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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 v/ f/ }7 G) _ U1 B
netlogo自带的social science--traffic grid这一例子当中,) w7 D( H3 o# z' b4 L* d9 t0 G
globals+ ^; B k* H6 D, O- Z+ i
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2 y' \8 ]9 [0 c grid-x-inc ;; the amount of patches in between two roads in the x direction
4 `0 Z' [0 g. K' H3 n grid-y-inc ;; the amount of patches in between two roads in the y direction2 c/ A, A2 J F/ F, X; P2 n
acceleration ;; the constant that controls how much a car speeds up or slows down by if3 N ]2 C! n# o' M+ W- `( Y6 |+ F
;; it is to accelerate or decelerate# c4 X( R& f8 ~) n4 y
phase ;; keeps track of the phase6 N0 k( r% H5 [2 I
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" X+ }3 D f5 u0 ?
current-light ;; the currently selected light# h, m1 }( d* F
8 a9 h* G# I, z: q( w ;; patch agentsets u" R8 J" W- H; b1 Q; |
intersections ;; agentset containing the patches that are intersections
6 t/ Y0 J7 g- ~& @' j roads ;; agentset containing the patches that are roads2 k! @. o/ `# {/ @! Q, j" \
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turtles-own E/ J3 Y0 l) `7 [6 U5 ^4 K" N
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N% n. h! r& j9 j9 u speed ;; the speed of the turtle
- W$ \ R: K( Z4 K1 k' T9 f+ Q c up-car? ;; true if the turtle moves downwards and false if it moves to the right( P/ I4 Y6 M# h2 Z
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
( w* ]9 o+ [8 } green-light-up? ;; true if the green light is above the intersection. otherwise, false.3 [# |+ G5 i# S, `; t
;; false for a non-intersection patches.! N. V, R v' |
my-row ;; the row of the intersection counting from the upper left corner of the1 v a$ G/ L H' z
;; world. -1 for non-intersection patches.2 z1 \2 Q( C- q) j$ O" f3 ~! |
my-column ;; the column of the intersection counting from the upper left corner of the
7 V7 w' y( H- `) [! N$ H+ p ;; world. -1 for non-intersection patches., ]0 _0 P9 V% { W: C
my-phase ;; the phase for the intersection. -1 for non-intersection patches.4 ^ h# `0 N2 z% A* m9 s
auto? ;; whether or not this intersection will switch automatically.
9 q7 K/ W, E4 l: q z3 E. T1 N ;; false for non-intersection patches.
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) x5 q! N( n4 j9 Z# ?! ~) F0 k* I/ R;;;;;;;;;;;;;;;;;;;;;;7 L0 {3 r+ |& s+ [) L
;; Setup Procedures ;;: t0 x% y0 J. I7 d+ y2 o. {& T' \0 P4 j
;;;;;;;;;;;;;;;;;;;;;;
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1 Z. K; v3 ~& F. D _;; Initialize the display by giving the global and patch variables initial values.* ?- ~8 v2 F1 p7 }2 i
;; Create num-cars of turtles if there are enough road patches for one turtle to& @; |; f, Z _
;; be created per road patch. Set up the plots.
6 Z% N6 `5 n# n; p# m: F1 Cto setup: ^4 N- J1 }: I7 H4 o- m/ a
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setup-globals
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@/ N# @. j5 J! r% ]7 h# z4 z ;; First we ask the patches to draw themselves and set up a few variables6 R6 e# ]& T% m, m5 x- s
setup-patches |6 d9 M' k0 A! k* O! i
make-current one-of intersections! B& R, P+ }' B
label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)$ }1 X+ q( G7 j! y* |
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/ A% B" D1 A& r7 D user-message (word "There are too many cars for the amount of "" T- k- j8 l* O* P8 v3 B8 I
"road. Either increase the amount of roads "
6 I2 i5 R& U8 z$ k "by increasing the GRID-SIZE-X or "
P# L' I& I+ R$ O, g! V t "GRID-SIZE-Y sliders, or decrease the "
; b. T: b& x. A "number of cars by lowering the NUMBER slider.\n"+ \: O0 n! }4 D3 C
"The setup has stopped.")
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
* h7 N! I. n; `! x" k crt num-cars3 ^9 z0 s3 M N. P; @
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# c7 g& I) A0 x3 ~7 e# @1 F7 C setup-cars
9 M0 S8 U9 q3 i set-car-color7 i7 E8 D2 n9 g
record-data
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;; give the turtles an initial speed4 n. _+ R) e T. R3 o# c6 }' o: {
ask turtles [ set-car-speed ]
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reset-ticks8 o5 f8 {+ G- P3 m" G, w
end. f2 l3 z6 Y8 f D9 B
2 B0 ^- Z' G6 v( S$ y9 t;; Initialize the global variables to appropriate values) n4 P- T& Z1 V, \
to setup-globals. X! l9 X# W( s3 L
set current-light nobody ;; just for now, since there are no lights yet
W. C g0 h7 j, e6 E8 C# P set phase 0( U: a& Q' t- g0 |
set num-cars-stopped 0' L8 r! c! {% B& a
set grid-x-inc world-width / grid-size-x8 h' {& i% Q/ \) Z' I
set grid-y-inc world-height / grid-size-y6 v& @5 R) V9 u }$ E: x. v
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
U0 U) p! c8 o& ` set acceleration 0.0990 d& y5 |* n! K9 N1 g) s
end
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: H; r$ [% O3 I4 B;; Make the patches have appropriate colors, set up the roads and intersections agentsets,% L9 y. J% M0 ?' S) z- ]4 i( I
;; and initialize the traffic lights to one setting
3 G% J( f7 l5 ?2 D, S1 D9 ]5 ^2 @to setup-patches( B3 S& [/ X& s
;; initialize the patch-owned variables and color the patches to a base-color
; e# i" X0 \/ I- z, y6 O, p0 } ask patches
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set intersection? false$ v, m$ {5 W8 s& U$ ^$ n% z: ?% t
set auto? false
" V+ X$ h6 [3 s; [4 n set green-light-up? true
$ t( Z; G. l# U/ ? set my-row -14 r5 ?8 L0 P- [" m4 ]
set my-column -1
/ z" C6 Q3 Z3 w, L I/ D5 E* Q" ? set my-phase -1* L; O1 U* f& \4 f9 |2 @( Z
set pcolor brown + 3! m6 r6 w5 U% Z+ Y9 i: h
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;; initialize the global variables that hold patch agentsets
/ N$ q1 j3 {: d4 R' R8 M9 ?- b set roads patches with
5 r) `2 G0 j% d1 s3 t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 T. d. D& v, t5 a* P% w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]: Q5 n# v+ F- T& y8 R: R
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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% t. K+ |' d9 R9 p3 a' |6 M' R ask roads [ set pcolor white ]* N* I k9 x A+ X. }
setup-intersections
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. f& n/ K4 K- H7 F1 x1 \. q其中定义道路的句子,如下所示,是什么意思啊?
1 ~! k# A' T" J6 N set roads patches with2 a$ A9 x) _8 ]" i# z, ~
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( V) ^! {, h' x( ~% h- F S (floor((pycor + max-pycor) mod grid-y-inc) = 0)] E' X. h4 c. {, O, _9 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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