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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。( W' I, A& \: {7 p
netlogo自带的social science--traffic grid这一例子当中,
: M( w' _9 i. n8 X. Yglobals- Y2 w5 i2 Y; m i% T
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( V2 k( d2 j# Q/ I6 c grid-x-inc ;; the amount of patches in between two roads in the x direction0 ?. s1 M% D, [, g/ m9 d; E, e) l
grid-y-inc ;; the amount of patches in between two roads in the y direction
5 |$ h ^9 J3 b acceleration ;; the constant that controls how much a car speeds up or slows down by if
8 w& X- r! S/ v; {: d( p ;; it is to accelerate or decelerate
0 R8 e) a. L I phase ;; keeps track of the phase
5 s! \3 ?& L- x& d num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure/ E; z _" w3 S5 E
current-light ;; the currently selected light
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& ]) K3 k: v0 i5 b ;; patch agentsets& x' ?- u4 o# t$ }9 ^7 b6 A
intersections ;; agentset containing the patches that are intersections4 a9 ^2 M/ |) Y- v) K( R
roads ;; agentset containing the patches that are roads1 \* S: u% c( l' A8 {! q
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8 E3 @' f0 o9 Q4 X( s# [turtles-own
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2 \1 v$ T6 Y" X p2 h6 H. h speed ;; the speed of the turtle! o* F! u M8 U' ]9 Q) ?' O2 M6 F
up-car? ;; true if the turtle moves downwards and false if it moves to the right
$ b) C& d' U, m+ j# `9 j( o- k wait-time ;; the amount of time since the last time a turtle has moved
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, ~2 V; g* U) n6 n# {patches-own/ a! |5 n2 [; D4 ?7 a! E
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intersection? ;; true if the patch is at the intersection of two roads& }8 S% _( \9 [/ |
green-light-up? ;; true if the green light is above the intersection. otherwise, false.+ f o2 o; D' b+ @: ^% G5 C! ~/ k
;; false for a non-intersection patches.
% f& U8 ] b, R& }; s6 C& U: h my-row ;; the row of the intersection counting from the upper left corner of the0 { ^2 J! [4 z( E4 L5 x
;; world. -1 for non-intersection patches.
4 D9 G; @' m, a7 Z+ H" \. h% F my-column ;; the column of the intersection counting from the upper left corner of the
$ |7 o5 n4 t3 |" b8 l ;; world. -1 for non-intersection patches.
' H5 ~; ]8 I/ N! ] my-phase ;; the phase for the intersection. -1 for non-intersection patches.$ E: C0 e6 z1 h0 ~
auto? ;; whether or not this intersection will switch automatically., r5 P+ F4 c+ ?! |
;; false for non-intersection patches.% h/ V! X, ?2 T3 t# t- _3 M
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+ I* Z5 @7 r8 D# R5 i9 v1 _;;;;;;;;;;;;;;;;;;;;;;9 m# O, @+ P4 P% V" G1 D
;; Setup Procedures ;;
. g+ P6 b" A: T8 |; N: z;;;;;;;;;;;;;;;;;;;;;;: H$ A) k, H' s: S
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;; Initialize the display by giving the global and patch variables initial values.
+ K/ d# h3 S1 p9 y( g3 |& t; @;; Create num-cars of turtles if there are enough road patches for one turtle to* m; E* U) s+ r0 v) l
;; be created per road patch. Set up the plots." C! K" h Q5 }+ G: ?
to setup
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0 c; N: h7 } y1 i' o4 G1 E# L, v* E setup-globals
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; Z9 z" ^% z2 d0 z: p' o ;; First we ask the patches to draw themselves and set up a few variables7 n8 D, j* y+ T k
setup-patches7 D+ r d J& d+ U
make-current one-of intersections
0 O: I5 l$ |$ j6 ` label-current# z; i- J' ~' x' D/ r/ x6 d* w
+ `9 A* _* o; A4 T9 o; n/ F( T set-default-shape turtles "car"* A" ^# |, d- q9 s0 D" K
$ v- \ x1 ]" j8 i$ c9 P5 k, H if (num-cars > count roads) C8 Z+ s1 T# Q3 O! s
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user-message (word "There are too many cars for the amount of "
) o' K5 O0 q* Z* { "road. Either increase the amount of roads "' w2 J ^4 u. x/ h
"by increasing the GRID-SIZE-X or "
2 B7 M* v5 c9 F "GRID-SIZE-Y sliders, or decrease the "
5 X4 L3 w @& s2 ~% G* Q. z3 Q "number of cars by lowering the NUMBER slider.\n"0 ?; @1 z' c$ T# Y
"The setup has stopped.")
