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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。
: C \( H( j# V1 O6 v0 tnetlogo自带的social science--traffic grid这一例子当中," R% b. v. G( ^3 u4 F' L3 E
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction9 s$ w/ g5 ~1 n
grid-y-inc ;; the amount of patches in between two roads in the y direction7 @' e- @! ^* S2 X$ c- P: |# a0 B
acceleration ;; the constant that controls how much a car speeds up or slows down by if
% B* q1 b) W% ? ;; it is to accelerate or decelerate! I- O& x' a$ V5 J5 F& C
phase ;; keeps track of the phase# j% X$ ?0 s2 d3 r- S
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure9 `9 b, N( Q& e# d. f6 C N9 v G6 w
current-light ;; the currently selected light* X6 v# ^& u8 r" B8 P' ~& T
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;; patch agentsets; S% {3 V& y6 a. b& j3 B8 E
intersections ;; agentset containing the patches that are intersections& N' G _0 y% s* B
roads ;; agentset containing the patches that are roads
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/ H0 R' L1 `, p) vturtles-own% G/ J2 V* K; ^8 a5 H1 k
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% t o5 T1 A7 H& J, F/ Q speed ;; the speed of the turtle* F6 P5 E3 x. {) t6 N4 ^4 B
up-car? ;; true if the turtle moves downwards and false if it moves to the right
# d/ c/ c; a$ X, X9 G2 g | wait-time ;; the amount of time since the last time a turtle has moved# E& d) z) Q ?0 B7 L
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patches-own
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U! b$ T& N( W, L8 D0 W( [1 a- l intersection? ;; true if the patch is at the intersection of two roads
& N! Z# ~( L4 V0 ~( C green-light-up? ;; true if the green light is above the intersection. otherwise, false.! i& w# k% C1 L" d( ]% ~7 W
;; false for a non-intersection patches.; @( A6 ?- {( _
my-row ;; the row of the intersection counting from the upper left corner of the" z1 S; O* M0 S
;; world. -1 for non-intersection patches.
9 X2 [& }5 Z: | my-column ;; the column of the intersection counting from the upper left corner of the; D& e; T9 J* S# K# K( f1 Z/ s- o
;; world. -1 for non-intersection patches.
; P3 [2 K! o8 V1 z0 { my-phase ;; the phase for the intersection. -1 for non-intersection patches.9 G5 t" q4 ?" n. `7 G8 T0 D( i- a
auto? ;; whether or not this intersection will switch automatically.4 r E; Q. D& ^) T! _3 G
;; false for non-intersection patches.
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0 M! n4 f' N) K;;;;;;;;;;;;;;;;;;;;;;
3 C2 k% X% o7 v5 I& B& I. `;; Setup Procedures ;;
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5 p) ?0 T8 D/ z$ U. o' v6 T$ ]7 ~;; Initialize the display by giving the global and patch variables initial values.
9 H3 D" C7 o) k5 \0 L;; Create num-cars of turtles if there are enough road patches for one turtle to/ n- B6 o. M5 {5 K
;; be created per road patch. Set up the plots.
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ca
- D6 m* S4 ?+ j# S) @( W setup-globals) E7 Q( L* C1 `* o8 ]# b& o+ i
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;; First we ask the patches to draw themselves and set up a few variables
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make-current one-of intersections, J( W2 Z7 ~0 H" m2 e. ?' s
label-current7 E7 M% K! I* `( q
' N' w3 d0 }8 p% g( ?6 f7 V' G set-default-shape turtles "car"' [8 s! M, K5 o8 P6 Z/ r# y& K% z
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if (num-cars > count roads)
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/ h. e5 `3 d. w( `+ r" L/ [& ? user-message (word "There are too many cars for the amount of "
( o+ f. I2 h I! k9 n: s1 z! @ "road. Either increase the amount of roads "/ c4 ~+ ^8 L+ g. g r% _+ D
"by increasing the GRID-SIZE-X or "
0 ?9 s6 k* l' a1 ?; x- d/ X "GRID-SIZE-Y sliders, or decrease the "" x1 r6 d# ^3 u' }- ?
"number of cars by lowering the NUMBER slider.\n"0 n# n; w0 ?' k
"The setup has stopped.")
- D! }+ A# B& A& T) X" p stop
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+ R: [! m" a1 Z5 \' S h1 A ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" a( a1 @( c( S* [" r crt num-cars
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setup-cars U8 i1 q. {& j0 U k+ ^
set-car-color
$ Q% H4 e j. o' s record-data
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;; give the turtles an initial speed
+ X( N/ f( M8 ?& T5 t( p ask turtles [ set-car-speed ]
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% ?" p9 s3 V" l reset-ticks
. i& \0 C% D3 W4 gend
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;; Initialize the global variables to appropriate values" q) K. P3 J$ q; ~& A# b O, c
to setup-globals* t3 E' W) Y1 W2 m) S7 q
set current-light nobody ;; just for now, since there are no lights yet/ K" O6 S# R! v c9 ^+ k2 W
set phase 0( P* b( I3 W% |, o
set num-cars-stopped 0
l, T) G: i5 d" L0 F6 c6 K set grid-x-inc world-width / grid-size-x1 C: L" l$ {' q& a2 T6 ?
set grid-y-inc world-height / grid-size-y6 V2 _. p; s+ x: Y3 b2 ]
8 {! y3 m" `1 T# E4 S% x4 Y ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary$ c; j# G) E" c/ p
set acceleration 0.099* |+ s% M% g) X4 Z( k3 K' I
end
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9 y0 J+ `, g0 N5 \2 G7 x1 W;; Make the patches have appropriate colors, set up the roads and intersections agentsets,- O2 v' F ^9 I, ^4 S. }+ N+ n: V
;; and initialize the traffic lights to one setting$ _+ [1 h4 I7 b
to setup-patches9 T* x8 n2 x* _+ ^5 @& U9 i+ ^
;; initialize the patch-owned variables and color the patches to a base-color! N& g- T2 W2 s5 P' t
ask patches9 s8 k! x- ]0 a# z7 l. A
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c9 P" y1 M: |. e, d set intersection? false
+ W7 X0 K; i" f# a% x3 t3 S$ O9 r$ b8 G set auto? false6 Y& G, s: E y0 Z* T
set green-light-up? true# s9 R" P& Q. \
set my-row -1
5 j6 ]% X. E4 V# q/ t& ]! m set my-column -1
* M3 E# v5 k& x0 A# ^3 M set my-phase -17 _ p& }& D9 N9 Z9 i
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
9 u5 l6 r* ~% m set roads patches with
# y+ @9 n. F3 J! |7 q6 t# I( q [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- E- r5 _7 X" f* r+ p
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
4 L) k" s r- R w; x/ b (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 J# C) I [# V. Z6 [0 m
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ask roads [ set pcolor white ]) C) \' ~6 f% }" B* T7 k, A
setup-intersections% \" t n- t- z" {( p3 D: ~: Z
end. G1 n9 L7 ]6 u0 a8 |- }8 l
其中定义道路的句子,如下所示,是什么意思啊?' L6 d& i* p1 r% W/ [4 f, U) I
set roads patches with5 }, B3 _, y. U; ~: Q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 T0 x. |. M- ^2 @; K8 q2 h: `
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: v/ b, n% H0 B) X G9 x f0 R7 H" x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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