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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。
. M+ u! E: A( m4 jnetlogo自带的social science--traffic grid这一例子当中,
$ B; p7 }) ^" b6 E1 iglobals- ^4 Y" A2 |3 d; l
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5 p) M2 \6 H* N4 I$ f grid-x-inc ;; the amount of patches in between two roads in the x direction: s2 u- i q- H
grid-y-inc ;; the amount of patches in between two roads in the y direction
- f7 R0 }3 q, N% z acceleration ;; the constant that controls how much a car speeds up or slows down by if, l, z. v) [# m7 p: r7 U$ n
;; it is to accelerate or decelerate
1 u2 k& L3 n) l* x: [- C& e phase ;; keeps track of the phase
( Q7 p9 e. k1 x8 ]3 {& D% d* u num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure: ? P. _3 y3 a9 f0 c, r- S9 z
current-light ;; the currently selected light Z2 [7 x( D4 `6 I/ c
# X) {- f- _, n# ^1 {6 @ ;; patch agentsets
, G0 d" l3 K5 D! y( z& \ intersections ;; agentset containing the patches that are intersections
- R' h6 R8 ^) Y" l7 O" ` roads ;; agentset containing the patches that are roads. g1 b$ A/ V1 X8 S z% M# r4 m
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+ Z+ ?" `( Y, }turtles-own
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" R5 b8 _2 H6 D$ R Y% D+ F speed ;; the speed of the turtle: T0 B) N+ s$ W. ?7 v) m
up-car? ;; true if the turtle moves downwards and false if it moves to the right: U n- {9 M f7 x) F9 H" O" `+ P
wait-time ;; the amount of time since the last time a turtle has moved" r/ ~" p+ N3 M/ l0 C( g+ u
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7 k& w) z+ G$ f4 I2 `8 Epatches-own
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7 h" {) w e" g& z( p intersection? ;; true if the patch is at the intersection of two roads& _; e: ~6 |0 x6 x2 h
green-light-up? ;; true if the green light is above the intersection. otherwise, false./ G/ c ^! w8 f
;; false for a non-intersection patches.
* Q, U1 ?9 ^% b7 s my-row ;; the row of the intersection counting from the upper left corner of the* a% p! D% A9 `5 e+ X
;; world. -1 for non-intersection patches.
9 I( P$ @' u8 n' | my-column ;; the column of the intersection counting from the upper left corner of the. W8 `1 X3 A" K a. Q3 A! f. J. [
;; world. -1 for non-intersection patches.5 V* i9 U. @0 g, \6 j+ f
my-phase ;; the phase for the intersection. -1 for non-intersection patches." a1 o: F" O4 A9 @
auto? ;; whether or not this intersection will switch automatically.
m: Y% b9 m, n ;; false for non-intersection patches.
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8 x$ U! q: H: n) W0 K" r. E;;;;;;;;;;;;;;;;;;;;;;
8 z# A/ V$ X M0 r( }) A;; Setup Procedures ;;
7 ^* B k# H$ g+ F2 U k: z;;;;;;;;;;;;;;;;;;;;;;9 b# g- \5 w5 l8 F Q H6 @
* C, |$ P) h2 V' |;; Initialize the display by giving the global and patch variables initial values.- Q6 r! _: s: L6 F* t
;; Create num-cars of turtles if there are enough road patches for one turtle to
2 x, E: B! [- c;; be created per road patch. Set up the plots.5 u9 e( Y# t2 n
to setup% ?3 V5 R7 j" G5 J- ?3 F) ^: T, E; R6 ^
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setup-globals) s) a3 {7 E+ ]4 e, Q/ n
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;; First we ask the patches to draw themselves and set up a few variables' B% P1 F* a8 A! g. |
setup-patches" h1 P0 D/ K$ x' y& l5 P' O! X$ ?
make-current one-of intersections& a! [; n7 q. A3 I9 q8 y+ L
label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)0 I2 x. n9 `0 I5 D& q+ m3 Z
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/ j2 h5 l) j! Q user-message (word "There are too many cars for the amount of "7 K6 U/ `* ]9 a( H% J5 X
"road. Either increase the amount of roads "
/ M' g6 I* G1 Q9 s# q "by increasing the GRID-SIZE-X or "$ h, o4 D" d0 o: l1 n5 |! l
"GRID-SIZE-Y sliders, or decrease the "
! [, ^ x# r. g& N4 u/ T "number of cars by lowering the NUMBER slider.\n"
; K$ n, b# t3 x8 U8 ^3 ]) _% F "The setup has stopped.")
