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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。
. V5 @0 G; f' j9 inetlogo自带的social science--traffic grid这一例子当中,
/ P3 n& K! x1 L, f! w; cglobals
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! d5 y( ^" q |9 R( G' q grid-x-inc ;; the amount of patches in between two roads in the x direction7 `7 \3 N. C! v G$ O' _# _ x. q% h
grid-y-inc ;; the amount of patches in between two roads in the y direction6 R6 K" Q, L+ R
acceleration ;; the constant that controls how much a car speeds up or slows down by if: }$ P. c- T& P+ w& @ q2 R) _
;; it is to accelerate or decelerate E7 ?+ k) _3 d2 D
phase ;; keeps track of the phase
3 `" @- s/ |, V8 h) O4 K num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" X) @; E4 \3 i
current-light ;; the currently selected light2 F* v) f1 w+ ]: A* Z
- H: k+ {2 {4 m; P1 t ;; patch agentsets0 \: {& `. l1 f2 q) }' a3 S
intersections ;; agentset containing the patches that are intersections0 ~( G4 I, ]' C
roads ;; agentset containing the patches that are roads
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turtles-own3 d' @# |% z& L- s9 M
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speed ;; the speed of the turtle$ x5 W# M y8 t% z8 a6 N
up-car? ;; true if the turtle moves downwards and false if it moves to the right
% ?0 o: X- ~/ `& w wait-time ;; the amount of time since the last time a turtle has moved
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; G2 C7 l# n5 C' c5 [; ipatches-own+ M v$ O8 L* h, u) K
[) e. A! U. b. N. R
intersection? ;; true if the patch is at the intersection of two roads
' c& D6 `: M7 ~7 a! x) T8 D green-light-up? ;; true if the green light is above the intersection. otherwise, false.
6 q' P8 @& ~' v& f. B- ]" ` ;; false for a non-intersection patches.4 [$ M( C4 B& s) l$ P
my-row ;; the row of the intersection counting from the upper left corner of the% x5 X$ S6 s0 f8 C4 ?& F4 y/ i3 c
;; world. -1 for non-intersection patches.
. m1 S4 |6 E$ C- B- ^ my-column ;; the column of the intersection counting from the upper left corner of the
$ i0 B) i3 b. h9 M ;; world. -1 for non-intersection patches.
1 e/ \; [1 b; }& ~& }! m. L0 ^ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
: S0 g0 M3 v3 L$ X) R' x m auto? ;; whether or not this intersection will switch automatically.5 Q8 b" H' @2 Z4 ^
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;" x! I% ]7 k2 |2 X0 g) F' p
;; Setup Procedures ;;7 G+ s# d7 n' y* T5 z0 Y
;;;;;;;;;;;;;;;;;;;;;;
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9 l, `1 K2 g: r6 b;; Initialize the display by giving the global and patch variables initial values.
) O5 r6 o \1 c: e' P;; Create num-cars of turtles if there are enough road patches for one turtle to% W# T7 z: _9 d
;; be created per road patch. Set up the plots.# B* e5 S/ ^2 P- H" b: G
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables/ d& M1 k* y( N
setup-patches
9 U0 C) Y9 i( z, Q7 s* u make-current one-of intersections
% w* l/ \+ G- m+ V label-current' v6 F! W, ?6 _4 w8 i( \: I9 e- u
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set-default-shape turtles "car"
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if (num-cars > count roads)' y" y( X$ {+ |
[
* ~ x/ m8 g M5 N d2 Y9 S user-message (word "There are too many cars for the amount of "$ D& J" Z1 ?3 s* ^) X
"road. Either increase the amount of roads "3 c: j# G8 O# e* _! H
"by increasing the GRID-SIZE-X or "1 n0 L1 O% h! O$ q5 J
"GRID-SIZE-Y sliders, or decrease the "
& p7 o8 {4 Z C "number of cars by lowering the NUMBER slider.\n"7 ?4 N! s8 V$ z4 y' s% T
"The setup has stopped.")
. C- p3 j4 j. j3 m* b2 t/ O stop1 \" ~, D, p% j/ T' T: W
]
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color5 X7 `& x' H/ D2 L8 ~2 v6 k
crt num-cars+ \; V3 I. o3 \ I! \7 N( L
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setup-cars3 |1 @7 S% _, v" K
set-car-color) E5 ]( S5 I0 M& f/ j E% I! d
record-data
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;; give the turtles an initial speed
6 x; J- }. O5 \% _ ask turtles [ set-car-speed ]+ ~6 r0 o( ]. W
+ X d0 g7 A- Z/ \* w+ u reset-ticks o/ e* h6 j% O, h9 E
end8 z/ P% @3 M, a/ ?1 z& r
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;; Initialize the global variables to appropriate values' |5 c& U; U( r, U" j1 C7 I/ H
to setup-globals0 e: y/ F; U% m6 O
set current-light nobody ;; just for now, since there are no lights yet
: M2 }2 X( J1 e, @: N' W( h set phase 0
5 T+ q+ u# V) @ set num-cars-stopped 0
; G5 W# C+ m4 b0 j' M0 E# N set grid-x-inc world-width / grid-size-x
0 P: i( B l0 K7 G) A3 W9 X set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
) J* J3 w) J& Z4 m& b% [4 | set acceleration 0.099+ e1 ]4 S g$ N) O
end
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# d7 N3 M7 `2 M# I/ [;; Make the patches have appropriate colors, set up the roads and intersections agentsets,' K9 w ~7 Q* y* L
;; and initialize the traffic lights to one setting
2 i: z2 @' |9 Kto setup-patches6 {. x4 A# l2 d& p+ C; a
;; initialize the patch-owned variables and color the patches to a base-color$ h5 t. E: ?' l
ask patches# n/ R6 z7 i, N8 O- |
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set intersection? false8 `; X K& Z* F/ {. s o, H
set auto? false0 g5 @( a6 O0 P$ w; g" G6 X
set green-light-up? true
: x! Y4 ~2 F1 H set my-row -1
w) S; H9 J8 \9 i. e* K0 n9 ]* a set my-column -1& D" e0 u2 D, b, ?+ A- g
set my-phase -1
( D* M4 \ _' q( n/ s set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
) B9 b/ \7 G+ f- `, F$ h8 { set roads patches with: ^+ A+ v/ ]% T, f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
! I4 R P+ A: l. {2 n: {. ` (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 r4 O' E, O! |
set intersections roads with
$ A% H: `2 z, f E& B! }* A' B) O) Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
1 [( s. _( p, V/ m2 ] (floor((pycor + max-pycor) mod grid-y-inc) = 0)]) ]( \' h% ~8 e, ]+ {
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ask roads [ set pcolor white ], H1 g- r: f6 M0 M
setup-intersections- l5 ^( O: _" E' c% Z- J! |
end3 ^, O8 K' t7 ^) T8 P, J
其中定义道路的句子,如下所示,是什么意思啊?
; f1 }( t; r5 S. ~ set roads patches with* B! W3 @+ S/ m; X
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. ?) `6 J, P) [ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]# C) S' x. M/ y* _2 ^$ J9 W
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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