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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。
5 K+ H3 Y+ I( u9 Z$ Y( Dnetlogo自带的social science--traffic grid这一例子当中,
0 H# U% I W) u0 W2 ~, p0 Dglobals4 p* B+ n" R) M2 f4 H
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grid-x-inc ;; the amount of patches in between two roads in the x direction
$ i! D+ X( r) Q' v2 ^7 d* ^5 M1 Q grid-y-inc ;; the amount of patches in between two roads in the y direction
2 x! J P( s% k8 c acceleration ;; the constant that controls how much a car speeds up or slows down by if9 k; @. C- X8 H" v0 H4 r
;; it is to accelerate or decelerate
9 V: k2 P/ b, k, S phase ;; keeps track of the phase
9 ?8 g4 k$ B1 v L0 ] num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure- S) Z/ g2 g. h, l4 g5 X
current-light ;; the currently selected light' i$ }/ a u. ?) X% i
0 c& b: h: G# c' _6 h ;; patch agentsets
5 W& V! j4 Y* b* M) I, b2 e intersections ;; agentset containing the patches that are intersections
/ c5 Z% x$ y5 L roads ;; agentset containing the patches that are roads
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turtles-own
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speed ;; the speed of the turtle
. v, |* B* V7 p# T* C h: F& Q/ l up-car? ;; true if the turtle moves downwards and false if it moves to the right5 X7 k/ S4 |% w& s6 f) D# _* b+ C
wait-time ;; the amount of time since the last time a turtle has moved/ ^. S) P, Y& H* g
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8 `( _0 S" t6 S& o) {* d$ {5 W8 ?patches-own2 i9 v+ x r0 f, J3 Y4 u3 b
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intersection? ;; true if the patch is at the intersection of two roads8 m, G( i4 g5 t1 G$ {! {0 S
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
U3 r& P- e. ]4 Z+ p ;; false for a non-intersection patches.8 C- o! }8 [% N- ]
my-row ;; the row of the intersection counting from the upper left corner of the
* b7 k' Q0 } N& r0 `3 O" T9 C& ] ;; world. -1 for non-intersection patches.
' a2 u* A N2 C my-column ;; the column of the intersection counting from the upper left corner of the
1 h y: i0 X% N$ Y ;; world. -1 for non-intersection patches.+ g; a% Z/ c+ J3 F1 M- u
my-phase ;; the phase for the intersection. -1 for non-intersection patches.) G! ]2 \' G( m4 K; J( x7 F
auto? ;; whether or not this intersection will switch automatically.
: i8 n6 z3 i" f6 _1 G0 m! a' x ;; false for non-intersection patches.
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6 n3 ~# X) T1 E7 t& V" ?;;;;;;;;;;;;;;;;;;;;;;
; }4 J! N4 y9 Y0 E3 G5 d8 O# z8 ^;; Setup Procedures ;;
, {4 M9 w) S$ A3 R; g9 l;;;;;;;;;;;;;;;;;;;;;;
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$ g. e2 b: c# l7 p$ x; N;; Initialize the display by giving the global and patch variables initial values.' b& ~! L; ?: s
;; Create num-cars of turtles if there are enough road patches for one turtle to
1 |4 ~1 c* L: ]( y9 l$ [/ w" j;; be created per road patch. Set up the plots.1 D6 e' f+ a, v
to setup
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setup-globals* S A. r h7 K, y3 @ z
( L" p" Z; \- `) m* {0 X ;; First we ask the patches to draw themselves and set up a few variables
) n! w3 f; v, x* P setup-patches, |* @, ]6 \9 ^$ m* s7 ]; r
make-current one-of intersections
' f+ V0 u8 N f- b: r# T; h label-current
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% J6 ^4 ?; {1 b) V9 j+ L set-default-shape turtles "car"
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3 l1 n& w/ u$ Y: B9 [6 U. x if (num-cars > count roads)
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% E1 _ D9 O7 _! F user-message (word "There are too many cars for the amount of "
& J- ^( |5 ^6 F4 u "road. Either increase the amount of roads "
& K6 q3 A7 Z/ ?1 d+ `& u) a2 K "by increasing the GRID-SIZE-X or "
2 g# {' H. o- z" y5 L "GRID-SIZE-Y sliders, or decrease the "8 ^- e* l4 D2 Z6 T- L
"number of cars by lowering the NUMBER slider.\n"
5 h' J, [/ R% V "The setup has stopped.") k4 m; j& x; O: ^( O2 e( r
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color8 l8 N5 M% |8 U3 Q5 W' V
crt num-cars
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) o* c g* j& A# V setup-cars+ U/ M* B, j" m) T+ @) F
set-car-color2 K: b: Y" ?4 q& e" ~
record-data+ f8 F# a) t% s$ f; g& ~
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1 ]2 O4 ~0 E0 V6 y7 i" q ;; give the turtles an initial speed$ w# r0 H$ J" u5 B) a
ask turtles [ set-car-speed ]$ P1 E% A& I* ~, D- a0 k
& @1 q8 b1 h5 M9 v9 e reset-ticks/ u# @6 S3 L. T
end
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;; Initialize the global variables to appropriate values
& d; s' d: `- j8 s8 O/ I: Hto setup-globals1 O% }4 D: j* o0 o8 q" |
set current-light nobody ;; just for now, since there are no lights yet
- v- R5 J' ~+ ?# j set phase 0. W/ Y6 w' w8 I1 X% M7 A
set num-cars-stopped 0
3 B' g" k3 t3 G d; x; k8 g, x set grid-x-inc world-width / grid-size-x1 G' r& B T% h5 K" f. O& y3 y- h* }
set grid-y-inc world-height / grid-size-y
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3 k1 X+ t- a& O2 `" b ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary0 U0 u6 {/ f: P
set acceleration 0.099* Z; i N6 ]3 E& U
end
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0 H' P8 k1 S9 }7 T$ L* c& g7 D;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
1 i; w' J! w$ b3 d3 |6 _;; and initialize the traffic lights to one setting% ^9 t5 u V- p# d. s
to setup-patches7 {1 P+ t- t3 E; _/ N$ R
;; initialize the patch-owned variables and color the patches to a base-color- c! z; G, J" ~" X7 d1 H: T* G) D
ask patches/ J! v3 Z+ ~" r' E" x
[
& p6 D' }: L8 X% L# a3 y set intersection? false1 } U* O8 A6 y7 r; Q/ |
set auto? false
( M1 O* \$ W( Q) U$ J0 G' D9 L set green-light-up? true
: l; [6 B) X; _8 | set my-row -1 p. x0 ^- i: b7 y1 p) E
set my-column -1) t2 }1 ^6 h9 J
set my-phase -15 C) I" W R; y
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets2 \- M; T: Q" [# `/ r2 f9 X
set roads patches with/ D) D' _! Z! y% d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, o$ ]% ~! u6 _2 q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ }. M! B1 {# v' J9 Y( u5 Q set intersections roads with
0 l0 p% i9 `) {& U [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and$ a; X8 D3 p, a2 v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 Q/ r% B+ h" Y" t8 l. {
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ask roads [ set pcolor white ]- u* ~1 J! k, A4 k, {0 D4 A
setup-intersections
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2 k" v( C% W; v2 g" ~) a其中定义道路的句子,如下所示,是什么意思啊?
5 ?+ }3 O9 H" }* E. B/ y6 @ set roads patches with
4 }6 u3 D4 k% c [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& x4 T; Y7 z9 s$ _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 w G$ V$ J0 G R$ k" M& 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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