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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。
" ~- _* n3 H% q$ i' v* p" V0 s3 znetlogo自带的social science--traffic grid这一例子当中,
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grid-x-inc ;; the amount of patches in between two roads in the x direction
2 o5 b9 M- h- t. a8 x3 @ grid-y-inc ;; the amount of patches in between two roads in the y direction
& T7 [4 B- ?1 F acceleration ;; the constant that controls how much a car speeds up or slows down by if$ b( e, Y* Z, x( ~
;; it is to accelerate or decelerate
* p4 e6 L& K' ?$ ^% h+ n$ ` phase ;; keeps track of the phase1 G. x+ j2 r6 a$ f) t$ `8 H
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
- H K9 X, m" h Y" Y current-light ;; the currently selected light% M. K, k/ y2 Q* ]% B
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;; patch agentsets" U* S( U* E. C5 r) a# B. i# o* U
intersections ;; agentset containing the patches that are intersections( D, ]4 V7 B3 s, x6 F% K9 d4 ~: L
roads ;; agentset containing the patches that are roads* I- b+ M# O/ m$ L0 Y7 t% o; N
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turtles-own
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speed ;; the speed of the turtle
. ?: ~$ p) ]* a( n! h" @" M up-car? ;; true if the turtle moves downwards and false if it moves to the right
( h) ~( ^- E; Q1 ?' ^. v wait-time ;; the amount of time since the last time a turtle has moved
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! P$ X9 b9 X |4 X' [3 F# i" }/ ]patches-own
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intersection? ;; true if the patch is at the intersection of two roads4 i: z G, h- }5 k
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
; y( ~" K. G- F. Z. z' n% T ;; false for a non-intersection patches.
) ^$ v. V* k3 ^ my-row ;; the row of the intersection counting from the upper left corner of the+ A* m' U& d6 e8 K6 F2 b
;; world. -1 for non-intersection patches.! ~3 }# X' u) }
my-column ;; the column of the intersection counting from the upper left corner of the
1 Y4 Y! a, v; d* S ;; world. -1 for non-intersection patches." F! ]" _6 w7 Y
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
6 Y& g" |7 F) F, W auto? ;; whether or not this intersection will switch automatically./ Q. R1 W R& q6 g
;; false for non-intersection patches.5 t, G; j& Q1 [* y
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;;;;;;;;;;;;;;;;;;;;;;2 X% Y8 f+ l' \4 R$ B0 a
;; Setup Procedures ;;4 Z3 r T- H& s+ a1 R
;;;;;;;;;;;;;;;;;;;;;;
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4 C8 U( B4 X; F;; Initialize the display by giving the global and patch variables initial values.
. d+ a% z+ @3 P R;; Create num-cars of turtles if there are enough road patches for one turtle to
& }7 u+ F- {% i2 y;; be created per road patch. Set up the plots.# p# j" M9 q6 i5 U" ]/ W
to setup5 X0 H ?; A/ f4 {3 x/ ?
ca
$ b0 c% \7 f3 { setup-globals- A7 H8 @8 `4 l3 a: f3 p1 E
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;; First we ask the patches to draw themselves and set up a few variables: a7 [2 {2 q, z* t7 J* o& o' U# y
setup-patches
1 z# {# i+ R2 k. [ \! g0 w make-current one-of intersections
0 g) T L" {9 x7 p" Q! i label-current! g5 `' Z7 _% j0 V/ j: H4 a$ c% f( g4 q
3 C: _) w9 ? L9 j# F4 y O6 z set-default-shape turtles "car"! U; p1 o# P& t1 E. { r. C: z5 k
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if (num-cars > count roads)3 w& U' b- l2 \) w5 R8 W0 R6 o
[
$ ?, G- \: R& f+ x% Q user-message (word "There are too many cars for the amount of "9 ?0 V3 K: K" Z, R
"road. Either increase the amount of roads "
) }. v0 F# z) g8 _; Y$ l "by increasing the GRID-SIZE-X or "8 i8 [0 G b) D, Q
"GRID-SIZE-Y sliders, or decrease the "" E \4 E+ ~4 ^
"number of cars by lowering the NUMBER slider.\n"
/ a% h0 p9 O( |+ N. f! u4 G "The setup has stopped.")- i9 t" J3 [0 u: C& k3 ]
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
3 g k& c6 f, v0 n3 L" z crt num-cars
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- N2 l+ X! x8 \( W2 f! Q: N D setup-cars& k' ]+ K' v: d! d2 v8 q
set-car-color
6 @$ F# c# G3 T3 F2 R record-data
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;; give the turtles an initial speed7 y1 u5 ?% \0 z- Z, b
ask turtles [ set-car-speed ], [! U' |- Z/ Q; q
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reset-ticks
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3 G5 `0 G H" K9 f& ]8 ^, ?;; Initialize the global variables to appropriate values
3 {/ P6 o! Q4 p y- hto setup-globals3 O, ~9 G4 C4 D6 u6 [
set current-light nobody ;; just for now, since there are no lights yet
3 {- f/ X2 Q) k% v5 e u set phase 0
( i1 u1 }6 r$ ]' r set num-cars-stopped 0$ l9 t. T3 \! `6 O! \0 r
set grid-x-inc world-width / grid-size-x% e7 T! b6 v! k ^5 {6 h
set grid-y-inc world-height / grid-size-y
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+ ~# b8 J) I- f# S$ x ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
& ^' h3 Y4 d% `* r1 h6 ~; L set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,% v/ X* H+ k0 ^4 q! |: W
;; and initialize the traffic lights to one setting
, Q% B3 H, T5 D Q2 Q8 I2 kto setup-patches
7 O g+ |' L0 p3 ?4 I ;; initialize the patch-owned variables and color the patches to a base-color; ]* P. O! O0 U1 m: N7 x5 v
ask patches
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1 q3 D& m" p7 k r7 Q8 Q: T set intersection? false
- \# O4 Y4 {1 r; M! L& i; O set auto? false
/ f+ t( }" m; O' J# O& I set green-light-up? true
+ G( [2 w7 @' ~+ I set my-row -1
O# g7 H8 {! @$ V6 S set my-column -1
" u$ y! ^5 b5 D- z set my-phase -1* A# X8 m, ~/ Q: {! w3 u
set pcolor brown + 31 k+ j1 L4 e+ M; z3 w% U2 r
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;; initialize the global variables that hold patch agentsets4 \: I/ {! u0 }0 Y( D4 m5 C4 R r
set roads patches with
l' e# w* D& p# p- X+ z5 {$ o! f8 f [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, Q0 Z; i% n: v. y
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]! B9 @; Y7 i' a0 j3 ^: I
set intersections roads with
1 }: P" S$ ^ ^2 E' N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and% Q0 R) @0 C& v2 [) s4 ~
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
8 n! ?9 ~- k8 u' b 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?
% h% W! H7 a; x. N' c7 C set roads patches with. B8 i8 q, s. f- }% _
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
B* Q3 J- m& H) W. p1 ^! K3 } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' C/ w# f+ l( e# 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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