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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。
0 g j! ~# R, Anetlogo自带的social science--traffic grid这一例子当中,
8 k/ Z2 N0 ^. Hglobals2 T% h9 H! n* W k
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grid-x-inc ;; the amount of patches in between two roads in the x direction0 M/ K! P! E* m" O( ~5 t+ h+ q
grid-y-inc ;; the amount of patches in between two roads in the y direction- M4 c% T# G4 E- W" `" e7 J
acceleration ;; the constant that controls how much a car speeds up or slows down by if
- R* T( c3 [7 y9 ~0 M s8 @ ;; it is to accelerate or decelerate
: E- X7 d5 R% {. C, s phase ;; keeps track of the phase
o: a J( f" A$ L0 F num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure ?! ~( B5 r" }8 K5 Q! G1 b
current-light ;; the currently selected light$ v, L4 {2 C0 z P
, Y Z4 i7 X3 `/ o* i) k4 e ;; patch agentsets2 r$ ?% X/ C5 l
intersections ;; agentset containing the patches that are intersections$ Y3 ?/ @* @. |1 s% M
roads ;; agentset containing the patches that are roads
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turtles-own
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* j* v/ w0 {; w$ s& z speed ;; the speed of the turtle
; t( x& G& n% m) A- C up-car? ;; true if the turtle moves downwards and false if it moves to the right9 L# L, @ o$ h& i H$ S
wait-time ;; the amount of time since the last time a turtle has moved" I+ `" x: l! n# f: j
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4 _/ [% ?, I$ X npatches-own
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2 h' F( m1 e% s5 Z; E6 E intersection? ;; true if the patch is at the intersection of two roads
% Z% R7 I; T* r+ ] c U green-light-up? ;; true if the green light is above the intersection. otherwise, false.5 M0 l$ |! Q5 [5 r
;; false for a non-intersection patches.
+ P0 T. Y! O8 y: o my-row ;; the row of the intersection counting from the upper left corner of the/ d0 \; ]& M2 Z
;; world. -1 for non-intersection patches.7 i* K3 }5 \% d
my-column ;; the column of the intersection counting from the upper left corner of the
" ]- x( W" g+ Y% D/ D ;; world. -1 for non-intersection patches.$ E5 K. X1 v& r2 | Z5 @, l% m6 O
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
+ g- a9 J& _( z1 @& s: |0 n: A auto? ;; whether or not this intersection will switch automatically.' g& P& N1 n" U7 B: {. O) U' y! x
;; false for non-intersection patches.+ v+ A. ?, r: t3 E! y, o
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;;;;;;;;;;;;;;;;;;;;;;! S2 V9 L/ F D
;; Setup Procedures ;;
$ a |: ~" I, S$ g% @6 W) c;;;;;;;;;;;;;;;;;;;;;;& \5 D0 T* ^7 `4 m0 i; r- z: A
- K9 E- s u" C! p: W;; Initialize the display by giving the global and patch variables initial values.
1 q; i) b, J! Y* c7 i+ w;; Create num-cars of turtles if there are enough road patches for one turtle to
& s/ s7 A9 C6 ^- [) G, G;; be created per road patch. Set up the plots.
* b: \2 z7 R+ J9 [3 T [to setup
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setup-globals
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7 L+ D; k$ S8 W6 x3 m4 k ;; First we ask the patches to draw themselves and set up a few variables
$ V# O* ?- D' z setup-patches
1 N! ]& W9 M, w/ K" G, ?* b make-current one-of intersections
1 [, P; B- ]0 e" J label-current; x9 S+ x7 v) C, P
* H4 |; j3 ]. @ f$ D7 d y6 i; Z set-default-shape turtles "car"/ ]* K2 V3 I: }
& I+ y: r" Z# t. o" M% s- N if (num-cars > count roads)* t8 h5 L! c, T& @" e( ]
[
; Y" _2 h) z4 a user-message (word "There are too many cars for the amount of "
5 q( H! S2 X6 n. }" P& h "road. Either increase the amount of roads "
) Q6 O" H- g! }+ ^# f1 B( g "by increasing the GRID-SIZE-X or "
8 C- ^7 n" C5 n' { "GRID-SIZE-Y sliders, or decrease the "6 R+ n7 t y* m0 F |( A o
"number of cars by lowering the NUMBER slider.\n"
! \! ?# H) v4 [# s' a "The setup has stopped.")
