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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。, S& s4 x7 @5 s) C( O
netlogo自带的social science--traffic grid这一例子当中,
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4 D2 q$ w" x5 H; t* l; k grid-x-inc ;; the amount of patches in between two roads in the x direction
9 O, e, @ H3 ~" S/ [, P1 H6 Y grid-y-inc ;; the amount of patches in between two roads in the y direction
5 U5 C8 B% }) ?% @, \% W1 s; H* N acceleration ;; the constant that controls how much a car speeds up or slows down by if" Y$ o1 z; G) R* A- e
;; it is to accelerate or decelerate
& b4 }4 c1 d N( P* z8 w& b* E7 G phase ;; keeps track of the phase9 {2 n& l- V3 _& L, R( c+ h/ Q
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure2 |- F% q' P9 n! i
current-light ;; the currently selected light. l5 y7 ~" I5 q9 n- |
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;; patch agentsets
" b, G S0 o; {1 f7 U$ v2 k0 Z0 s intersections ;; agentset containing the patches that are intersections) h5 d# @3 O6 b% H6 c( c& f
roads ;; agentset containing the patches that are roads$ _0 p( s/ Z! y
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turtles-own
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speed ;; the speed of the turtle
3 y* c/ X* u5 I) h4 q) n" S up-car? ;; true if the turtle moves downwards and false if it moves to the right
) s, e$ @) F& y' i" M& Y wait-time ;; the amount of time since the last time a turtle has moved
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! @' c" y4 U3 F5 G% n8 jpatches-own
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3 _. X$ B) ~2 M intersection? ;; true if the patch is at the intersection of two roads
) C5 O' t' L, d. I green-light-up? ;; true if the green light is above the intersection. otherwise, false.' _; i" N6 s- z- S5 j' Y
;; false for a non-intersection patches.
3 x3 U% }8 f# b5 q) G my-row ;; the row of the intersection counting from the upper left corner of the3 S* L' D$ ~( Z8 Q. N8 C
;; world. -1 for non-intersection patches.
0 ^ N8 n; @# b; ?! S+ f my-column ;; the column of the intersection counting from the upper left corner of the. Q) X( D3 ]& y |( z1 J( p
;; world. -1 for non-intersection patches.
" |% [6 E) p5 G% L4 \, o: v" w my-phase ;; the phase for the intersection. -1 for non-intersection patches.2 \. x# f8 H* w0 O: o
auto? ;; whether or not this intersection will switch automatically.
n' ?# A1 P& _9 }/ s* f( K* F* V ;; false for non-intersection patches.. V n& y+ ^8 w$ a" K
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;;;;;;;;;;;;;;;;;;;;;;" w1 \, V0 [2 Z" J1 w
;; Setup Procedures ;;0 I7 V3 M- J8 o. ~& M. K" i2 ^. g5 V
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! E% l5 }: m2 Q; O6 q$ N* m/ V;; Initialize the display by giving the global and patch variables initial values.
5 p* w: i. f8 b; [;; Create num-cars of turtles if there are enough road patches for one turtle to
- k5 w; t9 E$ p H: I+ _8 J;; be created per road patch. Set up the plots.4 [2 n7 B7 Y4 W5 r* H; I
to setup+ O4 g" }, @4 T6 N: ]8 L
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables' K0 d- y" a& q$ Y
setup-patches) P9 X) h8 q5 j) S7 J
make-current one-of intersections% T6 E: ]5 K2 G- k. X
label-current
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; T# Q5 Q1 a; P& a set-default-shape turtles "car"4 A3 J3 p) r$ C
" @. J0 ~* K7 D8 m- T( w" l if (num-cars > count roads)5 d0 X5 H4 m* \5 W8 g
[5 {& J# S' N& f" u' }
user-message (word "There are too many cars for the amount of "
2 J* X1 ^' G/ z4 E$ G "road. Either increase the amount of roads "
p. m4 l4 ?( V! k& R "by increasing the GRID-SIZE-X or "
* h8 o8 o& N( ]8 M& J6 n "GRID-SIZE-Y sliders, or decrease the "; {2 t4 f2 `5 n) V
"number of cars by lowering the NUMBER slider.\n"3 h% N5 K' j7 ~# j6 {+ f
"The setup has stopped.")2 r+ u+ j. n6 j/ L; K% r, s
stop
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3 a* m( |7 F- D: w/ f ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color) y" h6 e0 k: S) N
crt num-cars. Q9 }9 s- q/ x+ d$ \7 |+ Y
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setup-cars
/ I( _8 U' G8 I' d$ V# n, C7 u9 W set-car-color
( G) N i- {6 g+ K; J ~) S record-data8 u8 R2 N* P/ V3 |1 D$ v
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0 A: o, W$ j8 u* [9 S* U5 K9 b ;; give the turtles an initial speed
. i$ s% P0 y: t4 U+ k. r9 s: o" O ask turtles [ set-car-speed ]* J8 ]% u2 A2 A0 i. l6 a# N. B
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reset-ticks$ i4 o9 }, S0 J* o
end) b# g% ~2 V( d3 W% A6 K1 E% n" U1 |! Z
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;; Initialize the global variables to appropriate values
. ]" _% g E% l+ m. }to setup-globals
1 L9 \$ G6 P. |* D# _9 f% y/ Z" @ set current-light nobody ;; just for now, since there are no lights yet
! v4 m T, u E# c set phase 0
; p" I7 j; B/ W% W) \ set num-cars-stopped 0
8 r/ a+ E9 [' I# e set grid-x-inc world-width / grid-size-x Z1 R9 G7 v$ ]/ r: p1 K
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
. V% _6 r& a. E. r6 R set acceleration 0.099
# B) F0 J+ f: n; [end% W1 A, q$ b3 e- r4 D
; E* S) c" i0 J) P;; Make the patches have appropriate colors, set up the roads and intersections agentsets,6 |0 ?/ K8 q/ s" T2 n" ?
;; and initialize the traffic lights to one setting' ]9 e& h& L" ?6 g
to setup-patches: k- l s: J# d! x1 B+ x, U
;; initialize the patch-owned variables and color the patches to a base-color: ^* u) O4 I9 q4 R0 J# @( T/ H+ U
ask patches3 Q+ J" \( A% |6 I) c
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set intersection? false2 c3 c1 D! u7 ^' I8 n
set auto? false& d0 Y$ R) |0 b7 \9 [
set green-light-up? true
$ a, s+ w5 U% w0 L8 h0 N" c set my-row -1- R I5 Q. z" r. S6 ^8 D& c9 S
set my-column -13 w6 Y% @$ {: @$ l* l
set my-phase -1
2 r3 u6 p0 a; X8 I set pcolor brown + 37 S; C/ N4 U& z8 |
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# i& N" g" b, o% r, R, ]- W( r! r ;; initialize the global variables that hold patch agentsets9 `' N) u1 c/ Y m& a8 d
set roads patches with
! }' `* U v0 I) v [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& j# k# A# L9 u$ ^8 m) q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 n4 o- n0 F- I- _ set intersections roads with
; r! v1 B& K# c; c$ \ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and; x: S' w+ d5 f, p* v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]4 J Z8 B. ^. A5 s0 ?
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?
0 i5 A& P1 w9 k: K set roads patches with5 N" E, z5 c V: @
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 L4 a- f0 s- ~+ q5 ^) [5 M (floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 G- @* h. b7 [$ `8 I, q
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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