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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。: u0 {. I( C' k( d' o2 \
netlogo自带的social science--traffic grid这一例子当中,
& C/ |4 }. e6 p/ Zglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
7 a; Q0 J" e- I4 W grid-y-inc ;; the amount of patches in between two roads in the y direction
' K& F7 a! x7 | h Y acceleration ;; the constant that controls how much a car speeds up or slows down by if. o& i& V8 O; V% L1 h
;; it is to accelerate or decelerate
5 p2 {0 M3 b! e' s phase ;; keeps track of the phase
! L( U4 B- x& {2 R7 v num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
2 s C& R) `; x+ A2 I$ ]) P current-light ;; the currently selected light
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;; patch agentsets
0 k) N2 V. B6 n: Z; T3 `9 U intersections ;; agentset containing the patches that are intersections
3 h; P7 z* p, S# _& P roads ;; agentset containing the patches that are roads
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turtles-own# y4 E1 ?" b( t$ W, N
[
3 D! E3 J4 r: [0 @! @ speed ;; the speed of the turtle6 ]. k( I) v4 y9 _& W
up-car? ;; true if the turtle moves downwards and false if it moves to the right
; E& W# O9 }: k: O$ c% G8 \9 G wait-time ;; the amount of time since the last time a turtle has moved
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patches-own% ~. ]- X1 S/ W6 h% i7 c: o; H, ~+ p
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`* g; }. n" n5 U intersection? ;; true if the patch is at the intersection of two roads8 g- f- E8 b3 p
green-light-up? ;; true if the green light is above the intersection. otherwise, false." n b3 O( F4 A; t% U
;; false for a non-intersection patches.
' Q# T' V# f; t8 Y my-row ;; the row of the intersection counting from the upper left corner of the
0 N, q3 ^1 h! ~0 q# m# E ;; world. -1 for non-intersection patches.
5 {# I. u0 c8 N6 [% A. \2 O% ~/ c my-column ;; the column of the intersection counting from the upper left corner of the
@0 O' f1 i! X3 B$ z) X ;; world. -1 for non-intersection patches.4 q! ^, `# p+ a
my-phase ;; the phase for the intersection. -1 for non-intersection patches.3 z" [+ ~. w; U- r
auto? ;; whether or not this intersection will switch automatically.
* |( w. Y/ R" {# \" [5 r1 [+ L ;; false for non-intersection patches./ \, |+ i$ K4 }0 Q4 s$ E" ?
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;;;;;;;;;;;;;;;;;;;;;;0 E! G0 {: `' w
;; Setup Procedures ;;
+ S0 e4 q% L3 w;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.! n \7 h9 J3 c' r4 P# r
;; Create num-cars of turtles if there are enough road patches for one turtle to
6 ^1 n0 x8 S! p' a m;; be created per road patch. Set up the plots.3 z- |# T. T# p
to setup! m+ z2 w7 W; \+ a
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
3 i+ s( @) K; H7 @' v" g ~ setup-patches, x& ^' g$ P8 [$ F4 F6 g/ R {
make-current one-of intersections0 \/ D( L; Q/ d$ r! W; {+ H
label-current' s4 V% }3 A& I2 K
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set-default-shape turtles "car"
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2 Y9 Z/ G% e: n; { if (num-cars > count roads): }7 M7 r. s3 n7 q
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user-message (word "There are too many cars for the amount of "
: R' y. i! X8 c+ D: i: j) Y "road. Either increase the amount of roads "
0 l" R: f; I5 S/ N- s "by increasing the GRID-SIZE-X or "
, _6 v2 n% h9 A "GRID-SIZE-Y sliders, or decrease the "5 j" e% R5 s/ N7 a0 g
"number of cars by lowering the NUMBER slider.\n"3 q7 K( q; P5 W+ W" E% G9 F- f* n
"The setup has stopped.")! z4 l+ {- ~+ T0 B: ~" b. ?
stop& n) P9 v$ |( I9 l) d. X5 N" \
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3 N% r6 n/ J) x; ~ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color3 U8 P4 u4 N. X) B3 l
crt num-cars
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setup-cars
7 Y$ B# C8 Z: k& o X4 f set-car-color
, Z. O' _& \8 B record-data
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& ~! Q- v$ _! g1 T3 D1 a ;; give the turtles an initial speed
1 R% V) n' J& ^" |$ u3 o/ B: H ask turtles [ set-car-speed ]/ K N% d% I( z% h& g; w+ J
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reset-ticks1 E, Z& G; m& o
end% D, z2 k, S" Y- k- a+ o
. ^2 n. A: e, g ^6 b: x;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet
5 B5 C/ i: Q# z7 \# Z: J8 q set phase 0
4 M9 X$ t0 ?0 ? u( E# W set num-cars-stopped 0
0 q+ Z8 e2 Q- g3 Q# i set grid-x-inc world-width / grid-size-x
2 m& E8 K4 W% T0 y' g$ w b 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
1 ^! M9 B: L# y- c4 d5 ] set acceleration 0.099, J# U% l+ a0 X6 r
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' U+ _' f1 B5 U5 V1 s;; and initialize the traffic lights to one setting
- u4 M7 s: G- {2 U/ A) Kto setup-patches
: `7 ?& X+ L2 `- }1 f ;; initialize the patch-owned variables and color the patches to a base-color
9 k" C# c/ {; } ask patches0 H8 }0 B9 x( O b% a
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set intersection? false
( A( P$ J( }( E9 _+ J+ o1 d set auto? false
# t& n; d1 {* t. v3 A set green-light-up? true
6 r! D) z. O2 M3 k set my-row -1
3 o0 R/ m \! h set my-column -1
: O( N6 s: B/ X" c/ m set my-phase -1+ _+ j( Q7 S N0 b
set pcolor brown + 3, X2 k& g+ W& E! t
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;; initialize the global variables that hold patch agentsets
/ [/ p! t' ^3 B; q set roads patches with& T' Q8 \0 F( ^- Y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- i& B5 s; G3 j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* M1 ]& g |/ }4 m$ B
set intersections roads with: h. g# K' F! j# q1 v# K; J9 o" B
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and' Z: \3 w3 S3 O+ U& m0 x
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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5 O. J8 b% @- j1 i ask roads [ set pcolor white ]9 x. o }; Q9 I2 _
setup-intersections
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4 d4 x; g7 A& c. k; z5 V其中定义道路的句子,如下所示,是什么意思啊?3 K" \( B- W. V, ]% {# ^
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& Z4 A/ O$ `1 Q2 E% \" 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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