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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。1 ^2 X; s% h: q! p- B' _: n$ }
netlogo自带的social science--traffic grid这一例子当中,
1 @: u; @0 U$ p" n7 r' oglobals
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6 W m l; \: I3 ^ grid-x-inc ;; the amount of patches in between two roads in the x direction
; b6 p# P1 T, }/ ^0 Y1 g grid-y-inc ;; the amount of patches in between two roads in the y direction0 U6 W3 H9 c1 X+ m2 S7 N3 F' t
acceleration ;; the constant that controls how much a car speeds up or slows down by if
% b7 }/ E) h" B9 l- w# P5 `) i7 s% ^ ;; it is to accelerate or decelerate
; f/ Q1 \2 L6 ~0 \ phase ;; keeps track of the phase
% U! Q, U# w9 x) Q) f1 l% _8 w num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure9 t4 m A2 R. e, z; \
current-light ;; the currently selected light
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;; patch agentsets+ D# H/ Z% K' b6 K
intersections ;; agentset containing the patches that are intersections
: J, F7 h0 A4 T$ K, k7 H# { roads ;; agentset containing the patches that are roads& _$ l7 [5 y" \6 W7 B; ^2 M' e! r
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e1 b$ C- w7 Cturtles-own
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speed ;; the speed of the turtle
5 u1 j0 C6 B6 D5 t" r+ e" [ up-car? ;; true if the turtle moves downwards and false if it moves to the right
: S2 e; G, F+ o wait-time ;; the amount of time since the last time a turtle has moved
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patches-own; P4 ?( i2 z) L! i9 T# w
[
2 u* c/ _7 X5 i v6 s intersection? ;; true if the patch is at the intersection of two roads
$ r1 O, c( S3 l green-light-up? ;; true if the green light is above the intersection. otherwise, false.$ _) t7 {6 p% ]* h
;; false for a non-intersection patches.0 d& ]6 _) X( ?9 p& W
my-row ;; the row of the intersection counting from the upper left corner of the
/ b( J1 w. t. k v ;; world. -1 for non-intersection patches.
# |2 I& K8 s' k1 J my-column ;; the column of the intersection counting from the upper left corner of the8 S$ R+ }& [2 a/ `- |" H
;; world. -1 for non-intersection patches.
6 a7 E# \: H1 k6 c* j. k my-phase ;; the phase for the intersection. -1 for non-intersection patches., r! f+ C I8 ?& f* u
auto? ;; whether or not this intersection will switch automatically.# C @+ u% j- N3 s2 n
;; false for non-intersection patches.' k5 s" R% u/ N" E( }4 P+ m4 b
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& j$ @7 B8 I& z7 k5 L9 z: e;;;;;;;;;;;;;;;;;;;;;;: L+ j& Q/ T! C
;; Setup Procedures ;;1 m+ c) I5 {: e
;;;;;;;;;;;;;;;;;;;;;;2 n% J% Z* h' a3 U4 f; a. p: D# ?
2 r7 D6 Z) j6 x, O z;; Initialize the display by giving the global and patch variables initial values.
$ R0 V V3 }2 e W8 U;; Create num-cars of turtles if there are enough road patches for one turtle to
7 ^8 O' ^0 f. i1 j;; be created per road patch. Set up the plots.
$ I4 C8 e8 U: p* O: ato setup
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1 q! ]; u5 g5 Q9 E' }' u+ ? setup-globals# K1 y" d* k8 R% G) A
7 ^* v' v1 @ x) E$ k' ]7 B& X ;; First we ask the patches to draw themselves and set up a few variables
* o4 f9 u% k4 h& k2 l: Z( V% u* J setup-patches6 r; k- N4 z2 i* D2 H2 H
make-current one-of intersections, j4 F7 u& z: k8 H+ A/ Z8 o5 l
label-current
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set-default-shape turtles "car"
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3 ^+ v' G" d: N4 ^5 }" s if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "# h" ?0 ]$ p5 {# b
"road. Either increase the amount of roads "
2 j# S6 ^- y" S! l0 v c3 M' o9 ~( t "by increasing the GRID-SIZE-X or "" A5 i+ E; ?, i
"GRID-SIZE-Y sliders, or decrease the "
2 y8 s' n& Y. m9 f/ c$ n$ h5 f7 c0 ] "number of cars by lowering the NUMBER slider.\n", k8 m) W4 ]# e9 a- Y
"The setup has stopped.")
7 V; I0 F* f8 A8 t stop, ?' s! Y2 ~/ @4 \
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8 z4 n- V9 O' @. Z k ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color4 d) m& O5 h% f+ ]8 L
crt num-cars' d* o9 S8 y* W: l7 x+ X
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setup-cars
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record-data
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$ l" L X7 c7 W0 Y) Q6 u9 l ;; give the turtles an initial speed1 p8 a2 u; B# l r% n! i
ask turtles [ set-car-speed ]# L2 ?5 P8 \# J
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reset-ticks5 a) y9 Q5 N' P' \
end
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;; Initialize the global variables to appropriate values# }4 z" E0 {3 z
to setup-globals
?2 T5 V$ b" O/ u; \ K set current-light nobody ;; just for now, since there are no lights yet
( T9 k$ E a% o' j9 ^ set phase 06 |! Q, P7 M% G9 P" r& P3 g8 Q0 r
set num-cars-stopped 0: v. H' q. F; z- w3 U; x
set grid-x-inc world-width / grid-size-x
. b5 O0 M" S, t: ~/ y 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
" V" z7 ?5 D- P; X set acceleration 0.099
8 x$ O: s, ~, n- D) k7 W7 Gend
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
" C) \6 j9 K+ q/ ?* n' E, U;; and initialize the traffic lights to one setting
9 v% H+ A0 z9 Rto setup-patches. ]3 T# E! W- l7 V: ]: u& I
;; initialize the patch-owned variables and color the patches to a base-color
' t. F: o6 H" T) J! n) { ask patches3 P& H# \' @" v
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set intersection? false
: w. I7 ], F# X; D4 d! i set auto? false
$ _, ^2 n% g- M- m& Y9 d% } set green-light-up? true) }# @6 Z' o5 Q; }3 F0 J7 j
set my-row -1" U8 w+ F: r& F/ w6 P8 ?# t
set my-column -1
- z) I/ }0 w- A* O6 f4 Y% @5 H3 L! { set my-phase -1/ ?- X& t+ _& |6 t6 s3 H( M
set pcolor brown + 3" |" `1 o" s$ k& r
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;; initialize the global variables that hold patch agentsets' `8 o* a" h7 T$ Q7 S7 {! w
set roads patches with
) i* n4 D* I, J4 T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or# k. ]3 e `+ l/ X
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 P' K2 I% j) I" J5 v$ C set intersections roads with
/ C8 s) |1 \5 J# e& R B [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
8 e; f4 a" r0 Z( v+ p i1 R% O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]& ~0 ~) i, q ?8 ]$ g; D6 D5 U
5 c4 g9 N5 s4 f* P8 N) h( l. o ask roads [ set pcolor white ]( F/ T M7 a# x2 a
setup-intersections
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2 d9 X% I$ {" N6 ^1 t8 D6 r! y0 }其中定义道路的句子,如下所示,是什么意思啊?
; l' ?' ^6 A3 ~4 G# Y3 k( o9 D7 o set roads patches with- m" y% Z3 @3 ?. ]$ ?) {# `( {
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& z. X* g8 z/ `$ a' w# u (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 v6 Q8 T4 ]" O T, U. Y! C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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