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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。
2 _+ E i% D( B7 pnetlogo自带的social science--traffic grid这一例子当中,
) K- A! \8 w6 r$ tglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
: h/ l+ P' {2 V' f7 f& w grid-y-inc ;; the amount of patches in between two roads in the y direction
9 U" k: W" t* a acceleration ;; the constant that controls how much a car speeds up or slows down by if
+ d( n$ [, |6 C1 _ ;; it is to accelerate or decelerate
6 `) a \, v. n% v9 v/ C0 D phase ;; keeps track of the phase! B B% i3 B( }8 l5 R2 z
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure ~/ m+ l8 z2 \3 P+ {0 Z1 A
current-light ;; the currently selected light
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;; patch agentsets/ z. s! j- C! ^. J0 D
intersections ;; agentset containing the patches that are intersections
7 S+ @2 Y6 h+ s) s9 ^( L roads ;; agentset containing the patches that are roads
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turtles-own" \2 x8 x0 t0 ~, m! O
[
* E4 b5 H0 U5 W! @% v$ u speed ;; the speed of the turtle
1 Z# O6 X& O: ]( o0 q up-car? ;; true if the turtle moves downwards and false if it moves to the right/ E- @8 H9 G! E6 g) a6 D5 N
wait-time ;; the amount of time since the last time a turtle has moved2 E+ D* m$ \$ A* n$ n! @) Z
]" `1 N3 C4 q4 Q9 Y
7 n4 Y5 ]+ v' E) s% Fpatches-own
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: `' {" P2 F- F! G/ q intersection? ;; true if the patch is at the intersection of two roads
2 k/ p1 [4 E# e( V$ ~: H8 Y green-light-up? ;; true if the green light is above the intersection. otherwise, false.) c$ O* N; M9 \0 b5 U. a0 A2 t
;; false for a non-intersection patches.
@9 u7 i7 v- Z) @3 r* S/ T my-row ;; the row of the intersection counting from the upper left corner of the
- c" A: p0 b2 c6 y' U ;; world. -1 for non-intersection patches.; \& u0 }" L- U3 F- L& ]5 \4 B
my-column ;; the column of the intersection counting from the upper left corner of the; I# v% l) s+ v; G: q M1 j7 o
;; world. -1 for non-intersection patches.
+ a3 W0 i; X( @0 C: o; X my-phase ;; the phase for the intersection. -1 for non-intersection patches.% V* K& G5 I; \3 p/ x
auto? ;; whether or not this intersection will switch automatically.
8 k) ]* m; Q2 c ;; false for non-intersection patches.
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$ f+ V" x' Y& m; \+ Y! b( N9 \: U3 E0 Z" Z6 O# l* q6 ]
;;;;;;;;;;;;;;;;;;;;;;
4 @) [3 h+ G/ B5 m& l0 S: M) }& T" |;; Setup Procedures ;;
6 a7 L8 S# _! Q! B8 ^0 ~" f;;;;;;;;;;;;;;;;;;;;;;% Z& n; k, s) ^
+ `, e8 A4 t# g;; Initialize the display by giving the global and patch variables initial values.+ d" |0 o# F9 ^' r3 z" j
;; Create num-cars of turtles if there are enough road patches for one turtle to& f0 x8 U/ E$ O3 y* {% v/ @1 ^. j7 ]* L
;; be created per road patch. Set up the plots.# \6 U4 L; M+ Y; ~& K7 @
to setup
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setup-globals2 I: Y! p' r1 W, Z; b1 W
8 R+ D3 N5 _' j2 a- G ;; First we ask the patches to draw themselves and set up a few variables7 E/ @$ V6 v2 ]) I0 y* r
setup-patches
2 L# g6 \* e+ r& d% K make-current one-of intersections
* w+ A6 U' m7 ~2 A; ^ label-current5 `$ X8 }" _" T2 O, d5 b" V K( E; Q
) g% ]# [9 W, F* `; Q8 S: Z$ Q set-default-shape turtles "car"" n7 K- I$ ~. `
2 K5 Y9 m/ H( s, G( M% J% M if (num-cars > count roads)& t- k0 O I9 y$ k0 g3 Z/ M1 S
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user-message (word "There are too many cars for the amount of "
. u W8 U; }! I "road. Either increase the amount of roads "7 Q! Z2 ?& g$ B* F
"by increasing the GRID-SIZE-X or "" {, X7 u+ C2 V5 v
"GRID-SIZE-Y sliders, or decrease the " {2 `+ ^4 {% S6 f* @5 i( r2 N8 Y: x
"number of cars by lowering the NUMBER slider.\n"1 q" }. d/ d; z; A# i X1 ?
