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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。: e1 A/ W, O" ~
netlogo自带的social science--traffic grid这一例子当中,
3 a0 H, I( Q2 c5 H; X, Xglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction$ O7 r1 p. y) b. i
grid-y-inc ;; the amount of patches in between two roads in the y direction8 u/ I8 s Y& Y" \" ^
acceleration ;; the constant that controls how much a car speeds up or slows down by if
) K1 C& d! f/ ]! Q2 i ;; it is to accelerate or decelerate
7 P9 J$ m0 O9 y$ U2 k @ phase ;; keeps track of the phase
: q: }1 j9 m- L- u' |* T* O$ q) E num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
" l, ]1 M* [+ z M/ o current-light ;; the currently selected light
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9 e) A* J- Z: d, S: i* m ;; patch agentsets" K: M: F6 s; @' v9 H, J) m/ l
intersections ;; agentset containing the patches that are intersections
3 ^% Q5 Q$ w, U roads ;; agentset containing the patches that are roads! x+ F% V" E' ^) C+ x/ u' ?
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turtles-own
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/ e1 b3 Q8 J+ B" m J speed ;; the speed of the turtle
' | N+ Y& A5 _; O* M/ U L9 c: W up-car? ;; true if the turtle moves downwards and false if it moves to the right. k( I' \7 L/ z; J# O
wait-time ;; the amount of time since the last time a turtle has moved
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- t( D! t% w9 I9 Npatches-own( s' t( Z" \4 J" b' j* u+ Y* Y: q- g
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$ `0 X$ N6 ?0 \4 X$ W8 c3 X2 N intersection? ;; true if the patch is at the intersection of two roads. R. C$ l; O) X/ S+ W4 r' t
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
) o! E% K. z0 T ;; false for a non-intersection patches.
0 q. v, F2 g* w my-row ;; the row of the intersection counting from the upper left corner of the% O/ p8 ?9 S, B- \+ \& D2 S
;; world. -1 for non-intersection patches.5 Q% P h) D9 i# L4 S4 C
my-column ;; the column of the intersection counting from the upper left corner of the
% ?2 |4 M0 e% f; c& n: ^, B3 Q! e ;; world. -1 for non-intersection patches.
. f0 ]3 M8 P& ?; j: t7 T) f my-phase ;; the phase for the intersection. -1 for non-intersection patches.
9 E" B% y9 K2 u( E- u7 n auto? ;; whether or not this intersection will switch automatically.+ M `: |( G* \! P3 G' V0 a5 z& O
;; false for non-intersection patches.& u9 c+ S C. `/ ]
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0 p+ e( _: ^; f' z;;;;;;;;;;;;;;;;;;;;;;
& l6 b/ `! L4 c% \3 r4 z;; Setup Procedures ;;5 b" o; y, x; z' |- |+ E" J
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.; p( H/ k9 \; G5 O4 ~9 c
;; Create num-cars of turtles if there are enough road patches for one turtle to
, y2 `8 F4 `' D* f;; be created per road patch. Set up the plots.
3 R- _6 J3 v3 S. o4 i; Gto setup
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setup-globals
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8 w w% L5 W$ o0 ]' ~( N$ d ;; First we ask the patches to draw themselves and set up a few variables
- j7 E' [' H. F! b setup-patches
/ H/ `" Z3 x* y9 j5 b& ~" Y make-current one-of intersections. U5 f! }2 B; A7 |4 a/ W
label-current
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set-default-shape turtles "car"/ J: l6 P1 w* I
# W0 d) [( W! n if (num-cars > count roads); S& b* B6 x+ d2 L( Q0 P
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% W( o; j3 L6 N4 T3 |8 w user-message (word "There are too many cars for the amount of "5 A) w( c0 t8 @9 D- D8 P
"road. Either increase the amount of roads "& U7 b- |6 a7 J% ]; B
"by increasing the GRID-SIZE-X or "
/ p. s: O0 v: m# i* `. A "GRID-SIZE-Y sliders, or decrease the "4 P% v! H9 d6 Y6 G
"number of cars by lowering the NUMBER slider.\n"% f. {) _$ D$ U5 p$ B
"The setup has stopped.")
8 t7 W$ v. C. d \ stop
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9 a' l0 ~$ ?. D% D3 _% S0 _ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color2 x6 a% s5 t4 I$ ~, }" i
crt num-cars# V+ A1 X* {6 U+ [# \" q
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2 E& A" j2 w8 m4 I3 C& ^/ t5 V3 L setup-cars
4 F0 N/ N/ c1 o; C5 u, c set-car-color
5 b' x& I. T' g0 u: c5 M7 T- Q record-data
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; ~) A6 }% y; N. b ;; give the turtles an initial speed
6 N( d% t' A3 C# |. C4 A% E8 ^' l6 l ask turtles [ set-car-speed ]
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) l9 H2 W, {. q8 C6 { reset-ticks! v' R! h/ E' J$ J1 P
end
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8 y9 h2 b' C3 s% S;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet; s0 [3 Z N3 d! g2 |5 p
set phase 0/ T6 o" m5 C; v" y9 T5 U* P
set num-cars-stopped 0
D+ e! d+ C: k+ J! N# d0 ^- t) W set grid-x-inc world-width / grid-size-x( p0 G2 z z* J
set grid-y-inc world-height / grid-size-y
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: {7 F. X$ s- @5 S: r' Y ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
6 [! j# z2 A8 |* ~( F3 f set acceleration 0.0992 Z' u, r @! N4 U
end+ N# T f" s( }& e4 z
& ^9 p; v/ ]: P. g# n8 \9 @;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
; Z+ ?/ c( _, }9 _;; and initialize the traffic lights to one setting) S) r# D' g0 N+ G
to setup-patches9 Y0 b% q2 f1 E- A( q5 t5 _6 r2 z+ g
;; initialize the patch-owned variables and color the patches to a base-color
7 ]) Z- Z& h# G+ ~ ask patches: Y1 P' }/ n3 B
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set intersection? false1 ?$ O- N( w3 ?! ~9 f9 V
set auto? false
0 b- t* ?; s3 s: N( ? set green-light-up? true) W1 x. [4 E$ r- s8 [
set my-row -1
" x- ~" Z" Q/ N5 c3 f O5 E set my-column -1. U; }( j8 P- p) x# h0 r* `
set my-phase -1+ E: ?- v8 B+ }- ~1 j
set pcolor brown + 3
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( ]8 _0 m# L; c& F ;; initialize the global variables that hold patch agentsets
2 T/ }" \" K4 k6 u+ _/ X set roads patches with) O C% i3 ?- S( A7 v
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- W; E0 r9 {, u$ t- }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ ^, m" a: e( F- A( B# K* |' t set intersections roads with9 Z5 d8 P3 }# ^* I/ f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, I9 I5 n! y8 k: l+ d5 k (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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4 W) J. m3 F, S& E1 \ ask roads [ set pcolor white ]
9 r, o: \3 Q' _/ k1 e 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?( b1 N! E9 S, ?7 o h" E0 H
set roads patches with
3 Z) F% F% B, A b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; n& K0 T0 e' _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]; X4 F/ _+ g5 m! c
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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