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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。 C* M5 D9 r8 Q& M; }$ D
netlogo自带的social science--traffic grid这一例子当中,1 a* _, V! u/ o* G+ V5 B$ M- Q
globals
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% O* i' V4 \6 h+ o: G- n grid-x-inc ;; the amount of patches in between two roads in the x direction% b2 d. J- ]* o+ F' K. ?
grid-y-inc ;; the amount of patches in between two roads in the y direction
* o* _% W- h7 H# Q/ g/ x, j acceleration ;; the constant that controls how much a car speeds up or slows down by if+ o5 X; r' ~' Z* D, l
;; it is to accelerate or decelerate' r* x9 c% y+ Q4 G( u& N( `
phase ;; keeps track of the phase! {- r% g* }: {$ ]: g6 J
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
' `6 x3 Q7 j: g/ Q- [9 a9 Y current-light ;; the currently selected light, F; j& W ?$ u% F$ y& z5 {. W8 x5 a
8 s8 E- B" K; Z& h$ F ;; patch agentsets' x y' I& H# i, B- b
intersections ;; agentset containing the patches that are intersections C: F% m0 Y) A4 r8 c" g
roads ;; agentset containing the patches that are roads
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5 F8 A! Y7 I3 V+ [' w6 \6 n% u5 ~9 f wturtles-own# X: U# ?! f& H7 d& l% ]2 B
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speed ;; the speed of the turtle
; X6 U# \+ H% g up-car? ;; true if the turtle moves downwards and false if it moves to the right
% I8 n/ R- Y/ X: w% e7 K wait-time ;; the amount of time since the last time a turtle has moved. e) Z" b. o& J
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patches-own
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/ x! d* v$ W. O- x intersection? ;; true if the patch is at the intersection of two roads
# |/ ~ L3 q: J green-light-up? ;; true if the green light is above the intersection. otherwise, false.
2 i% T+ F) q0 }" p ;; false for a non-intersection patches.( d( U3 D8 m% M! u
my-row ;; the row of the intersection counting from the upper left corner of the J+ g9 E8 C/ d! f
;; world. -1 for non-intersection patches.% h1 i" t1 o% q+ R$ m: o* e5 x/ V
my-column ;; the column of the intersection counting from the upper left corner of the
O8 p: c6 n6 H" M0 z* g ;; world. -1 for non-intersection patches.; s+ g$ L4 U) i0 b4 ~7 }& t0 w
my-phase ;; the phase for the intersection. -1 for non-intersection patches./ y& b. p% H$ _
auto? ;; whether or not this intersection will switch automatically.
$ L; k1 A. V- S- T1 ^1 y ;; false for non-intersection patches.
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; q" J" N Y+ K;;;;;;;;;;;;;;;;;;;;;;+ h w( B& J. d5 E) x R- c
;; Setup Procedures ;;
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9 `6 g, |- v3 j2 x/ v5 S O;; Initialize the display by giving the global and patch variables initial values.5 M/ B/ `5 ~: X4 b4 y
;; Create num-cars of turtles if there are enough road patches for one turtle to% F& {7 j. @" M. f; T
;; be created per road patch. Set up the plots.
$ o" S6 n, M8 d- ?. x0 yto setup6 S% c" b4 j9 }1 c; t" a* }! p: C
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setup-globals2 B0 H8 a$ i9 m3 I& C: J9 W
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;; First we ask the patches to draw themselves and set up a few variables
% ^4 I8 M8 K3 c: C( x0 ]9 V: Q$ k1 g setup-patches
: R& ~* ]( g4 J Q3 n: D- Y make-current one-of intersections3 X2 c% u8 D" T$ S
label-current- r' B) [. r: _) k" P9 H
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set-default-shape turtles "car"2 \& M/ t" f9 J2 h$ w
' U' d! \" N& p: b if (num-cars > count roads)
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" C( i$ O' Y) P( @1 Z user-message (word "There are too many cars for the amount of "! }% w: i2 i% `) o6 c& S
"road. Either increase the amount of roads ") Q( R* o9 ?4 Z% s
"by increasing the GRID-SIZE-X or "
2 D9 L% t4 f9 B3 ^ i "GRID-SIZE-Y sliders, or decrease the "4 \3 c) J3 E; D& C5 l( l" J
"number of cars by lowering the NUMBER slider.\n"
2 K4 W+ d3 q! j; N K7 e "The setup has stopped.")
2 F! V/ I3 I6 k7 P2 X! _6 y stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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1 g- `) G5 F/ h* }5 s1 D" Z8 _ setup-cars. e/ l# \4 x _. ]" z
set-car-color
; z8 e( W- ^( o) L- H0 M+ e6 q record-data1 @) |. j5 j8 P. D& V
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;; give the turtles an initial speed# q, o" x' R9 W$ [5 |. ]7 A) a6 ~# R
ask turtles [ set-car-speed ]
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, p; ^ J% m$ V reset-ticks( ]5 @: U0 z* ?$ T) |
end
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;; Initialize the global variables to appropriate values8 e* P/ u+ C$ ^8 L+ F5 z+ ^
to setup-globals& [' H& Y- M' S k) `: W, v
set current-light nobody ;; just for now, since there are no lights yet
0 n- o6 x' q' m6 N3 q8 N5 Z set phase 0' i( B( O5 Q5 y' i A
set num-cars-stopped 01 C& U. \0 f5 t. Q* z5 j
set grid-x-inc world-width / grid-size-x
0 w4 K* [5 f/ f" O: b9 j2 F set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
6 J* G0 i1 \9 E set acceleration 0.099
% u- }. p1 [2 j7 @: p$ `( B# ]end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,. q, I `. @0 D4 X% x
;; and initialize the traffic lights to one setting
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;; initialize the patch-owned variables and color the patches to a base-color
. f4 K& ~/ P v7 G, d4 L( i ask patches
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set intersection? false
0 q( X' J* _. _ set auto? false/ Z1 H- T9 ^+ I7 H2 T5 z9 X
set green-light-up? true
; I8 |- |3 {, [9 x7 X* e set my-row -16 f: V3 x+ T0 H8 B' s
set my-column -1% ]# c! @7 J& L+ b6 U
set my-phase -1 w" }+ J9 C$ S, f
set pcolor brown + 3% p1 o7 _* j. ?0 Y- K+ |. Y
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;; initialize the global variables that hold patch agentsets3 R( O: C1 R& N9 N
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, m% h; R8 N- X1 H9 a set intersections roads with& v5 w: g! x9 R" M! X% G& [
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ N4 ~1 u# x6 j& ^4 y (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end
7 d g# H7 j, P: W4 \5 A其中定义道路的句子,如下所示,是什么意思啊?
& H1 G# d8 p, ` set roads patches with+ _ x5 Y+ e7 ^2 D( b5 J
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or1 O- x9 m; B- ^% r! ?8 h) @
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# S7 ~' o1 R" R9 \- x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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