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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。
3 X1 i2 x8 D) N6 o$ v- Pnetlogo自带的social science--traffic grid这一例子当中,
! U! q$ A$ y. g# dglobals# [9 E+ Q ~& i* F- k/ O
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grid-x-inc ;; the amount of patches in between two roads in the x direction0 o5 c3 C# q. ?- h# a
grid-y-inc ;; the amount of patches in between two roads in the y direction" L' v% i/ k, Y/ M( A
acceleration ;; the constant that controls how much a car speeds up or slows down by if8 {5 t, o* @, A6 e' }( c+ i
;; it is to accelerate or decelerate( `$ y0 n2 E8 U' B) _( c
phase ;; keeps track of the phase8 A5 ?$ k# N) O. b7 G
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
/ H0 ]! P/ @8 d* c5 W0 x. V# Y/ L current-light ;; the currently selected light
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V: y2 l: `6 @- k W0 m6 [+ G7 c ;; patch agentsets+ R! D( V. K. }; X
intersections ;; agentset containing the patches that are intersections
/ u6 v0 ^, p0 h; i, q roads ;; agentset containing the patches that are roads
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turtles-own
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* B8 [+ G% O4 G; D2 P$ {- w speed ;; the speed of the turtle! e5 @ x$ B Y2 l0 P! ?
up-car? ;; true if the turtle moves downwards and false if it moves to the right
( u7 h- B# Q1 q, M' H, [" j wait-time ;; the amount of time since the last time a turtle has moved
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patches-own5 h0 @& S8 v& b) X0 b; V' P
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* t! P! ~: Q" Z+ w) m: [ intersection? ;; true if the patch is at the intersection of two roads
( k! @" p9 k5 [3 c green-light-up? ;; true if the green light is above the intersection. otherwise, false.
p0 O8 b3 X# F* T- z ;; false for a non-intersection patches.
1 j4 R3 l* ? L: l my-row ;; the row of the intersection counting from the upper left corner of the3 `1 D) x" ]+ Y7 @$ k
;; world. -1 for non-intersection patches.
+ O5 t2 k- |8 m$ e5 B: V* K my-column ;; the column of the intersection counting from the upper left corner of the* a/ ~, `6 S$ C% c
;; world. -1 for non-intersection patches.
! A: q3 {8 ^. x! g my-phase ;; the phase for the intersection. -1 for non-intersection patches.( a8 Z8 n% F$ N/ Y
auto? ;; whether or not this intersection will switch automatically. y8 R# L* T( o' a
;; false for non-intersection patches.$ v2 |8 ~( x% V1 s' k7 m
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;;;;;;;;;;;;;;;;;;;;;;; C& }% G% l# c: T
;; Setup Procedures ;;* N! B) [- f. e7 ~
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values." w0 P% B" l$ y- h: t* k
;; Create num-cars of turtles if there are enough road patches for one turtle to
+ Z& I5 s- L4 P4 R% T; d;; be created per road patch. Set up the plots.& I- s C% q6 L( b/ o" g
to setup- Q( n4 Q! {7 w' x* r4 N
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setup-globals
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! H' G- H* J, W' ^% ] ;; First we ask the patches to draw themselves and set up a few variables
w. U' o3 S/ f3 v setup-patches
( l6 _, ~, R2 { B make-current one-of intersections
7 c4 i; y1 ^ M# m- |; @* u! A label-current
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set-default-shape turtles "car"5 o2 q1 `/ j# s4 w0 I5 l- x& u
. O3 D! g5 R3 `# G if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
. @9 @7 `2 u, M, c& a% j3 H: \ X "road. Either increase the amount of roads "0 Z- x8 Q* j8 O
"by increasing the GRID-SIZE-X or "
, O0 L9 I( ^* q* \ "GRID-SIZE-Y sliders, or decrease the "
. t% L$ A4 Z& l% V$ M: @ "number of cars by lowering the NUMBER slider.\n"
. q+ f/ z+ O ^0 v "The setup has stopped.")
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color8 [4 M) v- {1 h! ~8 Q
crt num-cars
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( a ~- B4 A; n1 H0 t setup-cars
3 \' q/ ?, ?) q S8 u set-car-color
F7 i K% z4 ^# C record-data* K& ]! w' N; R" A
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; s9 ^7 `7 G: [! A" J ;; give the turtles an initial speed
b9 v, F- t3 V8 g# d0 d8 i2 L+ W ask turtles [ set-car-speed ]; b6 V1 L, V# |3 M! x: o' I+ m- U6 Q
, P" e$ a7 [, Q4 _( j9 l' V, z reset-ticks$ V; E8 h' W5 x5 y/ y& e
end
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;; Initialize the global variables to appropriate values
; d* L/ b- l0 r# X6 o. Dto setup-globals
' c+ a9 o N) G3 [: k9 i2 c set current-light nobody ;; just for now, since there are no lights yet
, Y, r9 r5 m; F* e, ?2 Z5 Q9 q) y set phase 0
Q+ g+ w t- t& Z' U; K5 t. N set num-cars-stopped 0/ D) a! c K; v K; @3 m
set grid-x-inc world-width / grid-size-x
/ S3 ~- P- f m. u8 f6 A& G3 [# U2 v set grid-y-inc world-height / grid-size-y4 g" [0 f# y+ F" t/ C
# Q7 F; |" Z' A( f, h2 `0 u; ? ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary6 V. N+ ]3 q8 c; {
set acceleration 0.099 P r" E: ~) A' F
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
( Q4 N5 S3 ~# @ M. B$ y; W;; and initialize the traffic lights to one setting% j- ~7 P# I0 L, D( z, h0 p
to setup-patches
?2 G. y Y. g9 l7 [ ;; initialize the patch-owned variables and color the patches to a base-color, w6 U$ k3 Q B0 p$ E
ask patches5 B( Q6 z( S9 a& d; ^- E6 m
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- m+ z( G! a0 i. U" q0 F set intersection? false
$ v3 Z# ^* Y* ]7 P/ d4 l set auto? false
+ P, o' g: s# k set green-light-up? true4 C+ c' ], T) h; j f2 A
set my-row -1# {+ n0 ?. F. S# ~( Z4 b. z. |
set my-column -16 ~8 R, N: l1 J/ V2 d) o2 o. N
set my-phase -1
p9 I0 T6 ] E+ G8 I% V" }, h9 Z set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets% S5 |: | p3 @% I" Q- s
set roads patches with, w3 w% b2 V' ^# q3 `
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' o1 U) Y8 o3 d R' ^/ s3 d6 M
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 W3 k4 c% V! |( f3 O7 S- ]
set intersections roads with
) g* K" J. S2 Q2 W* H: { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
, E. E$ z! Q% W( l. g" u (floor((pycor + max-pycor) mod grid-y-inc) = 0)]* N$ i0 c8 ?0 g6 B' m
+ b- B Q) y o8 a5 b6 `$ O6 d' r ask roads [ set pcolor white ]
7 P* ? \ ?6 t+ t, x5 Y setup-intersections
1 Q$ }4 V' t& h% \% |! }- qend
- g# V; o9 w: v; o8 [其中定义道路的句子,如下所示,是什么意思啊?+ H7 e. f- e m5 P; C
set roads patches with1 m1 [: r) ?3 Y! u; O
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 r* x0 C$ H" J/ M/ D: E* {
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
) \8 t+ C9 l; u0 h% ^ P+ P+ 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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