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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。
, q/ I+ _1 y& |' Lnetlogo自带的social science--traffic grid这一例子当中,4 t2 U$ z' `+ _, T5 y. X; K
globals3 U' [# u% [# R6 ~5 U+ C' q
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grid-x-inc ;; the amount of patches in between two roads in the x direction
) h- Y/ b+ J& j) ~ grid-y-inc ;; the amount of patches in between two roads in the y direction7 _' T8 z5 U4 G, @: t7 g
acceleration ;; the constant that controls how much a car speeds up or slows down by if
0 h8 u t [, U; S' ` ;; it is to accelerate or decelerate
% N _: Q# G" B+ s phase ;; keeps track of the phase- K# U" w- @1 D) }) E) \7 |
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
+ `7 s1 b0 H' ?1 S: T current-light ;; the currently selected light
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;; patch agentsets) q9 w/ B; _9 m' r
intersections ;; agentset containing the patches that are intersections' o, O8 q! w4 s6 @+ k: [; {
roads ;; agentset containing the patches that are roads, O2 s% k- [& c+ Y
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; G( O9 m$ u( g: T' W6 y5 _turtles-own" Z) j* _0 o; T# Y* p
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4 N& P! f$ C/ W- V, Q8 g; D speed ;; the speed of the turtle
2 _: w6 l2 |' `' k7 S: W up-car? ;; true if the turtle moves downwards and false if it moves to the right
9 l) I9 e2 m8 | wait-time ;; the amount of time since the last time a turtle has moved8 I& ~! ?6 A- x* P( x6 w9 C
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
+ Z/ F. W( |- j, R green-light-up? ;; true if the green light is above the intersection. otherwise, false.
9 E! @& g$ m, t7 p3 G4 a- e7 M4 } ;; false for a non-intersection patches.
8 C6 r7 ]2 G+ f7 P) w4 c) {% G my-row ;; the row of the intersection counting from the upper left corner of the
! ]! A& B7 C2 G6 U ;; world. -1 for non-intersection patches.) X/ g) q6 J2 _1 c
my-column ;; the column of the intersection counting from the upper left corner of the% L5 O: w( r7 r% P$ v
;; world. -1 for non-intersection patches.
& U: p( O( c9 z6 J1 A5 _ my-phase ;; the phase for the intersection. -1 for non-intersection patches.. y4 ]. {: ~/ o$ [" [$ d. _9 n& o. X
auto? ;; whether or not this intersection will switch automatically.$ ]% H& S: ]. E; z0 @
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;
0 @3 A, l* {/ {* {8 w;; Setup Procedures ;;/ W6 A+ i: C& q2 u/ [. _
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;; Initialize the display by giving the global and patch variables initial values.
2 v$ o" a. k$ _8 ?* z0 u;; Create num-cars of turtles if there are enough road patches for one turtle to
% t* _1 J) J' f: L6 G. A: u9 ];; be created per road patch. Set up the plots. @' I) B' c$ a3 k
to setup3 m! I# B6 m( W- ]. q
ca
2 c1 j5 W t0 i; l& c4 X setup-globals) j8 U5 O, {6 V& q
: u- u2 i, P& F3 I* i8 j0 ^$ E ;; First we ask the patches to draw themselves and set up a few variables4 S" Z4 m) J* F4 ^
setup-patches2 I6 | C$ F F
make-current one-of intersections
9 j2 Y# C+ ]* p9 g label-current
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0 q8 t' y% @! A: A1 r3 j6 l/ d set-default-shape turtles "car"$ A6 j' e4 a# ` F
! r' I& K: y7 |' ] F2 | if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "/ O" `0 H, U. C0 t/ @& n7 t0 \
"road. Either increase the amount of roads ". i$ `0 b9 [% c# h
"by increasing the GRID-SIZE-X or "
) ^; j$ s. k* `, A, `6 w/ k "GRID-SIZE-Y sliders, or decrease the "
# Z4 [9 P! \ S "number of cars by lowering the NUMBER slider.\n"
2 m* |6 \+ Z, ]* F "The setup has stopped.")
J: l5 f1 N2 N W. R: S @ stop4 Z) a4 N! S; ]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
) G+ { Q2 `4 k S, Y$ M crt num-cars
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setup-cars* `5 {$ K4 \" {$ e* j
set-car-color% w9 D, P4 k& ]! {
record-data+ O6 I! K% ^, J# P6 O6 X3 Z3 k
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/ H8 z+ C( `1 H6 \ N ;; give the turtles an initial speed/ B% o2 h" x' V
ask turtles [ set-car-speed ]
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* {; W8 R$ `9 A( t: A8 x# Q/ P reset-ticks0 M( m" N4 X0 e2 z. C2 }" E! C
end8 S" i' {& @7 y2 M$ a
9 y+ d% q8 T# Y;; Initialize the global variables to appropriate values
6 I8 u( K" C. T# a( Lto setup-globals0 A6 \+ R- P1 B, z3 a
set current-light nobody ;; just for now, since there are no lights yet
7 f7 x; o9 g+ V- \( Z set phase 0
, T `. m7 G' H* S9 v set num-cars-stopped 0; ?, C6 G7 v. ]9 c$ H8 ^
set grid-x-inc world-width / grid-size-x: v2 J8 F% q o% d* r( ?' M% e
set grid-y-inc world-height / grid-size-y% j' T0 S/ v2 K/ u# r9 {8 r* z
1 U* \' H1 S$ E" O, m5 F ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary# y4 `' D* |- O8 ^- {
set acceleration 0.099) T3 e# Y. v/ Q) Y
end8 o0 ^# B. A; S
5 U# D6 |% e* c+ P$ [;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
3 M9 M+ V9 O; v6 P( u& o;; and initialize the traffic lights to one setting
3 G0 u( x( ]* b1 zto setup-patches8 ~4 o' l" J0 q ?3 R
;; initialize the patch-owned variables and color the patches to a base-color* ^2 A1 `3 [: D
ask patches; m9 G: W% B/ s! f. s' A' p' }3 ~. ~: ^
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5 r( K- V# J3 [6 @3 o5 H set intersection? false
& [, _- Q9 {$ X) d# e set auto? false
! m E @- U- M: W$ ^ set green-light-up? true4 R, ~+ G- n1 D
set my-row -1
: T" W' R" {4 t0 F, V. l) [ set my-column -1: P: g$ f7 b1 b" |! Z
set my-phase -1
0 _$ `; x- p. w: o set pcolor brown + 3: }( w+ ?7 i8 D; w7 |: m/ x: u
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;; initialize the global variables that hold patch agentsets( ^' C9 c( f. [1 e( y
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 F% w1 N7 m+ x$ A$ Q( N; ?" q set intersections roads with
; u) b& w4 {% [! f, K1 I. a( D [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
/ I7 p0 i& I$ D7 n4 j. p; h) \- z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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0 |0 z# ~1 D x: D/ K4 f9 B( ~ ask roads [ set pcolor white ]& L2 P0 s- q4 L9 y3 |4 T
setup-intersections
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2 S$ e1 G+ v( K' c/ ?其中定义道路的句子,如下所示,是什么意思啊?+ C/ P% |! f5 O% e1 W; |4 I
set roads patches with
& x+ K% A3 B6 y4 `/ f1 [( { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 c% u6 p4 Y8 c (floor((pycor + max-pycor) mod grid-y-inc) = 0)], x; Q, D# }0 t( l d% B
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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