"The setup has stopped."): ]/ v* v% D6 {9 G) e# }+ q
stop6 h, ]7 g- N* L
]1 \0 S v5 P; }
k4 {. G/ M/ L8 a& h4 a* J7 b( i ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color/ ^0 Q& e* L. J8 f2 B7 W
crt num-cars
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setup-cars# @2 d, {7 F9 }- r) z7 w) P
set-car-color
: @8 n$ _, s8 F2 k& X record-data
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;; give the turtles an initial speed
5 D3 ]4 P O5 Q( t, H) g2 z* g$ u4 P: F ask turtles [ set-car-speed ]
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reset-ticks5 g* o) t. I+ h5 W3 q
end9 x8 b' e6 q7 q" z, H9 B( Y- N& A5 I2 o
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;; Initialize the global variables to appropriate values1 V& }7 Y0 S3 ^* C
to setup-globals/ K6 g3 ^, M% {
set current-light nobody ;; just for now, since there are no lights yet: p! p( o f' }/ o- s
set phase 0; M; N- i2 K2 g
set num-cars-stopped 0: Y" T9 g6 x+ _6 q* B8 q( o
set grid-x-inc world-width / grid-size-x3 I/ ^$ ]5 o5 i( n; [% J
set grid-y-inc world-height / grid-size-y5 W6 e. F' r: }$ K7 M: d2 ]
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 k* u# ~8 o F7 T
set acceleration 0.099+ n3 U1 T9 `0 n, p
end
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9 h. k, P9 c( R;; Make the patches have appropriate colors, set up the roads and intersections agentsets,$ k8 G0 a9 W! g4 @! t. O0 ~
;; and initialize the traffic lights to one setting$ q& P2 [$ q/ t0 h- q: y2 q& k
to setup-patches3 O- s4 G: v. T0 N. j. s
;; initialize the patch-owned variables and color the patches to a base-color- h! B/ C1 T" j5 _- R6 Z% n
ask patches% c4 |7 i: d% y. }* I5 G
[
9 t( X- G2 @% q9 Q# r set intersection? false, E1 N$ T( A! V/ K7 }2 z! X
set auto? false3 J) X- c7 q4 j; s. D; G1 {" ` _" U
set green-light-up? true
U1 e; e, N X9 @- C set my-row -1
/ [* ^; f( X) H. z: c set my-column -1! w# ~5 m0 l( N0 ?
set my-phase -18 f9 D" M2 j5 l' Q% K _( @! g
set pcolor brown + 3
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7 @5 P2 V' x( R$ P ;; initialize the global variables that hold patch agentsets6 |# q3 O) K" i9 [' H
set roads patches with& P/ K( f9 u6 \/ M% k
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: L' p' n- p, G
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 B6 s& U: G( j4 @ set intersections roads with( w7 Q W* H! V' k* ]0 S1 d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and& t: k3 X; U6 [2 G
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]( ?& o$ V. R0 }
1 @4 M) K5 ^( x; ~2 j8 e& i# x ask roads [ set pcolor white ]# k' }/ [1 ^) \1 g/ o
setup-intersections: }- x! @: q0 i1 d: f
end
$ }: ?3 I x1 E: M8 Z其中定义道路的句子,如下所示,是什么意思啊?
- |3 `: v& K; x) k% g% C set roads patches with
+ f! F1 H! T2 ]: z. N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& a5 @( `+ Z9 }! n7 }; X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 }5 q5 A! {/ N# X0 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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