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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。
$ K2 ^* Q& v) [; w' ^& fnetlogo自带的social science--traffic grid这一例子当中,
1 S) u |9 ^5 v+ }2 V8 f: E# iglobals! S8 n$ k6 ^! {2 @' T, u4 L# `7 ^# J
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- C$ k0 y. Y" K! v$ j( L grid-x-inc ;; the amount of patches in between two roads in the x direction
- ?% |5 T! B% b* @% q5 f9 ~ grid-y-inc ;; the amount of patches in between two roads in the y direction
) Q: A- h! i: T+ a) S9 l0 } acceleration ;; the constant that controls how much a car speeds up or slows down by if
; w5 L+ Q2 q$ U9 R7 [+ V ;; it is to accelerate or decelerate7 I$ Z' p6 g/ M* L* u4 T" K
phase ;; keeps track of the phase3 L( Y, g7 C+ e1 X7 m' U4 Q) X+ n! x2 \. E
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure- A5 ^; E2 E4 C; e3 _
current-light ;; the currently selected light
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1 P/ [2 |3 D M) p/ u1 y2 X ;; patch agentsets+ N; n- G; @# U A0 s7 }
intersections ;; agentset containing the patches that are intersections
1 B: X. D! ?! [5 k+ s; r! s7 O* ^; i roads ;; agentset containing the patches that are roads
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turtles-own
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speed ;; the speed of the turtle
, i$ C9 ]% V3 J6 F; b up-car? ;; true if the turtle moves downwards and false if it moves to the right
5 ^' S- ]$ y% W2 O4 @. [ wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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1 [. h# p3 S! |% u8 k% S intersection? ;; true if the patch is at the intersection of two roads
# _& R/ u- \: K; [4 q1 J/ ^3 s green-light-up? ;; true if the green light is above the intersection. otherwise, false.
2 |; h G, \# J I! g$ d ;; false for a non-intersection patches.( X& Z2 P! }, H3 _: E& W
my-row ;; the row of the intersection counting from the upper left corner of the _, r* d- d: Y4 ]% }- y) q2 b( S
;; world. -1 for non-intersection patches.
; d: G# F$ A: G( I3 O my-column ;; the column of the intersection counting from the upper left corner of the
9 O$ O2 A3 s/ O$ }; ^( c0 c% J ;; world. -1 for non-intersection patches./ [+ d1 f) J& J- R$ F7 ~2 I
my-phase ;; the phase for the intersection. -1 for non-intersection patches.6 g& n& J3 r6 Q% h/ f
auto? ;; whether or not this intersection will switch automatically.- _+ B9 y7 I$ n& C3 ~
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;8 M* U1 h; U; y7 f/ O7 s& E S
;; Setup Procedures ;;
$ R- u' k. p' K9 |$ D;;;;;;;;;;;;;;;;;;;;;;
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$ Z3 [$ a& p; `5 o3 @;; Initialize the display by giving the global and patch variables initial values.
5 G" x" D O) z7 ]: ?% ?" \;; Create num-cars of turtles if there are enough road patches for one turtle to& w6 t; G' s. H
;; be created per road patch. Set up the plots./ Z+ L5 V* Q' B+ [
to setup
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setup-globals
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+ L" w5 Q) _8 }% r% }% b ;; First we ask the patches to draw themselves and set up a few variables
: U) x/ v5 V! M" |3 e% G; ` setup-patches6 s1 [3 b4 E8 H* ^) ?) z7 q: D H' c7 G
make-current one-of intersections
9 `9 t; M& c0 \1 {+ Y0 o label-current: Y* w9 v7 ?9 N9 M3 ^* L! c
# ], q: o/ r) {+ E; Y. D+ T; b. |: g set-default-shape turtles "car"
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( j0 n; f1 Y. \$ C: i; | if (num-cars > count roads)4 o" s! [; J3 Y# b4 f, K
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4 `9 }& z- T' V" D user-message (word "There are too many cars for the amount of "1 ?: y& e* u" c! n
"road. Either increase the amount of roads "
" v1 A* r6 E4 }- {3 F* n: [$ z "by increasing the GRID-SIZE-X or "7 i4 O. B* n$ ]/ y U' C6 k
"GRID-SIZE-Y sliders, or decrease the "
. E9 d" n% q% ]) g "number of cars by lowering the NUMBER slider.\n"$ k6 ?% a+ r& b8 ^' Q) q" u; V/ S# W
"The setup has stopped.")
