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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。$ Z! ?2 R2 q# R3 \0 n J
netlogo自带的social science--traffic grid这一例子当中,
: J% B" q0 R3 E5 x x7 kglobals: P6 L; W' ]/ [+ W
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grid-x-inc ;; the amount of patches in between two roads in the x direction) A% \$ _4 J0 o& p# \8 n8 w0 h
grid-y-inc ;; the amount of patches in between two roads in the y direction
" y9 @6 c1 o; M0 e ]* I acceleration ;; the constant that controls how much a car speeds up or slows down by if
3 X" I& F! ~0 b$ x# G ;; it is to accelerate or decelerate- [" h- o( W* K
phase ;; keeps track of the phase
$ K3 A7 g0 o; V, N) r num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ `2 L6 K8 V6 G# n3 L# S4 {2 `
current-light ;; the currently selected light
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;; patch agentsets
' Y6 [: X {2 j( C. ~ intersections ;; agentset containing the patches that are intersections
5 [% O) ~0 L* c$ v8 M; `5 q roads ;; agentset containing the patches that are roads9 f0 ]7 Q1 D6 M; N" e1 W- z
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turtles-own
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, m& y% O9 K- n6 i2 \; k+ W speed ;; the speed of the turtle
$ G( D1 o. o6 p: c2 k5 Y up-car? ;; true if the turtle moves downwards and false if it moves to the right" w" ~) p+ l# }0 S
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own; H* C' T* r1 i0 E6 P& s" ?8 _
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+ c" q% d: z. E/ g+ q# [ intersection? ;; true if the patch is at the intersection of two roads2 |1 A' L" X1 c+ L, _
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
" g7 I) k- K% P ;; false for a non-intersection patches.) H, d( Y# s3 A
my-row ;; the row of the intersection counting from the upper left corner of the, t T8 i/ J) P0 k) S7 B0 ?3 o; s
;; world. -1 for non-intersection patches.3 k2 t# C" Y5 ]# m3 I L- X
my-column ;; the column of the intersection counting from the upper left corner of the
( D6 K* l- I$ y, M. M ;; world. -1 for non-intersection patches.
: T& ~0 y& y$ G. z. a* g1 r my-phase ;; the phase for the intersection. -1 for non-intersection patches.7 j7 T/ F1 S8 F) L( `* E; P* n
auto? ;; whether or not this intersection will switch automatically.
/ d0 _4 c% N0 C+ l3 e, m ;; false for non-intersection patches.9 ^' Y+ P+ e' t- X2 f- I/ {
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;;;;;;;;;;;;;;;;;;;;;;
1 I+ {% s f& }6 A( z: m;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.: Q1 H1 h* K9 `) n9 m. @
;; Create num-cars of turtles if there are enough road patches for one turtle to
! W9 Z) E$ w" H9 F" T;; be created per road patch. Set up the plots.) h" U6 H6 }. a3 C. h+ B+ M7 n, m0 {% m7 I
to setup
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$ {7 R9 D1 B! U4 m& a4 x setup-globals; H5 N$ B4 w) u; v3 W- J7 G
1 w0 S- P! T- ^ ;; First we ask the patches to draw themselves and set up a few variables2 `; \$ y* L' r8 V0 V& o" C
setup-patches1 S; ^/ i: ~( D* r
make-current one-of intersections
% \: f; B e# |* `5 L4 Q* D. x( [ label-current; h7 s: E5 \% G! N& Z
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set-default-shape turtles "car"
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if (num-cars > count roads)) B" k1 C- }. q
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user-message (word "There are too many cars for the amount of "
; K/ G0 ^* e7 A% F# H "road. Either increase the amount of roads "" b; |! Q o, q# x( S( {" K8 F
"by increasing the GRID-SIZE-X or ": I7 x6 Q s" h8 x
"GRID-SIZE-Y sliders, or decrease the "
! ] E* @5 F0 l/ k M4 D "number of cars by lowering the NUMBER slider.\n"7 O& H2 m9 o3 w0 ~+ {6 ]
"The setup has stopped.")7 t7 F. K* e x1 P( B. ~: L6 s8 L, I
stop
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6 c K6 M/ E( O ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color: i$ E0 I" P( W0 z1 u* [
crt num-cars
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setup-cars: s, ^+ i7 F. _2 r# p1 V) {' s! s
set-car-color! b8 c* w w( t0 T* \ K
record-data
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;; give the turtles an initial speed& |" ?% V% O+ v7 O8 M
ask turtles [ set-car-speed ]7 O; Z% A' y- l* y; b/ M/ _
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reset-ticks; z. M2 }5 P; J6 ?
end1 \) k' y9 {9 T9 X5 \# |4 c
: u1 Q% A) z. `+ F4 U1 W;; Initialize the global variables to appropriate values
. E( O2 J' b, Lto setup-globals; N2 i5 z3 Z, \; c& g/ S1 a% E
set current-light nobody ;; just for now, since there are no lights yet% v6 k1 ^( ^- N
set phase 0" v3 J0 Z" W. v0 g: G+ V& b
set num-cars-stopped 0
2 v* y: h% O5 y+ X0 o set grid-x-inc world-width / grid-size-x
* |2 s) O6 z6 l* Y& j set grid-y-inc world-height / grid-size-y _% g: S* Y+ ]- r
w$ l2 A" _1 u ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary7 _, x7 W: A1 U- ]8 _! L6 ^
set acceleration 0.099
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: C. V8 g; O- L7 w7 {;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 P* M8 V7 e/ {: q
;; and initialize the traffic lights to one setting/ s4 \$ f: s) X
to setup-patches" e8 R" Q- r3 Q, T1 A, w1 O+ v
;; initialize the patch-owned variables and color the patches to a base-color( V0 X U7 u. V) [; C/ c: w3 K/ w) R
ask patches- K: d* x( B% ^' W9 L* B/ E
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9 U+ O: J; v: M set intersection? false
& x4 A) I: j$ o' L: U set auto? false
' a0 H& G& q$ ]3 ^$ r( c set green-light-up? true
8 U( J1 j6 M8 c( T9 j' k' b set my-row -1
( ]$ o3 R6 F6 L/ P' A# C' a, x, q set my-column -1
1 Q- S. W1 V/ Z$ l* S ^ set my-phase -1 U5 M) t% O) T* b# J! ^2 G7 s9 o$ B8 \
set pcolor brown + 34 y4 B& Z# t" |! |" W9 |- r' k6 W, ]
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. k6 g* L% w7 l+ k& G/ i; V2 q ;; initialize the global variables that hold patch agentsets( {: }, ^; c' i- ^& w: n
set roads patches with4 t* W, K z2 K/ s5 R- H( {, `' U
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. S8 c# B3 O8 R, Z1 h
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% x1 r1 g2 P. p7 i
set intersections roads with
( O4 j: o; x- Y. P [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
9 a& K5 ]# U6 u0 A1 R F! @ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]* l- m6 l" V; Q& c7 V5 P
setup-intersections
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; V' N3 A6 x/ B其中定义道路的句子,如下所示,是什么意思啊?2 w' a' O: ^$ n- r% l
set roads patches with' E5 I; n! L7 c: B2 B4 J. `! t5 M `
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or# H4 Q+ M; G% E' ~/ C* L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: m7 v6 ~: R. i0 p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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