cars-stopped 0: f$ ?$ B- t1 H0 b* s
set grid-x-inc world-width / grid-size-x' f' R3 W, e( _1 V$ d. H, Q
set grid-y-inc world-height / grid-size-y
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3 x! Q" h$ U" k ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary8 f1 n5 ] e9 j
set acceleration 0.099, F) R/ d: V7 G# ]( T: Z0 h
end% K6 @) b5 s+ u0 k' Q" b
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
" C# a$ n. a8 i4 C9 d7 A# J;; and initialize the traffic lights to one setting, b" D% Q+ d' C$ U
to setup-patches) K! `# P- v# `+ H2 d
;; initialize the patch-owned variables and color the patches to a base-color% N+ U7 v( e5 O5 ^, W$ z
ask patches0 s8 k/ ]: c( J
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set intersection? false
9 z1 h7 u3 j# y; J set auto? false% l( R; _. t+ ~# b7 q, Q
set green-light-up? true
6 }' O8 [& [/ {% }4 ]3 z set my-row -1
; t$ c: `( k9 ^% U+ p) U set my-column -1
9 [7 Z& E: v7 T+ R set my-phase -14 g+ t- Y& c, ?- e% F5 y, m
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets' E* u7 q, P+ C; A+ D
set roads patches with
0 \9 T3 o/ ]/ h: j [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- C; R( X- _" p0 s3 Y2 k (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. V+ v; l& |7 y) |' s* m0 _ set intersections roads with
# m2 }1 }5 G' D | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
$ d+ ~1 W( `2 w9 ?0 T5 \ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]8 i1 x8 n$ O+ Y6 a6 T
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? v5 M7 u' M, E* s: }: c
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 [0 y2 s) j& T# g, K5 s
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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