% [7 s; D/ K+ w0 m4 O stop
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& _8 p: s- Q8 M6 h. m: P9 p/ Z ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
) v% ^1 T7 B; e2 [4 a" ?6 X r crt num-cars, H Z. g! {/ w+ m9 d
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1 P: G' e2 ^9 T! D' t setup-cars
9 b, S# h" |- v1 t set-car-color
0 l: e n9 h. W1 m! K, m record-data% ]* H! ^: H7 h4 {5 w9 s! N
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- |; p9 g) q! c) P7 p ;; give the turtles an initial speed% H- r4 s& p7 {6 h$ C
ask turtles [ set-car-speed ]6 `- w. J( B) r' f
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reset-ticks t E% P# c2 o# ~+ u( L' {
end" w& p+ @ n9 i# p" P% b
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;; Initialize the global variables to appropriate values- p3 P% `8 x* a) }. ?8 E/ D
to setup-globals
- X+ S$ }/ V+ ~7 t set current-light nobody ;; just for now, since there are no lights yet
" `. Y" `6 B5 o- [: n set phase 0( M6 o1 B/ c9 k) O: P$ ~
set num-cars-stopped 04 ~* |6 t# Z* p9 W4 f
set grid-x-inc world-width / grid-size-x- S# E) ?6 W3 [1 _
set grid-y-inc world-height / grid-size-y
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. }$ I, _, ^$ ]# \# ?" m, g ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary* l# q% U4 ~: z
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets, P% z* D7 q; H5 h1 u; n
;; and initialize the traffic lights to one setting
Q- d7 V# T- a; Yto setup-patches
y7 G1 V" W+ v* {+ N ;; initialize the patch-owned variables and color the patches to a base-color
$ E; m. R" g6 N. X8 Z ask patches( B3 Q& _2 h1 B
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2 ]6 ]3 d, [% G: i3 B8 Z: u set intersection? false3 o3 I* h6 n6 ^4 M ^
set auto? false5 G i% V; O0 z: c
set green-light-up? true
# @& E% {1 F+ N4 B. |8 h1 F set my-row -15 P) F/ q9 Y. Z( z1 \! ~& j: [2 b
set my-column -18 c R, b/ q% g" o
set my-phase -1! y; R% G' f: Q( l% f
set pcolor brown + 33 J9 O p% |- l6 G' M8 Z' C
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;; initialize the global variables that hold patch agentsets
6 e8 j( |' @) K9 o- q set roads patches with3 w* G- y' J, h# {# |/ U
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or2 u0 l9 O6 n8 A8 d$ E7 [
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]3 w$ k/ P7 ~' K7 G/ {: L9 Y
set intersections roads with
( C% v3 J1 m; u$ ]' j7 a [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
' _2 `! W+ c" l* p) C (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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' v0 N2 U9 U+ g3 ]* `3 l. L7 r } ask roads [ set pcolor white ]
4 A l# w. ^# F" N U- q9 ~ setup-intersections N9 J2 Y5 c" Q& ^* B4 e9 i
end' J. v0 y: B1 B! C4 ^
其中定义道路的句子,如下所示,是什么意思啊?3 |& o& e2 x+ O1 A% k/ K0 L+ d9 T. y
set roads patches with
! o( D/ G9 l+ F0 O7 \. Y [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
' [ F/ D4 m/ Z3 J; O+ c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" u. o1 r8 D8 K: x0 C; t0 m
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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