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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。
' M! W' ^9 J( G( H) z' Fnetlogo自带的social science--traffic grid这一例子当中,
. K3 T3 [8 L8 `7 k1 sglobals
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" x2 s; A, X% [ F grid-x-inc ;; the amount of patches in between two roads in the x direction
3 x6 h* ^% j- s0 L6 _: n grid-y-inc ;; the amount of patches in between two roads in the y direction7 b% g% A* f7 Q& k& Z1 r/ a
acceleration ;; the constant that controls how much a car speeds up or slows down by if b+ ]+ R" {* Q1 \7 X5 Z* ]& [4 y
;; it is to accelerate or decelerate2 U: T1 b N8 d9 D3 \
phase ;; keeps track of the phase
; b5 N" u3 p% ?8 @1 B( i0 o, \ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure& o) D) k1 b$ K5 K9 K, b0 V; m3 l
current-light ;; the currently selected light. O7 q+ C. g" `8 }& G3 j
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;; patch agentsets! W+ z6 G6 b; U8 s8 k0 E: b
intersections ;; agentset containing the patches that are intersections. l( ]) ]- d! D% k: J( b+ O9 u
roads ;; agentset containing the patches that are roads
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! U' a3 W8 I% b3 Y+ Mturtles-own
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% A. b$ e* w2 Y: b speed ;; the speed of the turtle
P- J8 q; s: d( a1 ^( x0 n up-car? ;; true if the turtle moves downwards and false if it moves to the right, t; d! W- X: I& U v. B9 h6 M
wait-time ;; the amount of time since the last time a turtle has moved
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8 _ c2 }# K+ w9 q4 C2 m+ vpatches-own
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4 E* c- O3 d9 \& j5 L intersection? ;; true if the patch is at the intersection of two roads
4 {* H4 x- Q4 T1 f( L green-light-up? ;; true if the green light is above the intersection. otherwise, false.
$ l2 y C- o* f$ H V8 B ;; false for a non-intersection patches.
0 n! ~0 E7 W/ _2 a1 X3 s, P my-row ;; the row of the intersection counting from the upper left corner of the
* e- q5 e( A X% f% G" Y ;; world. -1 for non-intersection patches.
( a8 [9 _' h& X4 u my-column ;; the column of the intersection counting from the upper left corner of the3 `/ c; |* B3 z* z, u
;; world. -1 for non-intersection patches.3 D9 Q" B/ C4 t5 t1 p
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
( c; c/ ^3 h+ _0 I6 E auto? ;; whether or not this intersection will switch automatically.
# |* H; `. `- [7 ]; [0 R. S ;; false for non-intersection patches.
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/ E; x8 I1 J, D. E$ S/ ^;;;;;;;;;;;;;;;;;;;;;;
; u: {, @, e# |5 g+ c3 Z;; Setup Procedures ;;
1 x6 [8 Z+ n0 c+ m. ]- b! g;;;;;;;;;;;;;;;;;;;;;;1 v; ^+ n0 ~1 {% ]5 l F: _
$ {3 D# A- c0 P# K% v3 ?/ h4 P;; Initialize the display by giving the global and patch variables initial values.2 J6 j1 Z3 C9 M- e0 V) |
;; Create num-cars of turtles if there are enough road patches for one turtle to5 B6 e; ]) [ B
;; be created per road patch. Set up the plots.$ _9 n2 w. y3 E; `
to setup' p, O: E( G6 X3 K
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setup-globals/ j# V) K6 M6 X* D5 `
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;; First we ask the patches to draw themselves and set up a few variables8 {* R. n% y$ Y+ _, j
setup-patches. P" l1 V& w) z" r1 `
make-current one-of intersections
! [; G c7 H# ^+ \ label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)' t. U- ~/ k* T8 ^" F8 ?
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user-message (word "There are too many cars for the amount of "
) a% W, g/ T+ H' _ "road. Either increase the amount of roads "
9 V% W2 N% W! X! x2 M% e "by increasing the GRID-SIZE-X or "2 h: c8 w2 S: m1 g4 G
"GRID-SIZE-Y sliders, or decrease the "
2 }" [4 f% \& U7 M9 o "number of cars by lowering the NUMBER slider.\n"
$ l! @2 C/ Z* K1 G "The setup has stopped.")% ^" E6 s5 L7 F5 A4 t& R$ C
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
7 c9 |# z7 x# d crt num-cars
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setup-cars. [* \! N7 c! _% i; w0 {, b) ?
set-car-color& D1 `0 e" O( b) M" c& d4 E* p
record-data
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' s2 L. R+ i: ? ;; give the turtles an initial speed
7 c' C% s \6 j& Z* {* S ask turtles [ set-car-speed ]4 i% W) k9 ~% c( i5 v- X5 N
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reset-ticks+ J% f7 T5 W3 Y
end. ?8 B4 v0 p) z+ ^
# d& |$ G- ], t: g' Y. K;; Initialize the global variables to appropriate values
. N$ o. j0 t4 n2 J: ?to setup-globals, N4 R) A; W4 V, X0 W7 I
set current-light nobody ;; just for now, since there are no lights yet
# W7 S9 r$ I( L set phase 0
& X( I6 P/ I( O3 N set num-cars-stopped 0
- A0 o, O4 E) Z% T+ o5 P! L) z, ^ set grid-x-inc world-width / grid-size-x( p7 ^. Q0 R; H
set grid-y-inc world-height / grid-size-y9 N6 l7 q% x0 a$ ~, t* J$ U
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary% k: `- Z& M' f4 ?
set acceleration 0.099" y% l4 I4 s" T ?
end# h0 w/ y [( l5 _& ]
: {' o6 D- i3 G( ]# S8 A% R R, ]! T;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
4 P, v8 D8 C/ ^' W* ^+ ^;; and initialize the traffic lights to one setting
$ C5 H+ i8 b9 }: e# O) bto setup-patches
. t! }( \: ]2 A: J" ] O) L ;; initialize the patch-owned variables and color the patches to a base-color
4 T% m6 \ w3 {* b3 E ask patches: O! |' o' A) X. x; B# n% y4 D
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set intersection? false8 h& f4 r. }( n3 r1 R
set auto? false. r5 l% O% V/ [, `# g9 |% N
set green-light-up? true
& b2 @. @* B$ R& i$ ~1 } set my-row -1
5 Q* o& o% P+ g3 T7 h: A set my-column -1
K& M y& E( ^ set my-phase -1* D$ z2 d. R- R
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets1 q4 u6 v0 ]6 e
set roads patches with/ n$ K% f3 Z! h4 }
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 Z) r. z' O5 a3 \
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ x2 S4 t; c$ {& {/ d
set intersections roads with
4 m8 ]. [2 ~# h8 d/ B$ O$ M [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and0 T9 h4 F: D% W' K
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# `+ n, r4 ]* f8 E. q2 o; y. `. K# Q
& r$ d* F$ z' ^* R( b" w- { ask roads [ set pcolor white ]
# `4 s, y& Y* _$ K* w' e- U0 E% S 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?
. l% P. V1 y, R" K$ H& O$ c0 S2 g set roads patches with
L. Q# q7 C. `: P7 S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& H& C% p+ R# [9 y (floor((pycor + max-pycor) mod grid-y-inc) = 0)]9 `& s7 f t7 g: C% _7 [
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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