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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。
" Q: Y5 X% Q8 Z, v& Jnetlogo自带的social science--traffic grid这一例子当中,7 W" `# g4 a- j- ? U$ ~2 b( t
globals" c' \: {& t. r
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grid-x-inc ;; the amount of patches in between two roads in the x direction+ W. r* m8 n" O! Q
grid-y-inc ;; the amount of patches in between two roads in the y direction
" w/ M0 w5 G0 m2 I' x& w acceleration ;; the constant that controls how much a car speeds up or slows down by if' L/ P- P |& I& x: `" S. @4 v
;; it is to accelerate or decelerate
8 i8 \ \# x+ E4 ~ phase ;; keeps track of the phase5 o5 z, v v2 t& t) L
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure' y1 M9 \ v1 x( f; _0 s
current-light ;; the currently selected light$ J- [$ g2 D3 s
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;; patch agentsets
: C0 ~ J% Z- W; {! {4 t a9 e intersections ;; agentset containing the patches that are intersections
% [. Q$ v1 ]- P+ G A roads ;; agentset containing the patches that are roads- l; G/ N+ p/ u t0 N* v
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turtles-own
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speed ;; the speed of the turtle
* Z4 [+ T0 c# ^2 F2 t- \/ w up-car? ;; true if the turtle moves downwards and false if it moves to the right! F5 m2 i) B" s k/ X
wait-time ;; the amount of time since the last time a turtle has moved1 A' [7 x1 l; Q9 q/ A
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads# Y: v/ D* E& C( Y# {
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
) ?$ ]2 @/ N' d% ^0 z ;; false for a non-intersection patches.
1 H% P: n! z7 G. Y6 K; e my-row ;; the row of the intersection counting from the upper left corner of the
9 H: c. T" u9 [2 S( w ;; world. -1 for non-intersection patches.. {" o9 `$ R( ^, a* u
my-column ;; the column of the intersection counting from the upper left corner of the: U, @. W6 ]$ ^, T3 H
;; world. -1 for non-intersection patches.2 \2 m" d6 ^6 m9 R1 U
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; V0 e6 ]: p* Y auto? ;; whether or not this intersection will switch automatically.# d0 p# z. u4 T* I( W7 @
;; false for non-intersection patches.8 B& [9 U3 F! O7 I$ k! E
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;;;;;;;;;;;;;;;;;;;;;;
! N0 q: s+ ^! b' Q8 J0 g# o;; Setup Procedures ;;+ Y, [$ V7 C% K
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
. K2 P/ \) W2 B;; Create num-cars of turtles if there are enough road patches for one turtle to4 E6 x3 k( O# {* h: n* y" R; ^
;; be created per road patch. Set up the plots.7 |; i' d: h6 I2 y
to setup
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setup-globals
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4 G9 v% s5 H; v$ N: K8 Y ;; First we ask the patches to draw themselves and set up a few variables
6 u9 k# c* c7 u9 Y$ m2 Q8 a8 f setup-patches
* _0 |3 r2 `2 x; q make-current one-of intersections B8 z# y F" }5 i8 e
label-current
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set-default-shape turtles "car"
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$ @6 X2 D" M: D1 V$ F if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "+ @9 N/ |( P/ C5 G: N' z
"road. Either increase the amount of roads "
9 B) X j& w% ~2 y8 {, [# j" H2 r "by increasing the GRID-SIZE-X or "! l j$ j2 H4 F( ?6 P
"GRID-SIZE-Y sliders, or decrease the ") |/ T# ]4 Y$ k6 X
"number of cars by lowering the NUMBER slider.\n": h f& B6 t. s
"The setup has stopped.")
" G3 c3 x% N! M+ [+ i2 `) t5 _. u stop' O( @9 v0 m1 D
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+ O# {" l6 N1 e, g5 l+ L ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color. W: l6 {& d3 [7 d, c$ N' _
crt num-cars
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setup-cars
! M% C9 k6 @8 j; w set-car-color9 j) q6 A3 N2 E ?" Y( n
record-data9 v8 c8 q4 O) O* ? ~# x& p
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;; give the turtles an initial speed3 @; b z8 p [# s
ask turtles [ set-car-speed ]
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reset-ticks% h, q) Q5 h9 J% B0 }% X% y, M
end5 O2 M9 d- I( @: h) W4 r+ w
& h) V; c* L; {6 S$ n;; Initialize the global variables to appropriate values
+ O% D( d( s6 I E. F+ Tto setup-globals
) p. l7 _& K2 l0 H4 L" ^% Z set current-light nobody ;; just for now, since there are no lights yet
7 k. s8 ~7 A4 q5 f% D/ O set phase 0
; u% y3 ~8 o# G4 z$ j5 o set num-cars-stopped 0
4 j( o t1 p0 F+ g set grid-x-inc world-width / grid-size-x/ U) f: \4 b/ ~$ ^2 f
set grid-y-inc world-height / grid-size-y0 W2 Q1 x: O+ e! h. V
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary/ `, j* J# F/ {4 L5 A _/ D0 A2 \% [
set acceleration 0.099" q1 ]( m; K9 b8 ?
end
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- ^! A6 T9 b6 F% O+ V: b. N. ^2 Q;; Make the patches have appropriate colors, set up the roads and intersections agentsets,# t% r# m% S: [. c) O7 U1 w
;; and initialize the traffic lights to one setting- [' K( [7 K9 ^, F1 M6 ~3 v
to setup-patches
) ?7 y2 Q% N% j% ` ;; initialize the patch-owned variables and color the patches to a base-color
& u- Y4 t9 T6 q ask patches
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2 J/ l' _# m4 d. V' ~' X( A* t set intersection? false
+ u1 x+ B; T7 P8 G set auto? false
8 S Y$ ^: D$ X5 w set green-light-up? true
1 G; {) |- w* }0 n* E% k; `" P set my-row -1
- q$ |+ u) O# ^( l7 a set my-column -1
# G% {- ~: i0 R" f S set my-phase -1
' \$ w `8 `7 Z K4 b! Y set pcolor brown + 3
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8 c3 ^' a+ e' K' E3 i; I [1 f9 X ;; initialize the global variables that hold patch agentsets$ d; S. F# f" f8 b- l1 |7 U } G
set roads patches with
: K" S4 m1 {/ X+ h7 p: J: K [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) h& z& |9 E* \
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ ?7 @" J* q4 e3 c1 A. \ set intersections roads with
; Y7 Y) d; v8 s+ z* X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
; t9 U4 [( }' U: U( e/ h/ j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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( _) r, n# w. o# c ask roads [ set pcolor white ]
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end
. T% ~8 A* p3 H/ I其中定义道路的句子,如下所示,是什么意思啊?# q: ?6 n$ U( O/ g8 \
set roads patches with
+ U B. K9 ^( }) ^ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' _/ a- M# c( y% |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- s, [, |5 A/ c. w0 G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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