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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。
, V- T2 y* R8 v& J6 gnetlogo自带的social science--traffic grid这一例子当中,, s4 Y2 T/ i2 t5 \9 J
globals5 J g; [$ a7 V/ ^, c2 m
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grid-x-inc ;; the amount of patches in between two roads in the x direction5 ]7 M4 v }& P; Z' G" `
grid-y-inc ;; the amount of patches in between two roads in the y direction
' u. K* y0 G/ [9 ^ acceleration ;; the constant that controls how much a car speeds up or slows down by if1 E/ k! A8 A) v, d* ^! Q
;; it is to accelerate or decelerate
9 b' _% `: r3 ~- d* c& N phase ;; keeps track of the phase
1 ]+ w, e1 I7 I) Y+ U num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
$ H* w2 Y) {9 G+ L current-light ;; the currently selected light
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+ }) B9 f# e. |/ C8 G+ @. K ;; patch agentsets
$ H, d0 I) r# V intersections ;; agentset containing the patches that are intersections8 Y* a0 M# c# M) K9 c
roads ;; agentset containing the patches that are roads& _! Y8 ~ r$ c6 i1 a! Q
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' s1 J% y* f8 r% N: Z7 iturtles-own# c! c; `$ y1 u. `
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. s- J1 e* u1 N speed ;; the speed of the turtle
) i4 L/ \3 \, ?7 e- n up-car? ;; true if the turtle moves downwards and false if it moves to the right9 i: t1 K. N2 M* ~& B# ~& V+ [2 i
wait-time ;; the amount of time since the last time a turtle has moved
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- ~' [' h1 U' k) n% s: Dpatches-own
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9 d5 ^4 c, X" J intersection? ;; true if the patch is at the intersection of two roads' F! V9 k2 J! |, ^+ P$ u) y
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
9 c8 O6 y* u6 Q( W ;; false for a non-intersection patches.
1 {9 a+ M" c) }, E$ i/ L2 j my-row ;; the row of the intersection counting from the upper left corner of the
% ?7 v: v( Q0 k6 m! V ;; world. -1 for non-intersection patches.
& @4 o1 k6 r/ U, h0 y my-column ;; the column of the intersection counting from the upper left corner of the! g- }0 e1 [: H# v; U9 `5 S* E
;; world. -1 for non-intersection patches.4 z+ H5 g, q8 l7 A4 y! x) j( E
my-phase ;; the phase for the intersection. -1 for non-intersection patches.8 w$ Y$ A7 [% s8 S6 j. z
auto? ;; whether or not this intersection will switch automatically.! k( m2 o, |4 H. i
;; false for non-intersection patches.5 X4 E! C8 C- G5 c& c5 S: J
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0 T- O9 k- ^$ ?/ {# F* D1 d* ];;;;;;;;;;;;;;;;;;;;;;
/ {7 P) A% i' m3 w;; Setup Procedures ;;' R5 R" F" x, o g4 u0 i1 c( p
;;;;;;;;;;;;;;;;;;;;;;
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1 z6 l, q% f& @% J;; Initialize the display by giving the global and patch variables initial values.
" e% e* f9 U8 R S0 j;; Create num-cars of turtles if there are enough road patches for one turtle to
