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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。
) k, N* B& r( r5 M2 p2 rnetlogo自带的social science--traffic grid这一例子当中,; ~; }, W) ] U/ m& O
globals: C6 W- J/ W: _& D
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7 H( h/ Z) }2 t- k! ` grid-x-inc ;; the amount of patches in between two roads in the x direction
( B# R. C* I B5 Y grid-y-inc ;; the amount of patches in between two roads in the y direction2 M8 e) F6 _9 L/ ]% q" a5 a4 B
acceleration ;; the constant that controls how much a car speeds up or slows down by if, _1 y) P7 ^# v9 H% z* W) F1 R
;; it is to accelerate or decelerate
" R) |& ?" `8 L# b' L phase ;; keeps track of the phase
, _) J. n3 d# z( z/ N num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure1 s. j) v- i l C2 n7 U }0 N5 }; G
current-light ;; the currently selected light- ?% Z. ~9 c7 F- }
# q% v6 b) ?. O, J8 N4 M1 S ;; patch agentsets
* W; E3 }; a0 C, L, b ~& e6 y* P- Q intersections ;; agentset containing the patches that are intersections
6 B# H* s8 y# c+ M4 X7 h roads ;; agentset containing the patches that are roads* \) M4 x9 E1 X
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b9 g% A0 q u6 u9 g% Bturtles-own
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speed ;; the speed of the turtle/ U! o8 n. V: g% |
up-car? ;; true if the turtle moves downwards and false if it moves to the right# R9 }" ?4 A) U
wait-time ;; the amount of time since the last time a turtle has moved
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0 B$ z5 l" U' }patches-own) C6 F F6 f) N3 O, c7 [9 ?* E" C D- w
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& c/ A m H- H# t intersection? ;; true if the patch is at the intersection of two roads1 O6 H s7 z( D
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
( A1 o/ v+ P8 u" d& b, v ;; false for a non-intersection patches.* m2 U( \' L+ U1 G( l
my-row ;; the row of the intersection counting from the upper left corner of the$ q+ s1 N. s; J
;; world. -1 for non-intersection patches.
1 p/ s* q( E3 Y" I' E! X my-column ;; the column of the intersection counting from the upper left corner of the" k) ]. a: M. v$ |& E' j
;; world. -1 for non-intersection patches.
- q! t- O z6 o8 s# F& { my-phase ;; the phase for the intersection. -1 for non-intersection patches.
u9 V( Q' c4 c* s9 ?. O- W auto? ;; whether or not this intersection will switch automatically.
7 w4 ^* |& @7 C ;; false for non-intersection patches.
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0 l# V; j+ z$ E! H {, F; ^;;;;;;;;;;;;;;;;;;;;;;
7 U# v+ n' q& z; `- P+ O( H/ x# o;; Setup Procedures ;;
2 |$ Y. y7 k4 A; l+ b. M;;;;;;;;;;;;;;;;;;;;;;1 |: x i+ F9 a% N# n |8 o o
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;; Initialize the display by giving the global and patch variables initial values.+ `/ o4 C8 h# Q. C
;; Create num-cars of turtles if there are enough road patches for one turtle to
# C% T4 ?' _* R;; be created per road patch. Set up the plots.
& d5 a. V. A$ Q# r+ uto setup# p( s5 w/ C4 @
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
, v6 G6 q4 o8 E- T# J- t setup-patches* i2 m5 A; ~$ J; {! S
make-current one-of intersections
' N, A5 D7 v7 z9 R1 W% a label-current
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, U7 z4 S- _3 e3 O: R$ Z0 Q9 T set-default-shape turtles "car"
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if (num-cars > count roads)6 {6 `7 H% m# c( t; `- X5 N
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% g, y+ _3 A) s6 e9 d4 K& C" W user-message (word "There are too many cars for the amount of "$ V# [% K7 |" I, a4 q# M. ?
"road. Either increase the amount of roads "
2 S8 T+ T1 V' v$ E "by increasing the GRID-SIZE-X or "
" b B" X/ o1 P! a# Y3 } "GRID-SIZE-Y sliders, or decrease the "+ ]+ E3 ]! j. o
"number of cars by lowering the NUMBER slider.\n"
, q* n+ R" \0 S4 f "The setup has stopped.")
4 v% k1 k( r( J% l. W. f stop+ ?% h( z: |6 i$ a P2 K. [
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color% D( c$ o. D/ l
crt num-cars
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setup-cars
9 D0 x J* h% N: _ set-car-color+ i' h8 n. E3 T+ Q7 S6 M6 V
record-data
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;; give the turtles an initial speed
" L l8 _# `5 B ask turtles [ set-car-speed ]
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! i# M' `5 M; U! \( \: P6 [0 n" Z reset-ticks
2 E- s3 @. \+ w+ x& Z2 u9 Nend
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;; Initialize the global variables to appropriate values) p1 h: |7 A W4 n! m
to setup-globals
. a/ O, e6 |. h* \: H6 J8 b, F1 c set current-light nobody ;; just for now, since there are no lights yet& ]$ ]1 k3 y* G: {" o1 c( H
set phase 0
( J" t+ O# }2 T& o: C! v set num-cars-stopped 0
- o: p1 W8 V4 L- Y set grid-x-inc world-width / grid-size-x
7 W. {4 P8 D8 w* E set grid-y-inc world-height / grid-size-y; v0 d9 @. I3 G. {0 c7 t' ^' u! O
6 e8 F% |1 P5 }" r" ~& U, e4 F ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
) M: s0 c4 Q$ z. o5 Z+ F, O/ m% } set acceleration 0.099
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: t* Z! e- b6 X y- w K;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
) W* `+ }9 e) n- w! y: q e;; and initialize the traffic lights to one setting7 j, h( z' Z: H6 y$ m: s
to setup-patches1 @6 i, K# @! I4 H# u* T/ H
;; initialize the patch-owned variables and color the patches to a base-color
2 D% ] S( Q+ | ask patches6 n8 n5 A* }" C- e# U/ d* A
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set intersection? false: h+ `/ O. n5 m7 D! p
set auto? false) Q: V. F: `% l* p/ z+ _$ O! @7 f
set green-light-up? true
+ Q6 j+ f9 R! I2 w* I% l set my-row -1
- e$ n# g6 m3 V( i+ M$ Y set my-column -1" x% P, j1 ]" h) ^. F' i3 M# t
set my-phase -1
4 J5 C9 K2 ~# _4 w# U ^ set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets) u) G2 q' \' @# K7 s+ E* W# j
set roads patches with0 [* [/ p5 w( S0 `! R3 J2 Y2 b
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* n( {; b+ w- C (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
6 H* c; i4 _( m set intersections roads with* B m& y6 j/ L; h1 V( A0 i1 E: Y- o: f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, H0 k! A5 _& h9 _ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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: @. K. Z2 K5 m2 }! _3 l& Z. j$ H2 a ask roads [ set pcolor white ]
( ]/ k( L+ C* j! a setup-intersections6 p# l. q$ G. [# R! a- A2 E
end
. |& X4 t ~, B其中定义道路的句子,如下所示,是什么意思啊?
, V( R3 V# n( z+ X E$ C set roads patches with
' n% x' q8 o2 K [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
8 [* Q t9 K. |4 D; k( Z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" d6 j5 Q F9 U8 l: m/ s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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