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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。
9 ~2 r. p8 u* R! o% }netlogo自带的social science--traffic grid这一例子当中,
5 I5 v* P/ D v' a& h8 Qglobals+ \/ w3 z! v, k
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grid-x-inc ;; the amount of patches in between two roads in the x direction5 R. Y( E0 c2 t2 `& {6 p9 F
grid-y-inc ;; the amount of patches in between two roads in the y direction) [1 F) p- A Q( S. I1 a0 P/ q
acceleration ;; the constant that controls how much a car speeds up or slows down by if
8 r+ W' u: _) x- Q5 S# F ;; it is to accelerate or decelerate+ w) ^' @, S8 u \4 k0 u) f
phase ;; keeps track of the phase1 }- {6 R/ l$ h& O9 Y
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
' c0 X" ^8 J; y+ W( q current-light ;; the currently selected light
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;; patch agentsets
1 q7 D! L- S, ? intersections ;; agentset containing the patches that are intersections2 ~5 [' z, `. }* q
roads ;; agentset containing the patches that are roads8 p$ L& I; ?+ W; v9 W; E
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$ y; I. _" M4 Uturtles-own
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speed ;; the speed of the turtle
3 o1 z) i4 S: W% f( p" d up-car? ;; true if the turtle moves downwards and false if it moves to the right
& \4 u7 [; t6 y2 R3 B t. T5 @7 Q wait-time ;; the amount of time since the last time a turtle has moved
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patches-own9 z' `, q. h) c: @% P& ~3 {
[
9 S# w# P( B, i2 I4 G( J5 ~3 B intersection? ;; true if the patch is at the intersection of two roads- x/ G$ l( z" f# v2 t& Z5 w$ w
green-light-up? ;; true if the green light is above the intersection. otherwise, false." A n6 Y3 z: e) [ i# c* \
;; false for a non-intersection patches.
! O* w) n$ ^6 C6 c: { my-row ;; the row of the intersection counting from the upper left corner of the- H' @8 {% u' d2 d
;; world. -1 for non-intersection patches.8 [, V2 w. k4 S3 ^0 Z# |# m% u# o x
my-column ;; the column of the intersection counting from the upper left corner of the
# A. h* ^9 D& ^- O. B5 A& g+ g ;; world. -1 for non-intersection patches. {1 W1 z& M1 w7 G m6 M6 ^
my-phase ;; the phase for the intersection. -1 for non-intersection patches.- O0 ~$ C# p% H$ J
auto? ;; whether or not this intersection will switch automatically.
2 r) M6 f8 v1 U$ J) _/ f ;; false for non-intersection patches.
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5 [5 l0 s1 Q0 |* q0 s;;;;;;;;;;;;;;;;;;;;;;
3 ?& v8 }; K+ ~$ E" I6 I- H. T: q;; Setup Procedures ;;
1 r9 l7 ^1 ?$ J;;;;;;;;;;;;;;;;;;;;;;/ H# t% _% C' M3 i5 E2 [3 g
2 \* D& \+ Y% N7 D! g# s;; Initialize the display by giving the global and patch variables initial values.
1 S2 z4 X# d, Y8 [ V0 t. \;; Create num-cars of turtles if there are enough road patches for one turtle to1 v8 N8 @/ _1 Y- n% N/ x" m
;; be created per road patch. Set up the plots.