/ U, u+ Q. g. F7 f6 m" F% q stop$ R5 | V9 |" L; }8 S- o" k
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" X, K! c' U4 l5 z crt num-cars# ^% M4 u4 O( }& v! r
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setup-cars7 I" q+ g/ n# H! Y+ u7 u
set-car-color
! N; ]7 o( E8 F5 v- t record-data
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( @6 H/ p; G& [7 p$ h ;; give the turtles an initial speed1 U+ S5 x/ \3 h$ A7 u7 K" f
ask turtles [ set-car-speed ]: R, T: t) ]9 b1 U5 O7 Q {& ~1 [) U
- O- U9 l' r5 n! P4 H reset-ticks" ~* g! t% r; b9 w( U4 I- G% u" o& l
end
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) k: S0 z9 ^! e6 P- q/ g;; Initialize the global variables to appropriate values
# ? u+ h7 V7 tto setup-globals
. ]& |# Q7 I& C) [* K4 T set current-light nobody ;; just for now, since there are no lights yet
% C3 L" Z0 |& P" j+ I set phase 0
) m- b9 i" ~9 o7 F& B+ s0 C+ L set num-cars-stopped 0
R+ [! G+ J8 O set grid-x-inc world-width / grid-size-x
! G% O, R6 l5 _& \5 W } set grid-y-inc world-height / grid-size-y) v4 ]& u O- g+ @" m8 p
/ T& p/ R) N, K4 x' c/ J ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
: L0 l2 s b6 x9 d* `8 S' b set acceleration 0.099
5 ~& H: X8 T! N4 X4 Jend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,( l" ~9 T) l, W1 l, G
;; and initialize the traffic lights to one setting
) Z0 i* H' t1 d" O2 D6 s- C5 oto setup-patches9 v% D% |; G: C5 R- G/ A" v
;; initialize the patch-owned variables and color the patches to a base-color
+ q% d9 \4 I4 _6 }7 D ask patches
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set intersection? false7 @- W9 k9 H0 u4 ?
set auto? false. T k0 H" b. S7 |( Y
set green-light-up? true
0 L2 T# C) w, g6 K set my-row -1
. y& |, x7 s) {' j s0 x set my-column -1% o8 a. E9 \% a( w
set my-phase -1- o, V+ r6 D/ n1 s+ b
set pcolor brown + 3; ~8 b. I4 @: { u8 f# L7 l7 I1 B
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8 N3 ^. x6 K D' x ;; initialize the global variables that hold patch agentsets
# @% G- }$ V/ l0 A set roads patches with5 f$ m7 a* a$ C% S7 Y4 T$ A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. l% X+ F9 q8 Q0 G (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
1 {/ p& p+ ~: I$ u6 N% t set intersections roads with
3 ?; m m+ b7 C: x9 V7 A5 Q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
9 d! _- Z2 l& P6 C) s- Q! ]9 ?! } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ i7 x- Y* ?/ O1 R
* O" e/ l, R5 Z: T- N- F9 O ask roads [ set pcolor white ]2 M$ c& E: e* l G; `, n
setup-intersections3 u7 o! F: O+ @2 D
end
! D. `' k/ q; A: J其中定义道路的句子,如下所示,是什么意思啊?3 w5 X5 \% P6 L/ K) @
set roads patches with; u ]& V8 N% |9 @/ ^6 \
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or9 {! ~, R: W; u5 k8 S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 |7 ^; H# `! L* @. U6 h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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