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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。4 u& ^$ P n! o* J6 A9 {( ~ {
netlogo自带的social science--traffic grid这一例子当中,$ b# ^; i6 h0 C2 q1 i
globals
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+ @( s/ C3 Y- u4 { grid-x-inc ;; the amount of patches in between two roads in the x direction
) {0 l \, m- v0 k6 i grid-y-inc ;; the amount of patches in between two roads in the y direction
/ e( R. i4 N. g acceleration ;; the constant that controls how much a car speeds up or slows down by if* I5 A" k; N5 F. ?& S+ p
;; it is to accelerate or decelerate* n, v t* U5 }6 K! {9 ?, D4 l/ I8 H
phase ;; keeps track of the phase8 t. y2 m- C+ _
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
% F q$ e) j6 ^5 C6 M' _; X! z current-light ;; the currently selected light0 r) g y0 j. C( U% d1 @6 V7 `
" _: ]/ q: \$ }5 f) a5 H5 E' l ;; patch agentsets
' g W. f' S5 [2 \! \ intersections ;; agentset containing the patches that are intersections: |# ^5 i' Q# v4 A i; c3 R
roads ;; agentset containing the patches that are roads2 P- A, J* T/ y
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, ?" @$ p% D& q2 Aturtles-own
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/ {, A) w) i: |+ ]) e. [/ Y speed ;; the speed of the turtle# ]( M2 M d6 x. Y7 V9 r& l
up-car? ;; true if the turtle moves downwards and false if it moves to the right/ e+ l+ `# a% ]/ b3 R, z$ b
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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) B$ O2 p! |/ M( r- a) ^( ]- P intersection? ;; true if the patch is at the intersection of two roads
2 H. A2 y& d9 F: t; G green-light-up? ;; true if the green light is above the intersection. otherwise, false.5 B: r: r% I( [, \* G3 P% J5 ^
;; false for a non-intersection patches.! Q ~" ]' q1 b- W: h
my-row ;; the row of the intersection counting from the upper left corner of the- d, g: }. S5 v6 e
;; world. -1 for non-intersection patches.
2 N6 y/ I# I% U; E$ \+ W" ] my-column ;; the column of the intersection counting from the upper left corner of the) J$ i$ j, ~' L$ Y. E, l" t
;; world. -1 for non-intersection patches.
1 {# s+ X6 H% |) X8 r8 P! N my-phase ;; the phase for the intersection. -1 for non-intersection patches.% M, Q- ~; m* z
auto? ;; whether or not this intersection will switch automatically.
/ b0 R: W- l; P2 P% ~ ;; false for non-intersection patches.
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, D& u+ A: W# S: E4 a; Z;;;;;;;;;;;;;;;;;;;;;;
; C% L7 K# X9 f0 c;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.; e& F" J# E' r# _
;; Create num-cars of turtles if there are enough road patches for one turtle to, v0 Y. r T/ M+ E
;; be created per road patch. Set up the plots.' y6 j" N3 ?/ @- k* @2 Z! ]
to setup( n8 f3 w: ^! ~% |% s
ca
9 U! m4 ?* `3 U6 o setup-globals
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5 U7 q' J2 K, y+ q' v( s/ l ;; First we ask the patches to draw themselves and set up a few variables
7 |7 }2 s. l. l9 E8 K& _ setup-patches
5 O) L2 g5 v. [. m" `4 z make-current one-of intersections3 M9 ]6 O" C) @2 M
label-current$ p7 T3 p( I5 s
8 j) w9 K& X& G+ _2 t set-default-shape turtles "car"
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if (num-cars > count roads)) q* C% w* Q& f* A) D
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user-message (word "There are too many cars for the amount of "7 I: D# O% J6 `4 v$ }! ]6 X O
"road. Either increase the amount of roads "" c5 B" |+ I" D4 o) b- H# @
"by increasing the GRID-SIZE-X or "2 }& T+ i9 t* }4 d& m9 w
"GRID-SIZE-Y sliders, or decrease the "9 k* x$ s8 r. ~, n
"number of cars by lowering the NUMBER slider.\n"; F& A5 W8 i: r' ~5 b) I8 g
"The setup has stopped."); H! e) \# w# O6 g' H' l
stop' D. I l% P' K, V+ t. k
]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color6 C+ ^3 ?* c7 V2 W; Z0 m7 C+ y
crt num-cars9 x- p- U1 k2 D) L8 k
[
1 B+ o( k5 B' p2 d setup-cars
% E- d4 p g3 }( p5 ^0 Q set-car-color% B5 p4 w; _' I7 I4 p3 j3 K9 H
record-data4 Y+ F* a( b0 c9 \. p1 i' f
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;; give the turtles an initial speed1 ]# Z5 V0 r9 z2 V( s
ask turtles [ set-car-speed ]
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: h3 q- F9 {; F: U" ~ reset-ticks
' V. Z4 z) l2 kend
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;; Initialize the global variables to appropriate values
; `0 u0 F7 ?& Z5 n3 y* T1 b; Z( |to setup-globals
4 g$ [8 N/ |! l7 [ set current-light nobody ;; just for now, since there are no lights yet9 ? x; N; K/ v! F
set phase 0
1 G7 B3 ^# @' R5 E0 r set num-cars-stopped 0
; }, P0 o. \; }- f f set grid-x-inc world-width / grid-size-x
' j# T2 i4 z! A: |( {2 @$ `2 r set grid-y-inc world-height / grid-size-y
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) ^) h, }0 r2 _ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
" L! C# V0 h4 g, [, m: x. J! X set acceleration 0.0995 \, I J4 ^( Y Y
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
- q8 J9 Q, h9 n: }+ Y;; and initialize the traffic lights to one setting6 V9 @2 o% ^# t9 L- B
to setup-patches( [: F% U4 F% @" q, f; y
;; initialize the patch-owned variables and color the patches to a base-color7 ^. |. T5 P$ Y4 }6 p6 O
ask patches
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9 m! j4 |0 F6 L, e set intersection? false
1 s/ N: n [: o/ ~9 O x) X" l set auto? false* A+ g' N: I$ v5 R
set green-light-up? true
; c- W2 D& v; D. Y set my-row -1! {5 C2 h/ b' A7 R" K1 E
set my-column -14 `9 N7 t' l; D; w
set my-phase -11 \# l/ j# d3 x1 d9 q7 U
set pcolor brown + 3
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/ V& o- H L* ?; n! I ;; initialize the global variables that hold patch agentsets5 c/ m' B" B0 ?# V8 O% K7 b+ g
set roads patches with
" }* @5 t) h9 j6 M [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or" o) S# r/ l" ]9 A6 }+ A& l9 [5 |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
9 }9 w6 u; b* f/ R2 |! L5 w set intersections roads with
9 E* ?& [- M0 m [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and K { ^4 y3 q, B1 Z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 ]1 q3 T4 }5 } m' [( P+ S! E
: ?6 {8 J8 C1 e2 n ask roads [ set pcolor white ]
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end
$ n: A$ {9 C% M- L% K$ {0 C# E其中定义道路的句子,如下所示,是什么意思啊?
4 \6 k& }; I1 x8 z }" K: N" i8 T set roads patches with4 Q8 H0 r g7 [, ~- }4 B
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or8 }" Z5 ~8 y' Z9 [. Q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- o5 C2 C) c; f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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