P/ z; H: r7 w" Wto setup
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C V, j. r5 ~ setup-globals4 S, ]$ x( D) I( _
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;; First we ask the patches to draw themselves and set up a few variables* h! P1 U; _( V' g7 _. z) L/ p2 x
setup-patches* X/ j( u1 `2 w4 W9 p7 ~" J- ]
make-current one-of intersections
- |) O+ o% p E1 M7 u label-current/ p; H$ J: E" V) \3 k& {& S3 X
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set-default-shape turtles "car"
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. @; x/ u9 b9 {, `* X if (num-cars > count roads)
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( W' f7 M0 z8 H2 ~ user-message (word "There are too many cars for the amount of "
5 L1 R9 N# d) H0 Q0 q2 Y, I2 G X "road. Either increase the amount of roads "% q$ D! V o. l6 |+ s4 o
"by increasing the GRID-SIZE-X or "! H7 z9 Z3 E$ u0 I
"GRID-SIZE-Y sliders, or decrease the "
3 [$ z) p7 Z' Y; F& G" s "number of cars by lowering the NUMBER slider.\n"6 O( _% Q3 D! n0 @+ H. d
"The setup has stopped."). {/ n# ]( S5 K7 `/ b
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color8 \: q8 |4 @6 m |
crt num-cars J7 m# a( g" l% j2 G+ f
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5 `( K7 o, T/ x setup-cars7 F, x) s) X! Q6 n) W5 C
set-car-color- R5 `8 o' H; G" Q+ r9 i
record-data
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, F/ D1 h/ e; N+ M) h ;; give the turtles an initial speed# V& L; }8 L, v2 N: d
ask turtles [ set-car-speed ]
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* d& e! d* [$ r6 f% G( h; N reset-ticks
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;; Initialize the global variables to appropriate values
# m' {5 w/ L! Bto setup-globals
# |9 o: C- S+ U* Q set current-light nobody ;; just for now, since there are no lights yet( v- ^' i1 F4 }$ t
set phase 0
1 d/ O9 u9 n; T2 B7 B set num-cars-stopped 0
* N0 {; m' l" z- | set grid-x-inc world-width / grid-size-x; y1 E5 N" v3 L' b, l0 a
set grid-y-inc world-height / grid-size-y! S3 m' C4 a) [/ T2 R
* K: T+ b* }9 m ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
* z- }% O- Q/ M9 n: C. F7 ` set acceleration 0.0995 {1 n" M+ U8 f7 ^
end) X8 I+ m5 D& w# W9 ^- A. A
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 `; `/ Y- b9 R;; and initialize the traffic lights to one setting
5 s$ m, o8 i/ A+ Q/ H/ a* G1 @to setup-patches: N2 W7 f% h7 \% J, A% r1 {
;; initialize the patch-owned variables and color the patches to a base-color! \8 k( Q: f5 b' U: E7 B
ask patches
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( |8 H$ x( b5 U2 N2 t set intersection? false
% x" z( S- m% S \& D' g( L) Z set auto? false
* s u: x6 L g! F( T; L* {$ m0 u- \ set green-light-up? true
) g% q3 Y) S) q! ]! A" J9 P: P set my-row -1
3 c! @/ X K# {0 j$ j0 T, y" z+ z" h& k1 { set my-column -1# f: _8 w. [" O: n& ~6 x( z
set my-phase -1
+ {. h6 H0 I- y/ y4 l6 s6 R! f set pcolor brown + 3
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# m+ @0 h# N& o9 N4 W ;; initialize the global variables that hold patch agentsets l* c1 M, Q, ~3 [& I
set roads patches with7 Q% K& C; Z& K' c, i$ ~$ o5 M
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) P2 h u8 G- t$ x# W. k1 Y% q$ { (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ R) u' y9 ]" Y* ^8 ^. T f set intersections roads with6 L$ j- r6 N; j7 g% J% E
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ l7 _& v0 i1 C7 _$ S4 W# t, b+ h (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 \/ t: H' M" \' f w9 U1 ]
3 O/ n; G6 s! j' n$ {) I ask roads [ set pcolor white ]
4 N$ Y: S8 j- J/ L% } setup-intersections. n) }0 ^/ p' [+ H5 }$ _+ O
end8 [) q$ _' D; A, d4 X
其中定义道路的句子,如下所示,是什么意思啊?
6 w1 T$ m4 p; q ?" M/ P set roads patches with; m; S- B+ q, O$ W
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ L& |, z; {4 `( m (floor((pycor + max-pycor) mod grid-y-inc) = 0)], d7 K% {9 e2 n* Y7 N, j
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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