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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。
- @) X; z5 _5 x6 r, l- c4 M. Enetlogo自带的social science--traffic grid这一例子当中,
: v1 L) u# Q; G7 A. Xglobals
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. P9 z. w3 m5 H" h7 K v grid-x-inc ;; the amount of patches in between two roads in the x direction
/ A! W& L* l; q" h( j# b# ]5 G grid-y-inc ;; the amount of patches in between two roads in the y direction' ~. W& Y- o7 R* b3 T6 B) Q d
acceleration ;; the constant that controls how much a car speeds up or slows down by if7 s& |( I- M/ Z- L, l# Q
;; it is to accelerate or decelerate& P- f3 y+ J/ \- x) z4 H
phase ;; keeps track of the phase+ J' U( q9 p. y4 O1 d9 S* k/ k, g
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure) k& \4 l5 i$ k- m H
current-light ;; the currently selected light/ U+ i8 |, R5 [- y" A3 l7 b
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;; patch agentsets
. T! K8 |/ P0 A# a3 u5 Y intersections ;; agentset containing the patches that are intersections
9 W9 G3 X; h# g+ @9 G: N) ~ roads ;; agentset containing the patches that are roads! L& K! |8 Q, ]
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turtles-own
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speed ;; the speed of the turtle6 S8 l: N+ |8 M/ M9 R
up-car? ;; true if the turtle moves downwards and false if it moves to the right+ D. t! X1 ]* {
wait-time ;; the amount of time since the last time a turtle has moved3 G9 l# a& `5 Y- N
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patches-own
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& @! L, d( N1 v6 p) @4 A+ S9 ~3 t intersection? ;; true if the patch is at the intersection of two roads2 r* `; v! L- X4 v/ ]/ v" h) l; \
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
7 Q3 F8 E0 f# e' Y0 ?* b; k3 f ;; false for a non-intersection patches.
! O, c6 a9 J- H- }4 n/ j/ r my-row ;; the row of the intersection counting from the upper left corner of the
& M# s3 R% b/ M ;; world. -1 for non-intersection patches.0 n& u# u, V, P( v
my-column ;; the column of the intersection counting from the upper left corner of the8 T U6 }- d/ v% d% H" D
;; world. -1 for non-intersection patches.# L8 k0 q8 G1 A X1 @% _! C" Y- e
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
6 l7 [0 @/ P2 G1 [8 D auto? ;; whether or not this intersection will switch automatically.9 `! y* m/ [) a# {: i
;; false for non-intersection patches., e( I0 r' d& {; G
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;;;;;;;;;;;;;;;;;;;;;;
1 V3 H9 `# t4 E! _. |8 J. V;; Setup Procedures ;;9 H+ |% K' C# w, I8 k1 O& k+ b
;;;;;;;;;;;;;;;;;;;;;;4 v& V2 D% ]5 \
4 T8 G( G2 Y: L;; Initialize the display by giving the global and patch variables initial values.+ s% t7 m) B5 n, ]- ?/ w; R! m
;; Create num-cars of turtles if there are enough road patches for one turtle to
8 S) H7 G; h" {1 i;; be created per road patch. Set up the plots.
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setup-globals$ g' R+ Y# O1 s2 R
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;; First we ask the patches to draw themselves and set up a few variables9 A5 e( {) N: ?4 C4 y
setup-patches% l& o. n5 i; _0 w8 @2 X
make-current one-of intersections
1 ^4 Q* n" r9 d" ]! a label-current
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+ i& o4 b$ m6 I" b8 J9 Q; ` 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 "
. V. J. H) e1 ~( z7 G- X! G4 a "road. Either increase the amount of roads "
8 l7 y$ a7 w9 |* [: W7 I8 I( u1 m6 d "by increasing the GRID-SIZE-X or "
: v3 Y& C+ g! N- i: E! ]# W "GRID-SIZE-Y sliders, or decrease the "! x9 s4 j: I$ o
"number of cars by lowering the NUMBER slider.\n"% w6 B5 L- f6 m: A1 i
"The setup has stopped.")
8 P- N" @; B5 }8 i; S3 X stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
* H' \" k1 f! w% n crt num-cars [: S F2 P# t4 u+ V0 B" r- |7 z
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setup-cars
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record-data
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;; give the turtles an initial speed! F) R! {0 b# }& Q
ask turtles [ set-car-speed ]6 x$ Y$ Q6 Y S0 l: V6 o" L; @2 e
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reset-ticks+ l# F& {% Y; {' s
end3 Y2 W& j, {/ T; I
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;; Initialize the global variables to appropriate values
, L# Y5 a0 ^3 vto setup-globals$ k4 W6 Y* A: W" L" F
set current-light nobody ;; just for now, since there are no lights yet7 R1 Q- F9 P& Q$ G+ P' U! a- f
set phase 0
" e3 l3 s& U0 k set num-cars-stopped 04 x, K: l, v) R% f: P1 a) s5 ~5 I
set grid-x-inc world-width / grid-size-x
- w4 N, L' |& Q! Z set grid-y-inc world-height / grid-size-y
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+ |8 o! n l4 i. U ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
1 K7 u6 Y$ d: Y4 ^2 g+ N# b% ` set acceleration 0.099% P" {; J6 `4 v3 q! x+ P6 c
end: K% z) y j( t8 {! x" P- p8 b3 r
# d0 u) H8 [$ y) |7 F;; Make the patches have appropriate colors, set up the roads and intersections agentsets,) Z& ~3 N$ i6 Q+ P
;; and initialize the traffic lights to one setting- l$ E% r& ^4 z
to setup-patches# G3 E; @) ?& P8 u, t
;; initialize the patch-owned variables and color the patches to a base-color
6 @; h9 I" l+ L ask patches
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set intersection? false- o) G' O( V8 Y
set auto? false& ^4 H6 u. g+ Y% @8 Z
set green-light-up? true
$ H& g1 B% a8 N$ }( H. k set my-row -1
8 g. u. G9 B6 d( B1 E5 o& H set my-column -1
' y" w% Q) [$ b( o2 E set my-phase -1' ^) O) J6 D, c) U x* m: j
set pcolor brown + 3
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' C- l# e* X% W d# N1 ] ;; initialize the global variables that hold patch agentsets
" B9 v" p2 i* D9 Y1 N set roads patches with, L7 f2 H; ^9 q; a0 U1 |
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ ?) W8 f# U1 [: _# ]
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; a+ w J# D! L# V; W0 q( i set intersections roads with8 j/ r& C3 x0 n: ]% j I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and( i9 L/ W* t/ K& H% w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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' Z+ [* d; n0 i* s ask roads [ set pcolor white ]
?1 D5 g0 o" E: \% W setup-intersections3 {( ^' }6 G, _- q% _5 h. c
end% ^7 ~: K( P, W9 z* Y7 |
其中定义道路的句子,如下所示,是什么意思啊?
7 q5 T. N, n4 H2 \; K6 a! P set roads patches with
* l8 D4 M! R# t8 V# W [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or( S+ l2 v0 m! R! C$ D8 n9 ~
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. y8 W: T0 F# t8 G/ m$ Z+ t; _7 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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