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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。; M4 w0 S7 c2 [7 O+ j
netlogo自带的social science--traffic grid这一例子当中,$ D4 ]' Q5 x+ g# Y0 |9 V4 h
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction% m" t: N# |4 i' Y( J
grid-y-inc ;; the amount of patches in between two roads in the y direction
3 B, J+ H1 m0 ?! x7 ^* @/ n' R acceleration ;; the constant that controls how much a car speeds up or slows down by if* I$ l$ ]+ n" c' t# o7 ^
;; it is to accelerate or decelerate; v/ u. W6 T* m% n" f& r" y
phase ;; keeps track of the phase
6 x( u0 H) [" o- V num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure; Q0 Q- M2 c3 h* p7 Z, _
current-light ;; the currently selected light
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/ @3 I1 U, { s) d. Z4 n% H, [( t ;; patch agentsets
. J: r# V2 J) x3 V4 } intersections ;; agentset containing the patches that are intersections( r- \' V: x4 H T" g
roads ;; agentset containing the patches that are roads
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& X& S: E+ g& z% n- i# f) N8 q8 dturtles-own
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speed ;; the speed of the turtle. b% o1 z( u4 j
up-car? ;; true if the turtle moves downwards and false if it moves to the right
0 Z- Z" j$ q# D9 a wait-time ;; the amount of time since the last time a turtle has moved
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patches-own& w2 [7 b& J: {& V+ [ l2 G
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: [; [# u$ N( y" W4 I) b5 B! r4 v6 ] intersection? ;; true if the patch is at the intersection of two roads
5 r# R( c; q0 n' I w& f green-light-up? ;; true if the green light is above the intersection. otherwise, false.
8 g2 N8 c0 `7 s& @4 a ;; false for a non-intersection patches.4 ?/ c- H! t, n& B2 G4 m) P
my-row ;; the row of the intersection counting from the upper left corner of the
9 T, O! k! U/ H) I0 N7 R/ t' E ;; world. -1 for non-intersection patches.
! `; r; K( m; w! z. i- D my-column ;; the column of the intersection counting from the upper left corner of the
: J1 b A* J8 C$ l1 ] Q: E2 l ;; world. -1 for non-intersection patches.: P+ h8 ]" V' o' P
my-phase ;; the phase for the intersection. -1 for non-intersection patches.7 y/ ^4 {' W7 \+ r
auto? ;; whether or not this intersection will switch automatically." d9 q- W" o/ J0 v0 T! q' M
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;3 |" H! p% h. W; q
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.
- f V+ R; Z5 {9 j) M. y5 ]; j;; Create num-cars of turtles if there are enough road patches for one turtle to7 Z( r4 [' x1 c0 q) g+ G3 c. `4 a! ^
;; be created per road patch. Set up the plots.& S0 [8 `. ?' N9 t
to setup+ |" k! Z9 F* X
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setup-globals
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, Z6 P. J4 L: g- x+ Q( q6 R ;; First we ask the patches to draw themselves and set up a few variables
7 l. @* Q' \$ e i8 C* g( d4 O) E setup-patches
: s7 L0 e" Z; h$ T1 B* Y make-current one-of intersections
/ a" A( x; v# x" p! ?" }3 X label-current* q1 r; x. d1 S! A3 ]9 }4 P1 U
& n2 b7 m, E5 L- _ set-default-shape turtles "car"6 {4 t! g. [$ D, }* e. c1 K
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if (num-cars > count roads) N3 ^; ^1 K# { N \- V! Q+ g
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T, U @6 L, ?4 p0 c" K user-message (word "There are too many cars for the amount of "- F1 y& u1 S- A' [ _; ~+ _
"road. Either increase the amount of roads "$ g* g6 ?# _" E1 ?
"by increasing the GRID-SIZE-X or "
) O! u( w* b) G1 d7 u( J "GRID-SIZE-Y sliders, or decrease the "- s0 `/ ?6 _' x/ b* ~! l8 X$ Z' b
"number of cars by lowering the NUMBER slider.\n"0 }9 g: Q4 v& `& z% V: W
"The setup has stopped.")1 h7 G, r; q1 a2 z; M
stop! {$ W, D2 [ q$ s9 c. b! S* ^
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color( {1 x: y0 \& b
crt num-cars3 N; C: `+ \3 z' s8 s
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setup-cars
6 x3 J3 B0 P1 s# L- |6 r set-car-color
4 r. M" _! t2 P6 \$ s record-data$ v" \/ o. L: j/ M, {2 ]$ {
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3 U8 _0 V+ Y4 K. f( M) C3 q- @7 M ;; give the turtles an initial speed
% c7 ?# M, t5 n ask turtles [ set-car-speed ] q* u9 S4 ^% m9 `4 }! u
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reset-ticks2 W0 w* M4 Z7 Q! P i# K1 w
end
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: W* V, G% b4 N' L0 ]! W' _;; Initialize the global variables to appropriate values
7 T8 i" [: t9 I& K% {to setup-globals
5 X7 K) {$ Z# r4 C set current-light nobody ;; just for now, since there are no lights yet
; ?6 O. L/ Z. g5 [ set phase 0
& N; ]) T1 ?1 Z0 x+ Q set num-cars-stopped 0' C6 m9 j1 d% y+ B9 j% @
set grid-x-inc world-width / grid-size-x% `- {8 ^0 `3 `- A- S1 F
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# {" W7 h5 M K7 Z/ u& U, H/ W, x
set acceleration 0.099
3 O& ~+ u7 B2 U7 b; T* jend
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6 R% j" L2 `1 A) B5 r;; Make the patches have appropriate colors, set up the roads and intersections agentsets,$ b9 e" P" `2 `8 ^& `" l8 n+ x
;; and initialize the traffic lights to one setting
. u; b2 H, }2 d' L+ B5 H: Ato setup-patches
, l5 V D1 ~$ X' L+ a) j ;; initialize the patch-owned variables and color the patches to a base-color
+ p% Y; {* N& S) O! { ask patches; y# [ Q; j- p) V& A( A# q' ^- z
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: Y! } E# R- k& n0 c" m set intersection? false
# c$ B, h" S" x% ^% s+ l! i set auto? false# i5 u! Y1 d- W+ q
set green-light-up? true
! V. t8 K" P5 o7 T1 N set my-row -1
( @8 D" s' H3 j" Y2 C5 Y# Y set my-column -1
2 o4 ~1 A& P8 U3 a/ e8 k' m! W set my-phase -1
* \- e3 Y/ A5 k& s0 K set pcolor brown + 3
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5 w# |6 I3 r( x: ~- ?' `4 }) k ;; initialize the global variables that hold patch agentsets: g2 L) g' G1 K" p& x
set roads patches with" I5 B! T6 y2 A+ b% Y. H$ a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 V. r: `2 B7 N7 G* l Z$ l (floor((pycor + max-pycor) mod grid-y-inc) = 0)]; W* K/ r( C3 U, D. V# |. H
set intersections roads with9 G4 E1 m t( j8 I4 u
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
) o( ^) O% |0 J8 H: | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 h$ K) D7 r6 j& e$ \" b
5 b9 e# ~* B; p5 _/ |" _ ask roads [ set pcolor white ]) |" L$ D+ L( G+ i+ w5 L
setup-intersections
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. v- U* p- ~& [3 }( {( B( y) e其中定义道路的句子,如下所示,是什么意思啊?
, X+ X; D& N& m" E9 Y3 l+ n set roads patches with
# p" m0 E) z* J! {3 z \ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
0 R* _0 m& r! R! N% P" _, X (floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 Z& V! p5 B' V' \; o. B
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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