2 U3 K2 v- n9 W+ ]. W, a; }7 L;; be created per road patch. Set up the plots.
3 r- [, m, T% ~) p; S- @8 Q/ H! Cto setup% {% v* j6 R( ]2 T0 S7 v$ H3 u
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setup-globals
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# f! {2 x/ ^$ m4 M# F ;; First we ask the patches to draw themselves and set up a few variables% V8 H( F0 X6 \/ F
setup-patches. a5 ^% n+ q$ U$ p' h5 x! o( y! X
make-current one-of intersections
; R. c5 S' N6 Z. I0 w7 @ label-current" N! b: \3 q+ a2 U5 i4 c s* z V
9 y- B% i* r% ]& |6 S6 O& R& k8 `! S+ f set-default-shape turtles "car"* y/ a4 \1 u. v8 x4 w% n
( D5 }2 J( j3 D8 h if (num-cars > count roads)
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( r& D4 A' s: h( B. b- g% R" L' p user-message (word "There are too many cars for the amount of "& `; }5 f+ Q5 n7 a& ^ F. z; Z
"road. Either increase the amount of roads "
5 T. a1 w: ^$ r( d& j "by increasing the GRID-SIZE-X or "- X0 n T3 U3 [, j+ q
"GRID-SIZE-Y sliders, or decrease the "8 |! D3 r& f; ~. j+ S/ Y( \
"number of cars by lowering the NUMBER slider.\n"
8 B! N/ U) Q( p "The setup has stopped.")
. o, w/ v; B u- w7 Y( _# J stop# o; d* G w9 \9 J7 m$ o3 ?& ~! S
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* o1 L; I4 n+ Q7 s, a/ q ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" u8 l3 B& z* K7 M crt num-cars; H: H- E5 P0 [5 e$ ~
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& n5 Q, h2 V d! p setup-cars
7 j+ B2 u- z1 L* P: B* [ set-car-color, `1 t3 d; E; C9 _: R
record-data
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$ ?1 Q+ M9 h7 L ;; give the turtles an initial speed0 Z0 t! ?, _; \
ask turtles [ set-car-speed ]/ ~. I( h8 H; g* L, @( i
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reset-ticks" |" m& z! K" x% F1 C
end
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/ V0 q3 }; r, U* ?4 \;; Initialize the global variables to appropriate values
7 ~9 Z' C9 N4 i9 K5 ^to setup-globals
$ O; D6 G2 a. L, K g set current-light nobody ;; just for now, since there are no lights yet5 N! I4 P( ~. _3 ?
set phase 05 ~4 n$ {8 A. G
set num-cars-stopped 04 V" d2 Y3 I6 X* N$ Y8 F& C
set grid-x-inc world-width / grid-size-x
; a4 q! m' ?2 J6 e% M+ v3 [$ V set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
! s7 V7 p" Z. R- _$ a4 ~8 B5 B3 [) m9 ` set acceleration 0.099
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" v' q9 F4 D5 Q3 B% A;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
3 q( K# q4 s8 r5 l! \0 V# ^;; and initialize the traffic lights to one setting
6 B3 ]9 q. ]& {6 _* v1 ~" ato setup-patches. n' i* I# @" |3 Q" |
;; initialize the patch-owned variables and color the patches to a base-color
; Y+ }% R" n& p2 q ask patches
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set intersection? false
: @. V9 c/ Y% w+ u5 |& k set auto? false
: y/ ^) {% w* g9 N& F- Y set green-light-up? true. |, F& z. ]5 W8 c i; {% n
set my-row -1
7 R% G! x2 g/ U' d set my-column -16 C( d! D7 p$ }
set my-phase -1! b# c1 r. K( s9 U M0 f; U
set pcolor brown + 31 x- K1 X0 O$ r! X1 }
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;; initialize the global variables that hold patch agentsets/ U/ U3 ^" V- u
set roads patches with) r8 N" u; O- i; I% v6 b
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) f, E% F) H5 H3 u8 u7 U (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# C8 ^# R- N+ e, a. U set intersections roads with
6 q1 Z- e( |& E2 {6 |7 l" D& ~( V' B# W [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and6 }+ }- _; x. ]/ I0 m; Z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]0 P4 W- y7 T. I! \9 F" h4 u( M
setup-intersections
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1 @$ L5 \ S- e0 Z }- |3 e* i其中定义道路的句子,如下所示,是什么意思啊?( N1 r8 l( `4 r- k1 W- B, o$ T
set roads patches with5 x2 _' R3 j" M" b
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, d5 \' K% n6 q3 j9 Z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
, j1 {/ e s" z# i; E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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