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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。
% w: V4 v, z$ ^& ~# @netlogo自带的social science--traffic grid这一例子当中,# d. `) _) J1 L1 x2 R: }0 d
globals6 h( m5 l# R9 j3 \# }
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grid-x-inc ;; the amount of patches in between two roads in the x direction
1 L# R6 h4 I( d grid-y-inc ;; the amount of patches in between two roads in the y direction- H# T9 q9 I) C ^ B
acceleration ;; the constant that controls how much a car speeds up or slows down by if
* h; O# F8 a* S, F ;; it is to accelerate or decelerate# a( a$ j5 n) s1 u2 E* o
phase ;; keeps track of the phase/ ]' O8 B8 v" u& ~# _% g
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure6 P9 b( b6 L% @5 k1 a m
current-light ;; the currently selected light) O7 G& g4 Z% Y/ e* v
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;; patch agentsets
: v/ |/ g' b/ j intersections ;; agentset containing the patches that are intersections
8 B3 X; X( B3 I- l" K roads ;; agentset containing the patches that are roads
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turtles-own
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' c" b9 n# e) O2 i! L$ L6 Z speed ;; the speed of the turtle) b$ {% K0 ?5 r/ m
up-car? ;; true if the turtle moves downwards and false if it moves to the right
2 ~: c) }# C# O H wait-time ;; the amount of time since the last time a turtle has moved3 p& i2 }# [6 L
]
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads3 O7 F- f; h* R6 K8 J2 [
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
9 y+ C, f. Y0 t: S0 b9 T0 w ;; false for a non-intersection patches.! n+ ]. G/ H. ?2 ^+ f6 c
my-row ;; the row of the intersection counting from the upper left corner of the: j9 j7 s/ @! u; s' K! o
;; world. -1 for non-intersection patches.
$ u/ T) g( n$ s2 t) E0 p( ] my-column ;; the column of the intersection counting from the upper left corner of the
t: q0 f# g4 d* k* h ;; world. -1 for non-intersection patches. s, C3 {- e/ m* J9 X
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; \9 {* `5 F$ F- U* O6 |& X7 y auto? ;; whether or not this intersection will switch automatically.
C% k" N( I9 I" k4 E ;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;7 p* U7 w+ S, }
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.
$ b4 _+ D0 V4 e4 [5 i+ D;; Create num-cars of turtles if there are enough road patches for one turtle to
# I) J; B, E. U* j* H' @. ]* c;; be created per road patch. Set up the plots.
5 x$ D9 k9 F7 w4 z+ x1 F1 w( Sto setup4 p) P9 {8 h' h/ B
ca
) n6 n3 r5 a3 o$ a setup-globals
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;; First we ask the patches to draw themselves and set up a few variables" O, i S2 X5 P6 j5 C) o- [& M- G l- P
setup-patches
1 w( f" d: ^; S$ g make-current one-of intersections
) C' e$ i- A; \* j- N Y label-current
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1 q& x5 R: s4 Y 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 "( V3 _9 ^: ~. c! r" W
"road. Either increase the amount of roads ". e6 k% p# L8 x
"by increasing the GRID-SIZE-X or "
: k+ C e0 c- O- d T: y2 D "GRID-SIZE-Y sliders, or decrease the "8 `; @( L5 q4 f" B$ s! U
"number of cars by lowering the NUMBER slider.\n"# {- r2 A% |" S) I6 o
"The setup has stopped.")& G2 \0 t* X+ `+ {$ Y
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
: z& f" u/ w$ @# {0 i* Z( J crt num-cars
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3 R" t; h* V$ `& l setup-cars8 C1 f' T# ]3 ?, p
set-car-color# x0 E8 z- V8 Y0 ]2 s( o$ g
record-data
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$ g7 _' _3 A) m9 M. D8 k ;; give the turtles an initial speed4 ?$ ]. ~5 f _% ^! ]3 d6 ?
ask turtles [ set-car-speed ]6 C! h7 z1 ]- d5 X/ j0 `
3 W# B" Z) J% N1 E reset-ticks- n C$ m9 ~) c1 Y, I5 c( a
end6 H+ v2 Z7 z+ Z1 X8 p; i
% h w0 m" G% w;; Initialize the global variables to appropriate values) @1 I' B1 c; M1 e
to setup-globals
0 Y& B* `0 Y3 p4 v$ M' u6 A set current-light nobody ;; just for now, since there are no lights yet
+ p! S2 v8 R& v% [$ A set phase 02 _+ A: V! m0 p! O
set num-cars-stopped 0
# V0 Q+ J( ~- A2 Y4 d# m* R set grid-x-inc world-width / grid-size-x( h$ _( Y7 b3 d3 c
set grid-y-inc world-height / grid-size-y Q- a5 `5 z7 ?4 L$ X* o; D1 r
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary d" \$ d- u R
set acceleration 0.099
9 ?$ R9 p- U9 P, p3 Eend! I7 X' `( C" i; |7 k
$ T# E. E' s; A7 o b9 D. u- w;; Make the patches have appropriate colors, set up the roads and intersections agentsets,/ Y( M9 H- x1 v* u- A: j) j$ T) `+ n
;; and initialize the traffic lights to one setting
9 i2 \1 Y L! p% O1 X/ ]: xto setup-patches2 X4 E( O3 }$ O, S
;; initialize the patch-owned variables and color the patches to a base-color0 F# @/ R$ R* c+ R
ask patches5 h& m/ }; \) C
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- l7 c7 c' ?0 A; L# v( ] set intersection? false
8 [. P* k) P2 z6 c- ~$ Z set auto? false5 }9 L" V* G3 U; M; b. r/ T2 d
set green-light-up? true
4 r, g6 u8 {% Q. ^/ L+ s+ ?# x set my-row -1
9 p! J0 F: }6 X% e set my-column -1
, y* a( B T6 s. H set my-phase -1
1 F& p- Z ?8 h+ c set pcolor brown + 3- k9 n' G( I2 T8 ~) u) J% [: I- C
]
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;; initialize the global variables that hold patch agentsets
/ ?, q: H. ~" J/ _% j set roads patches with
3 Y5 p- L; X, K$ i& D! Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 y; r7 m# T6 G1 j
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]& G1 |+ j3 v6 z; n v ^
set intersections roads with
8 ?1 z% z1 R+ c; S( M" x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
8 t. X* C2 A- [ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end
5 W3 P/ S; _8 L9 F7 M其中定义道路的句子,如下所示,是什么意思啊?
% o" v, V! {6 T3 D& {; J! t set roads patches with
) |2 L: }! Z7 a, x# @8 {! Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' k1 V& t) m) ?1 }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% ]9 ?' \6 T1 e3 f4 U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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