0 f4 T) h. x; U" R! R2 u; o stop1 I* O9 D, B5 z3 W! t% Y
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color1 X* }1 R) P: [0 |7 F% l) C1 U2 N+ x
crt num-cars
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setup-cars
! c. H- M2 U: y$ F* F% F4 O# S, ~ set-car-color: l2 [( V$ s3 J" `" z
record-data; p, S$ h4 P5 r; k2 P! \: O4 ~
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;; give the turtles an initial speed
; G$ W; N; _" b$ H3 W v ask turtles [ set-car-speed ], _; U, Y% ] h' r9 S- }' V. G
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reset-ticks
9 t: k( Y- W$ A5 [; @end
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" C$ H" M" k8 M8 S* T$ c;; Initialize the global variables to appropriate values, s0 ^5 H; u( g
to setup-globals
. P7 W R' O) Y, X- K" H5 H9 M set current-light nobody ;; just for now, since there are no lights yet6 c* s9 y; j: }- b( L) M' z6 h' r
set phase 0
8 ?6 m& @' u2 [: D set num-cars-stopped 0
' x% A, [/ L' u2 m* [/ @ J set grid-x-inc world-width / grid-size-x3 X% D; Q+ O/ u/ h" y
set grid-y-inc world-height / grid-size-y
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' A8 D' L! T- K( \* b* g ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
% ~6 v7 d; L$ k- N* u8 ~ set acceleration 0.099
7 F9 [8 K& }; l! |end
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8 d$ o, u* ~/ V6 }6 p) \" s;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
' A0 K2 `7 Z3 Y! U& G/ y \/ V/ P6 B;; and initialize the traffic lights to one setting8 s- G' Z) [. \7 h9 ?0 |
to setup-patches
0 W& c- T( W' u! y8 { ;; initialize the patch-owned variables and color the patches to a base-color3 K! I/ o( T/ x3 Q, B. s
ask patches
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" O0 {% D# S2 z: F' l3 c* _+ Y set intersection? false% k6 l- M f6 h" n0 w
set auto? false; g$ e! s0 k1 H2 I; n6 V
set green-light-up? true
* }4 R1 J! }7 R6 A$ j0 _. E set my-row -1
# ] n2 I9 E& t ?6 L2 G3 n set my-column -1/ G9 n. K9 t( A/ C6 ]7 e% G9 |
set my-phase -1
. `& [4 B6 T t) X set pcolor brown + 3- N; |2 b5 W" |
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;; initialize the global variables that hold patch agentsets0 B1 W; D. q" V& c$ w
set roads patches with
1 c6 ?/ ~5 U6 Y. k* z E" N! { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
' k9 c! `6 e) L: ^8 w& Q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" F3 |& P- O/ v& j3 {- Q
set intersections roads with0 w" d: J8 G+ y" v& f, Z% j. s: |
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
4 e- ^7 A. [1 e: s (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 `6 ~ [% j* Q
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ask roads [ set pcolor white ]
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end
: o3 h+ _0 X2 C! L6 t4 G6 Z- i/ n其中定义道路的句子,如下所示,是什么意思啊?3 i) B: O+ E, M' P' A1 U
set roads patches with% Q4 C8 I3 P: `' b3 w
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: ], j8 X; {2 g: }+ G5 a, ]9 @/ U% G (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
k! _ p; Y+ x% Y$ H3 X! q+ |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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