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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。 Y4 I+ o$ c# l q8 I" P7 M' P
netlogo自带的social science--traffic grid这一例子当中,
. b+ P3 X. _6 ~1 @3 m% Q) bglobals0 S/ L N$ t8 k, I; s4 E7 d
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. S* o9 c( {8 Y grid-x-inc ;; the amount of patches in between two roads in the x direction2 E+ N# ~* _2 n
grid-y-inc ;; the amount of patches in between two roads in the y direction
2 x3 t, P; X" B5 f6 H* y; g acceleration ;; the constant that controls how much a car speeds up or slows down by if
0 U. D6 q. k6 m. X ;; it is to accelerate or decelerate4 ]" D; S; z* ~; U
phase ;; keeps track of the phase- G0 g+ `; ~" H: L* p- v% W* E
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure3 i' O) \. o* Q# F3 c# A$ r) L: W
current-light ;; the currently selected light/ a+ [3 \" v$ |
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;; patch agentsets5 u7 T: z8 u) o+ |) q0 b
intersections ;; agentset containing the patches that are intersections1 M0 \. a2 J5 O# C; z4 y* }
roads ;; agentset containing the patches that are roads" s# {, F9 k* ]
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( v( p& S5 n u5 F% X. x" ^' Vturtles-own
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speed ;; the speed of the turtle K$ p K: G* ~ A
up-car? ;; true if the turtle moves downwards and false if it moves to the right
. s+ ]/ i7 y; ]6 h1 F wait-time ;; the amount of time since the last time a turtle has moved* j3 Y* s5 V, _' G1 [% E
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# G" o7 G0 @. ?! }; `6 Z+ G+ Tpatches-own4 Z1 a$ N' s" W3 V# }
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intersection? ;; true if the patch is at the intersection of two roads2 `8 N0 F3 H6 S9 ]
green-light-up? ;; true if the green light is above the intersection. otherwise, false.( I+ G9 w6 H9 ^, ^9 E
;; false for a non-intersection patches.
, y) l( l& @; l W8 @/ _9 x my-row ;; the row of the intersection counting from the upper left corner of the; w6 e' n1 @" F! M& I2 l
;; world. -1 for non-intersection patches.
2 v, K1 M6 H- p2 m# W( R0 D7 @ my-column ;; the column of the intersection counting from the upper left corner of the/ K! n# W1 ]) L
;; world. -1 for non-intersection patches.
3 M4 a0 `0 R# t5 I4 q% P+ v% { my-phase ;; the phase for the intersection. -1 for non-intersection patches.
: J# G4 z$ |( F2 ]6 Y" o! L# V auto? ;; whether or not this intersection will switch automatically.) K l4 U) T1 i/ D1 x
;; false for non-intersection patches.& @; n1 W3 ]4 T( F; W* V
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9 F3 p; ?' d! p. e+ u;;;;;;;;;;;;;;;;;;;;;;
6 P' k0 B0 A X5 h7 _- z, S;; Setup Procedures ;;
' |" h% s1 c" V$ B" r7 W9 i* q! X' f;;;;;;;;;;;;;;;;;;;;;;! Z, N3 N* C) `. l: s3 g) u+ p
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;; Initialize the display by giving the global and patch variables initial values.
