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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。
$ ~8 D0 L3 F# {# B- j" \netlogo自带的social science--traffic grid这一例子当中,! W' F2 u5 U8 J/ T
globals9 A# A- U; j# J4 t! ~/ f3 K
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grid-x-inc ;; the amount of patches in between two roads in the x direction' ` M1 x, i v0 g$ F, S* H2 e% P2 a
grid-y-inc ;; the amount of patches in between two roads in the y direction N+ H' @% S- v. e
acceleration ;; the constant that controls how much a car speeds up or slows down by if
! ?. O2 C h. W# ? ;; it is to accelerate or decelerate
. m$ U7 t- Y& W* l/ b- T- i8 c phase ;; keeps track of the phase
! z2 a2 G4 x3 `) y3 y num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure0 U+ j4 L1 f! W2 P9 v0 G3 d! \9 }+ M
current-light ;; the currently selected light
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;; patch agentsets6 O# A8 d- n( \: \
intersections ;; agentset containing the patches that are intersections0 o9 P0 |- c1 b
roads ;; agentset containing the patches that are roads% R' V2 w0 y8 V
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turtles-own
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speed ;; the speed of the turtle% _6 V0 t6 [ h. t" M8 ?( e
up-car? ;; true if the turtle moves downwards and false if it moves to the right
8 @' I2 I1 n6 u0 _ wait-time ;; the amount of time since the last time a turtle has moved: X* Y) w9 y( q# w
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! `+ c9 Z) Y0 j4 t j% Ypatches-own4 K6 n% _* m& L
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1 e* a# n3 V, v: s, i intersection? ;; true if the patch is at the intersection of two roads+ C5 S. u7 C; m, q: n
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
$ W0 ?* z) a( V- U! k$ M8 Z: [ ;; false for a non-intersection patches.
) O5 ]) S* M* f- V0 x5 Y* ` my-row ;; the row of the intersection counting from the upper left corner of the
. o- ?! R) M' |; ^ ;; world. -1 for non-intersection patches.
+ @$ z. |5 C5 ?8 U" R0 W my-column ;; the column of the intersection counting from the upper left corner of the
+ I2 A1 A1 Y. [ ;; world. -1 for non-intersection patches.
- E, E7 D- K- @% l9 u i, c1 K6 w my-phase ;; the phase for the intersection. -1 for non-intersection patches.% M! W3 L# y9 i
auto? ;; whether or not this intersection will switch automatically.* r# i1 J; `" e2 Q' l8 c8 t4 T# F
;; false for non-intersection patches.7 L. u( V# ^4 x9 f" p
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;;;;;;;;;;;;;;;;;;;;;;
& Y& s' z1 u! \' I$ k/ a+ m) C;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.
2 y5 r' U) l1 g" w4 i;; Create num-cars of turtles if there are enough road patches for one turtle to+ r U( [! d8 H
;; be created per road patch. Set up the plots.- v' \% x0 o j$ `- Q8 r2 b
to setup
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setup-globals* e* p# Y/ B w
6 z# i, k8 c3 K2 l/ S+ d ;; First we ask the patches to draw themselves and set up a few variables
) X3 p* Z5 z/ V5 r setup-patches
1 K$ ]3 N1 C O; @! B0 T make-current one-of intersections& Q/ a9 n8 }. z
label-current
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: ]* r; D% m1 W F' M set-default-shape turtles "car"/ `& `7 b d( X/ b" t) p* T
2 K6 A5 E$ \9 m |/ N9 Z: m: E if (num-cars > count roads)$ ^0 u, s; T% d G% C# J* i# w
[
# U8 V0 k0 [. ?$ [ user-message (word "There are too many cars for the amount of "8 c1 T. I8 t4 x) R$ b
"road. Either increase the amount of roads "7 s# |2 Z$ c1 `2 s& G% X
"by increasing the GRID-SIZE-X or "4 E: h$ C/ A2 n) Y6 q6 s
"GRID-SIZE-Y sliders, or decrease the "
9 [9 V, a; `( H' J- n, | "number of cars by lowering the NUMBER slider.\n"
$ n0 J2 \/ R/ C7 G, }- A "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-color, _" [9 ~/ o' W8 @0 Z
crt num-cars
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8 ~( j5 a- Q# B% a; w b setup-cars1 u- |! q9 H' \: C* `5 t
set-car-color* [: b+ U7 O1 j4 r- A- o% }: e
record-data* A4 K( d5 K7 m( A8 I) E" P* E
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3 l( y4 }, w% C- b ;; give the turtles an initial speed5 M) o) e. D6 m; s6 ?: X& a
ask turtles [ set-car-speed ]- ], ~5 Y, f( Y( j6 |5 Z
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reset-ticks
8 V3 e& ?3 a6 K6 a# v$ R) aend
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7 G! z8 r- F: T* o' Q% E;; Initialize the global variables to appropriate values
& ]7 k. P# J9 j) z1 w2 q" Jto setup-globals
. B/ C5 F3 p' b, D! X' c S, r set current-light nobody ;; just for now, since there are no lights yet
! x! G! W" j8 a set phase 0. Z1 C! W& j; K* T3 t/ q! }
set num-cars-stopped 0' y, ?5 w9 @& z$ [6 R. P+ ^$ B E
set grid-x-inc world-width / grid-size-x
+ F. m$ s( E1 |1 P& V3 J! u set grid-y-inc world-height / grid-size-y# f' q4 Q* S, a, t% ^
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary. [+ |3 p8 T$ T
set acceleration 0.099
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6 `+ [7 a( u2 c: \1 {$ l8 o" Y;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
0 m& |. y& l1 L;; and initialize the traffic lights to one setting
y S7 |% E5 w& [7 L0 X: nto setup-patches( }$ d) o' d2 r% Z4 y& x! s* ]
;; initialize the patch-owned variables and color the patches to a base-color/ w1 j" [2 j# p
ask patches
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" B* b, C2 `. S/ K- y3 ` set intersection? false* T& B. _3 {0 H: G8 s7 X. m. U5 a3 }
set auto? false3 r% k* L- l9 j
set green-light-up? true+ G4 N) F3 E: _
set my-row -1
) x0 t9 z/ S7 r0 [0 L set my-column -1
@3 M" Y3 g/ a& g, H set my-phase -1
; j9 m6 R/ e: o3 A! |! N set pcolor brown + 3
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: a& t6 {+ V1 f7 V: P ;; initialize the global variables that hold patch agentsets0 D# f) j; l" b# c r, R8 u4 z. e L
set roads patches with: W* g/ Z# b7 e" s* v& @- K" |
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ Z1 A' D2 I5 P+ g: f, j (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
7 I1 ?- |1 \5 P* i, T; r set intersections roads with7 x- Z$ ?. |9 Z' B* h
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
( T, i. U! @3 }7 \$ Z" T' R# ] (floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 }$ Y& T* ^ x) C$ t2 A, X- q
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ask roads [ set pcolor white ], _/ h8 ]! |( K" s' L
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?) E9 p; p* ^! H. W/ t1 O, s
set roads patches with
o/ ~* I+ @( m& j) E! m: k. y" O& Z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& L+ B$ c" A- V: `
(floor((pycor + max-pycor) mod grid-y-inc) = 0)] f ~ K5 T: A- P0 C9 H0 N: ^
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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