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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。
. _5 e. o2 q$ G2 I3 N `5 N* snetlogo自带的social science--traffic grid这一例子当中,8 i" z2 j" c2 k5 ?$ d
globals
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/ _1 d1 o9 ]1 ]' ]% s grid-x-inc ;; the amount of patches in between two roads in the x direction
( m+ O: W- C: B0 |. }. p grid-y-inc ;; the amount of patches in between two roads in the y direction" `, P2 G; T5 m# f( R% \
acceleration ;; the constant that controls how much a car speeds up or slows down by if
. I5 k0 ?9 Z# G2 |! ~4 A ;; it is to accelerate or decelerate! i" z# p/ U* l8 b8 ~
phase ;; keeps track of the phase
: i( S, s- y. h! ^4 {, X+ E# G num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure6 D- `8 p( E6 i5 Z5 s2 r) _: @
current-light ;; the currently selected light
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;; patch agentsets$ j+ L+ B$ M# a- T& Z& W
intersections ;; agentset containing the patches that are intersections
8 S6 r) {: J' t3 {( H8 z. J9 k! a roads ;; agentset containing the patches that are roads
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turtles-own" G+ M8 w3 z0 s* K* `* k2 P. w% @
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speed ;; the speed of the turtle
% _3 C6 _ R1 [ up-car? ;; true if the turtle moves downwards and false if it moves to the right
4 U/ o; p K4 R s2 m7 H wait-time ;; the amount of time since the last time a turtle has moved
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patches-own0 i' r- D W( |( @, B- s1 R- {
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intersection? ;; true if the patch is at the intersection of two roads
& j( z7 r, y4 ^: ? E9 x" w E: T green-light-up? ;; true if the green light is above the intersection. otherwise, false.
& j7 ~ u" e, ^2 E4 T! S4 A ;; false for a non-intersection patches.; y+ }) l/ s; h: {
my-row ;; the row of the intersection counting from the upper left corner of the9 F, }, J8 U( C
;; world. -1 for non-intersection patches.6 M/ @! \/ | F0 L+ t" } S5 ?: W9 s
my-column ;; the column of the intersection counting from the upper left corner of the; A, ?: [: x9 g/ c% q
;; world. -1 for non-intersection patches.% z% t" q, f* l$ q
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
. Z9 j0 a9 p D, N auto? ;; whether or not this intersection will switch automatically.1 J& `. _) O; Z4 {& y
;; false for non-intersection patches.: f$ c) M/ B0 H% k# g3 z
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' w% x/ V. |) X z. L1 v;;;;;;;;;;;;;;;;;;;;;;- H/ P' y4 @5 ~" X
;; Setup Procedures ;;
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' g% v- ?9 u( k ~9 G& s( p( _/ I;; Initialize the display by giving the global and patch variables initial values.
8 S- S8 Z- q2 W( \;; Create num-cars of turtles if there are enough road patches for one turtle to
N5 g' n+ y5 N2 z! z% [( P6 F;; be created per road patch. Set up the plots.8 ~6 r4 p) p: K, @5 ]" p0 j
to setup$ J: N" C" T. ?! H% p
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setup-globals; y! L m! e% n& s$ g( h
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;; First we ask the patches to draw themselves and set up a few variables
9 p0 M' Z+ z f% u& W setup-patches2 X" o6 m; w7 x. Z* G
make-current one-of intersections
6 ^+ V( E3 n/ T, G: w6 k& ? label-current
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9 r- q* u7 A% x set-default-shape turtles "car"; Y- b* \( N8 `6 a( c% E) ~
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if (num-cars > count roads)- J( b! G$ L3 e! d. R% P
[
3 i9 B! F; n! l! } user-message (word "There are too many cars for the amount of "
2 k1 Y' m2 J; e# T "road. Either increase the amount of roads "
! M+ T7 r0 q' j2 d g "by increasing the GRID-SIZE-X or "0 W: {# A6 i, K# i/ G( h$ ? l5 j9 @' c
"GRID-SIZE-Y sliders, or decrease the "
: y2 u' \# V p" H+ e "number of cars by lowering the NUMBER slider.\n"
* J7 s/ A8 Q& k9 N( O! W _8 _3 I "The setup has stopped.") R, G( B2 i1 a
stop o g* \; P6 \$ |
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0 J4 D' X$ E: I' A ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 F: G! a) C0 _ crt num-cars9 N2 I4 u% P/ i; B
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setup-cars# ~' r) ^* V* A1 p1 q
set-car-color' q) x9 @! M* ?# N
record-data4 ^3 H, E8 Y/ o1 M$ n: [
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8 h/ }7 ?: o2 m ;; give the turtles an initial speed v: {2 H: a# W+ |- y
ask turtles [ set-car-speed ]5 ^2 J; x/ j. ]
8 Q! F" X& f! o reset-ticks
/ ?/ k1 c7 o" S- m/ uend
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;; Initialize the global variables to appropriate values* s d. [4 E3 D: \# E0 V
to setup-globals, i* b |1 _5 X' i6 W. V7 K K
set current-light nobody ;; just for now, since there are no lights yet
?: B @3 b' p& P4 d$ u! L$ d set phase 0; g, b3 H3 f* B* J
set num-cars-stopped 0
* E" { f, x. a% C" s2 y O2 ^ set grid-x-inc world-width / grid-size-x6 ?6 ?% }7 s/ A7 E X9 C
set grid-y-inc world-height / grid-size-y) ^( A5 j3 l/ A
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary; \4 M6 u3 {* w& b3 r6 Q) D" u
set acceleration 0.0991 ~9 ?1 ?/ A, @- Q& v
end
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' U$ V" c$ {5 N4 K- m9 P3 |;; Make the patches have appropriate colors, set up the roads and intersections agentsets,# T, k6 u6 y2 h& D' U" o( {6 E
;; and initialize the traffic lights to one setting
) v' K) X2 Y- U2 q, p% hto setup-patches! p; C2 j, R* ~
;; initialize the patch-owned variables and color the patches to a base-color
" k7 | ?( |, v: d* a+ G+ Z ask patches
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set intersection? false& W6 q1 \5 G/ l
set auto? false: t0 r/ Y9 ~, e; l; T8 o$ t6 v$ p9 `
set green-light-up? true
6 \, R! h) m- K- s4 T0 x0 t2 } set my-row -1# \- S" {' r; [/ F7 A, d! b( D
set my-column -1
! J2 m6 w# h. x, G set my-phase -1
8 L: e$ N& R2 W' e4 g0 y' ` set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets/ A# ~( t$ q. X8 o$ b" W
set roads patches with
% a4 ^7 L: F# m+ q! C# b( y [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or! O5 B4 [' S# v% o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)] z4 Z; ?* E$ @1 [
set intersections roads with% E' n1 A2 D# F, [: x: S2 ~! q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
9 Y! B, x7 s2 Y& o (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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7 C$ C1 [2 Y2 n; x ask roads [ set pcolor white ]
1 N* A8 [. {$ {; V: U0 \ setup-intersections
# `4 u1 i( [. c. ?& G5 Lend
0 i+ A) K* ^; ^4 d其中定义道路的句子,如下所示,是什么意思啊?2 M& w: b1 q) r2 Q- o9 [! ]5 I
set roads patches with* H% Z* @- e) G, Y) G' _. ?
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 D; o1 b* l8 ~9 O! T0 C; C9 J
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]: g% t! ^" g( N) T
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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