. h: S( l" m: a9 l6 b- c;; Create num-cars of turtles if there are enough road patches for one turtle to% g3 ?. e" v* l, f3 X' _
;; be created per road patch. Set up the plots." o- e5 [/ r5 {0 K0 `+ E5 J9 \
to setup
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- t, i6 X' k8 g2 n5 w setup-globals* L0 w* t: Q$ y
1 {$ [' `; k; F% k* K5 b ;; First we ask the patches to draw themselves and set up a few variables$ |5 b$ a1 K. P) X; t9 p% Z
setup-patches) c1 |% C1 E4 p, k9 v
make-current one-of intersections
9 o/ m3 l) O$ [; `9 h; j0 t label-current( x# l9 b9 X8 \1 N9 _! \, @
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set-default-shape turtles "car" ^* r) X: l0 n* i4 P: ]5 ]( S5 R5 i
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if (num-cars > count roads)
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( n) }( ]& R, Y# l% \$ A user-message (word "There are too many cars for the amount of ". h& s, @; d& i. g4 ~( K; D3 a
"road. Either increase the amount of roads ": x' m' \9 r4 `7 G C
"by increasing the GRID-SIZE-X or ", h6 X1 ~" G G) L% K8 h9 t g
"GRID-SIZE-Y sliders, or decrease the "
( h4 o9 Y8 C5 Z: @ "number of cars by lowering the NUMBER slider.\n"
( C; A! K7 Z; l# _3 ] "The setup has stopped.")1 d R; j. H$ j
stop; y( @8 N* ^. w, |! L% [
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 {" l; y8 Z5 [+ @5 |8 ^; r crt num-cars5 J% s8 i; Z/ l: K0 F# c' B
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setup-cars( e9 S" o2 `: X. l7 `
set-car-color, B2 }' @5 T+ H1 b3 G
record-data
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" T* O' z- o) ~( f3 v ;; give the turtles an initial speed" H" X; f% e/ G6 z ?3 `' Y
ask turtles [ set-car-speed ]. j N2 J! U* m/ o9 D% V; \
/ Q* o# {. S; p! P3 S reset-ticks' q* B+ R4 t: x1 P+ u3 H
end
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;; Initialize the global variables to appropriate values
" ~+ u+ {- ]5 X5 y8 Oto setup-globals! {+ K8 t9 s# ^, }
set current-light nobody ;; just for now, since there are no lights yet$ P7 h" C! J# e# T. k4 s
set phase 0
: t3 w. K) J# L8 ^: S set num-cars-stopped 0
* F [: Y* V6 m set grid-x-inc world-width / grid-size-x' M5 n2 K+ b" q% [0 a8 O
set grid-y-inc world-height / grid-size-y2 u) N O5 k" H: ]) H* z' `+ B
! y/ x# F* j# F! _1 O- _& d; D ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary& v* e, Q) C# L5 @) x, y @
set acceleration 0.0990 i) _- w7 c3 L6 Q
end3 Z1 j2 C0 G) o* C+ ~
% Q4 H# n' O3 z) {# a0 o+ q( I! D;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
" z, S J; D1 ]' M5 {# S;; and initialize the traffic lights to one setting( r* w5 |6 @- x r4 r) d
to setup-patches
8 ]: e4 D' ^8 J2 \! e* ` ;; initialize the patch-owned variables and color the patches to a base-color) l' \9 K: f' U. o/ {
ask patches
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" o: U2 a9 K' N$ ]: x set intersection? false& n' K0 c* l% T( y( ^; w, ~$ M
set auto? false' F- O0 ]; ?' i9 m* X& P
set green-light-up? true+ k! H5 L s$ J" i
set my-row -1$ \8 G* U) [( ^" o: y2 v* I
set my-column -1
' L" V/ ~$ M4 K& M) ~2 s5 u set my-phase -1
" R! A1 h+ Q7 g# d' O# @% y set pcolor brown + 3
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$ x; e \% o: Q3 g2 Z& \! j ;; initialize the global variables that hold patch agentsets& q# u @( w- q( i3 v- ]2 Z* Y
set roads patches with
" `% x8 r4 P, y; M' V+ [4 V [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. R& v9 J9 u( F1 p (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
7 |$ |$ J$ p* L set intersections roads with
8 D: u2 O: v/ x4 G( S/ A [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and: r$ J$ x: V8 [. u# P. Q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
! x+ z1 g6 j* H7 F2 ? setup-intersections
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4 p0 f- J5 g: p1 d其中定义道路的句子,如下所示,是什么意思啊?$ H0 h" n/ [0 `) u4 O
set roads patches with7 K! E- D6 m* x' Q1 @/ E4 f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 o; K' s9 e' R2 T( d7 c
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ G+ z7 X" U I" l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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