2 U1 d* n. k0 e1 k {9 t4 @ stop/ ?# J: \7 Y7 j) B2 o& X! h
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color# C/ g3 X$ e4 a' R6 h; \
crt num-cars9 s! v) ^6 y0 `* t
[
1 r8 {) ]. U* e7 i3 g setup-cars
' u) G6 x* I3 r set-car-color
/ }% Z7 c) K$ F* y8 i record-data
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;; give the turtles an initial speed" d7 u2 v$ W! E9 H2 a5 A
ask turtles [ set-car-speed ]
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reset-ticks% h8 M) {0 X! z* _ I4 x
end: k6 E [- d ^3 E: X6 \; O
& {; t0 y1 g4 O. B$ f;; Initialize the global variables to appropriate values8 E: l) C. x8 R: F, a7 z- t5 V! t
to setup-globals: k" i% W. M4 i
set current-light nobody ;; just for now, since there are no lights yet! f/ r. H, n/ O' V' X
set phase 0# F; z) @8 q; ~
set num-cars-stopped 07 n" x6 K: U# P: _
set grid-x-inc world-width / grid-size-x8 X9 @" z# b# g, C2 I" l
set grid-y-inc world-height / grid-size-y
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( X7 @$ S; M7 o4 Y. ~; A ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
9 X! M5 _5 ]6 x. |4 R set acceleration 0.099& G# x( u' k C1 E5 }/ n4 z/ R" ?! b# j8 m
end
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: z+ b7 ^6 \3 `% G. H" Y" e;; Make the patches have appropriate colors, set up the roads and intersections agentsets,' ? ?! v y' B8 v
;; and initialize the traffic lights to one setting
6 D1 m6 D9 s, V5 H$ jto setup-patches0 V7 ^' L( k" ]7 C* v- B
;; initialize the patch-owned variables and color the patches to a base-color
* v# E% _. R; q0 u+ P4 g7 O! k ask patches
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4 I0 Q' V- b7 b- Z5 f+ M( L set intersection? false
% j5 J) V7 F& o" B& n, T set auto? false
' p3 o7 h7 v+ {# y set green-light-up? true( R. B1 l% j/ X6 Q) R4 E! {2 E9 {
set my-row -13 H/ }3 f, Z3 @2 U& `
set my-column -1- X" t8 r. I" u% L6 B% @
set my-phase -1' j5 |1 ^' Z+ K. f( W8 \3 w! ]
set pcolor brown + 36 C/ ?, e4 N/ e, P5 A0 Z& j) L
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4 F; J" z2 r* L6 w& @, \ ;; initialize the global variables that hold patch agentsets
4 o) A- e/ T# z set roads patches with0 n7 t1 r( P7 M7 L+ |1 ]- [! e9 r A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 E+ _5 Q) N$ W/ o$ K! l (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
2 Z. K3 y6 h" y set intersections roads with# m5 f& T4 ^2 w1 R5 z9 G5 k6 K- M9 B
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and+ `4 x; t2 t1 G+ [# P
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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9 X3 x' n! |" @. Z0 t5 v* b ask roads [ set pcolor white ]! O6 J1 d% G C4 w- M0 E6 f: {
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
, ~6 K2 m/ n! t6 t* J: S$ z set roads patches with
2 B5 l2 b4 X. r, G3 X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
7 [5 z% x% ?4 K- X (floor((pycor + max-pycor) mod grid-y-inc) = 0)]: T9 E3 R- I6 a$ E; 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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