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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。
. P" Q1 P. q$ @+ D& D8 ^2 G anetlogo自带的social science--traffic grid这一例子当中,% q7 [/ Y+ R* B
globals
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: ^/ I5 H5 u! g2 I grid-x-inc ;; the amount of patches in between two roads in the x direction
" E, }% P6 Z, L6 m1 I0 F grid-y-inc ;; the amount of patches in between two roads in the y direction
: I& \& p& ~5 t/ h4 q acceleration ;; the constant that controls how much a car speeds up or slows down by if
" k0 J) p0 R: | C ~: N, ^( I9 ` ;; it is to accelerate or decelerate
+ v8 w- h" x1 |, K4 x8 ? phase ;; keeps track of the phase) k- `) b/ Y. V; i3 X" Y
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" m* |, x4 y# E, @ h
current-light ;; the currently selected light
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;; patch agentsets. g1 h- M6 ~3 H: |" y6 J
intersections ;; agentset containing the patches that are intersections
& h& j5 S+ q- Z: b% I roads ;; agentset containing the patches that are roads- z7 ]. g0 z" v1 a) y
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; E4 V! I9 z, f" Qturtles-own
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speed ;; the speed of the turtle
* C- T) \; q( |2 ^* Z% b up-car? ;; true if the turtle moves downwards and false if it moves to the right
, w; ~/ G; q4 S% q4 w$ q3 b) W wait-time ;; the amount of time since the last time a turtle has moved5 f! l, f8 ^7 b* U! `
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
G' n$ Z! z; p! z( {$ J/ ]/ r green-light-up? ;; true if the green light is above the intersection. otherwise, false.. r6 ]( b9 @- d3 U" [( R! F
;; false for a non-intersection patches.9 j. s5 b3 D; Q: J' V" X. c
my-row ;; the row of the intersection counting from the upper left corner of the6 G5 K) j Z2 T- ?2 B
;; world. -1 for non-intersection patches.* A' }8 h# b& w! j" s4 Z3 }5 _& R
my-column ;; the column of the intersection counting from the upper left corner of the4 [6 M4 X: s; _7 R" ^
;; world. -1 for non-intersection patches.6 C0 x) P. a$ ?9 |6 B
my-phase ;; the phase for the intersection. -1 for non-intersection patches.; E9 [' N. D2 l/ a
auto? ;; whether or not this intersection will switch automatically.
1 S( h$ P# C" ~" h ;; false for non-intersection patches.
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" Y! p9 @4 j' A% }; b, j; D;;;;;;;;;;;;;;;;;;;;;;3 F0 C4 G( A/ y7 R9 [
;; Setup Procedures ;;. @2 u% z8 Z" T' g( `2 M
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
* a. Z+ z5 R) r2 F0 D;; Create num-cars of turtles if there are enough road patches for one turtle to
6 M3 K- J% Z+ H7 L# P;; be created per road patch. Set up the plots.
" Z/ |9 i" l# s$ t# b: t, x3 vto setup4 \ k* H+ X: u6 `4 @+ `- ]
ca
& f2 f, Q1 |* b0 Z8 d L& ]. k6 g setup-globals
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4 g: C9 I) n5 G. J# j/ Y. b5 d% r7 U, Z ;; First we ask the patches to draw themselves and set up a few variables
" J$ o8 S+ I- x) {0 m2 W0 N setup-patches0 Y6 k9 _% d6 R8 L; W7 q; K
make-current one-of intersections& d+ \: U, D/ B- m/ @! a- D, f Q
label-current
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set-default-shape turtles "car"+ L. H9 u7 o+ Z' E$ A& Z
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if (num-cars > count roads)# d3 N, S$ v. Q( P
[
/ D8 d9 k3 d3 q* C) W8 v# ~ user-message (word "There are too many cars for the amount of "5 H6 a% a9 \: a& Q$ @
"road. Either increase the amount of roads "
$ I. D/ ^7 T6 C0 v "by increasing the GRID-SIZE-X or "
$ D, [. l, z3 a! |3 S- V "GRID-SIZE-Y sliders, or decrease the "
3 |! s# I/ }2 g: t7 l3 b- ^ "number of cars by lowering the NUMBER slider.\n"
" i! ]8 ~: J+ y! `$ a" w "The setup has stopped.")
# v% b* e {5 b6 H# t& R ]8 a stop, M3 O0 C# z- W, ?( u* i
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7 e* q: ~1 n5 I! ?( `5 H. K ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
) Y9 u% `: T5 L0 d crt num-cars: o2 v! c% o' K4 |
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setup-cars
+ ^& T/ E R: `9 ^( o set-car-color) y2 d1 d5 [ q: C" R E
record-data
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% E, L( n9 m3 f ;; give the turtles an initial speed
0 _, A+ m3 z! T6 R8 {6 k ask turtles [ set-car-speed ]3 L- H" K& v |
$ c- {/ Z& h$ \5 A' C% r reset-ticks- a- ]" G- R x1 e4 Y
end% B) `1 m4 _5 o& K. f% Y4 v, F5 e
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;; Initialize the global variables to appropriate values( `9 L2 P& ?9 q9 e$ L
to setup-globals+ z$ |. M' U. y( r3 K
set current-light nobody ;; just for now, since there are no lights yet( t- @9 x7 _! ~
set phase 0! Q1 x: s- C* Z, G) p
set num-cars-stopped 0
. Y$ ?) R3 N; H: o& {+ k set grid-x-inc world-width / grid-size-x
- u8 ]+ J" M1 y8 o set grid-y-inc world-height / grid-size-y
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2 `8 z# X e" S7 R ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary8 o+ ~+ \# |7 P* ?1 W" S( z# W
set acceleration 0.0994 a1 D5 j- P# D2 z
end8 L3 ] K4 Y [6 r9 M
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
/ L! j0 F/ K: U;; and initialize the traffic lights to one setting
$ t% J* g9 x9 H# hto setup-patches: O$ d, P( L' g( O$ L, X/ |
;; initialize the patch-owned variables and color the patches to a base-color$ k _ m% g$ T' F- Q
ask patches
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set intersection? false
8 X9 _; b# h, n- A; l, S set auto? false
& c6 m0 \; P; O2 I4 S+ U) g7 c2 f set green-light-up? true9 y( \: g/ t& m# C
set my-row -11 Z& f' z4 y# N! C" G
set my-column -1
2 l2 W/ w8 C: k2 i set my-phase -1, R/ ?6 w$ f8 v) G% R
set pcolor brown + 3! P/ S" x# }. [
]
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;; initialize the global variables that hold patch agentsets
; t% H0 c) d7 o) _ set roads patches with
% G9 [3 C4 i) G" S! r7 E* C, o* B [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 e3 Z6 _ z" w (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& S1 `9 @7 Y. }6 a q; @* ` set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]$ o9 q5 [% u# G2 R! a
setup-intersections8 ?2 \* Y/ t6 T7 `/ S; h
end; a1 X. w! m/ J$ I* U% X
其中定义道路的句子,如下所示,是什么意思啊?; W/ I9 r7 i/ C2 Q9 l/ M! ~, ?7 K
set roads patches with
; ?0 M" x/ s. Z P [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or: [+ }! j% S3 ]8 r
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& F' b9 I; C3 g' s/ v, 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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