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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。
4 G/ P0 k( L3 j- [# i8 L! qnetlogo自带的social science--traffic grid这一例子当中,
h/ T4 @" s" h% L0 ~globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction! l* ` T u; a% m
grid-y-inc ;; the amount of patches in between two roads in the y direction8 R% i1 D9 ^: m& b: O, M
acceleration ;; the constant that controls how much a car speeds up or slows down by if
$ H% g! ~0 {- I! g$ Q3 Z4 r; } ;; it is to accelerate or decelerate
# Z' l1 l/ Q1 C4 l5 H5 n phase ;; keeps track of the phase
; ^% Y( D# t7 l num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure) O& V) }/ P3 G$ r: _9 E8 S
current-light ;; the currently selected light
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: v X9 {3 Y, m: L ;; patch agentsets1 c6 L/ U6 K0 Q: ]; M5 {
intersections ;; agentset containing the patches that are intersections
5 S7 L) o8 ]3 g7 U5 T roads ;; agentset containing the patches that are roads* s6 T3 I' Y! B; T5 }. f6 ]
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: i7 I5 n. W- x3 F+ ~turtles-own9 y0 I M+ ^/ x8 d; _6 H6 i/ B* n
[
A$ @- e9 Y' |8 M9 W5 F8 @- \% e speed ;; the speed of the turtle: ?; y5 t s; M. j( k
up-car? ;; true if the turtle moves downwards and false if it moves to the right, N2 s; Z" f5 u0 j
wait-time ;; the amount of time since the last time a turtle has moved3 q* C4 s7 k& Z6 s& k$ {5 ?* b
]
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patches-own* O$ R- b( a/ O( }; L0 e. w6 z, }
[
7 }, T4 h- |: \1 y# S& q intersection? ;; true if the patch is at the intersection of two roads, I# B5 o6 A; t) C6 I+ y8 ^
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
& T, S& F( x3 F ;; false for a non-intersection patches.
* [' y' V: x7 Y my-row ;; the row of the intersection counting from the upper left corner of the
' j/ @+ `. Z, M$ Y/ C, y# g0 W ;; world. -1 for non-intersection patches. J9 V2 o1 \$ { f5 a8 x
my-column ;; the column of the intersection counting from the upper left corner of the
: ~0 S0 R. S3 F ;; world. -1 for non-intersection patches.+ s! `, y0 v# D* n6 l
my-phase ;; the phase for the intersection. -1 for non-intersection patches.9 O/ I1 @1 Z Q
auto? ;; whether or not this intersection will switch automatically.3 W, N* h+ p. R
;; false for non-intersection patches.
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4 d) n6 r: k x5 t8 s. C( s( K;;;;;;;;;;;;;;;;;;;;;;
Z- a! Q* t5 y6 K" t;; Setup Procedures ;;7 ~( p1 j" t# w5 s4 p, o! b1 l# ]
;;;;;;;;;;;;;;;;;;;;;; J8 I( Z- p. F) A( f% ~
/ w! @5 u1 y7 `+ i1 H4 r;; Initialize the display by giving the global and patch variables initial values.( L: F6 ~: K3 q
;; Create num-cars of turtles if there are enough road patches for one turtle to! Y' n. Z3 z2 d" j0 v4 L2 |
;; be created per road patch. Set up the plots.
/ K4 w( z5 O, Q9 U- i1 X/ u# `/ ]to setup, v- E. F- ?+ B! R
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setup-globals" Z! N, Q! s. T
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;; First we ask the patches to draw themselves and set up a few variables% ]. m o3 H- T$ m) a
setup-patches
. Z( S7 T3 j" m6 j( n make-current one-of intersections
* e$ D) f/ H2 D# T label-current
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set-default-shape turtles "car"
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- e' b: V" I, P' A: i6 m$ L if (num-cars > count roads)
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/ N6 Z8 ]" _' `# i7 |4 r! O1 j+ A A A user-message (word "There are too many cars for the amount of "
9 K0 n1 u4 l; H) g+ `% A "road. Either increase the amount of roads "
! E s8 G$ |, i, k "by increasing the GRID-SIZE-X or "
* Z* j) @ `5 C1 {* ]1 B& ?; W "GRID-SIZE-Y sliders, or decrease the "9 p0 Z3 w6 u5 f" l" p9 h- \
"number of cars by lowering the NUMBER slider.\n"
9 X! I8 K) \6 O+ K) w "The setup has stopped.")
' [% P9 ]4 u, k8 k. q; D stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
# H w3 q# ~2 o crt num-cars- w# J9 L7 b; ^9 i$ s
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setup-cars; ]3 _6 a, W' X1 J" p+ O# t' B
set-car-color+ [7 j, E! z$ c) G7 ^5 y
record-data$ W) i. E' n6 Q: B6 q6 c1 \2 e
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;; give the turtles an initial speed
$ A* |7 u0 e; v) w8 u ~ ask turtles [ set-car-speed ]
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reset-ticks' q5 U8 ~" ~& D" S% z
end
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;; Initialize the global variables to appropriate values. j3 X5 c! p$ x
to setup-globals* O6 D3 |& U) t1 f5 O1 X- e' q5 c9 W
set current-light nobody ;; just for now, since there are no lights yet: I7 ^& I$ X) F5 U0 z9 w( f% [
set phase 05 R; V: e5 D: W9 @2 l+ T
set num-cars-stopped 0
9 H. i. b& I9 R$ C+ Q4 Z set grid-x-inc world-width / grid-size-x# a1 g2 M8 k5 y% X% h7 } k
set grid-y-inc world-height / grid-size-y
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- I# S5 |( u( s% M8 k7 ~7 ?% l ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
8 |$ A) K I& t9 W; m set acceleration 0.0993 I U5 T; y+ f$ j' B6 C: J
end8 G' ]1 [! {7 L! B- l* k
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets, P3 G' [ i. e1 f" H Y
;; and initialize the traffic lights to one setting/ D% Q* t D/ k
to setup-patches5 z: S! _2 z2 z: k" n( p
;; initialize the patch-owned variables and color the patches to a base-color
3 \% |6 E( V+ f3 M! j0 k/ V. T ask patches: }2 {: k, R1 {4 V3 z+ o' l
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set intersection? false
+ |1 Z z4 L$ m# y- \ set auto? false
2 a8 n( R; Z: { set green-light-up? true1 d6 q' w: l8 n; U! P7 r' M' K
set my-row -1
4 ?1 }- S* l0 t, {6 P9 H7 a2 X set my-column -1$ o/ a9 H: J) Q; Y% B! E0 ?9 s
set my-phase -1
, d# z# V3 |) Y+ P* b+ v5 V) }1 c set pcolor brown + 3) U0 `4 @2 z9 f$ X& m8 I
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6 ^$ @" l$ B9 M7 A U# ? ;; initialize the global variables that hold patch agentsets
7 _+ ]6 i( E3 \5 K) \ set roads patches with
0 s, b7 g+ B% @* D0 E: y5 Z- a [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* S& o; S: c; }4 j: N$ }- M (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# w) L) R% R! j1 A( S4 P
set intersections roads with/ [1 A" \ `+ C# N% `
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 F% [' D; x$ j8 F3 y
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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+ u5 q6 n6 }, T- ^ ask roads [ set pcolor white ]# }0 x5 J0 a8 `( z3 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?" @2 D# {% m7 f: g
set roads patches with: U0 u$ \3 d# j8 e' m8 Y
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or I' H7 J" |9 G c/ a8 i
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]! C4 N1 ~" j$ ?# ], Z# g8 m% b- X" D
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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