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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。
$ U; N' Q) d. S7 h- Mnetlogo自带的social science--traffic grid这一例子当中,
4 N& i' B9 Z) xglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction) i3 D: ~, q$ _( } V1 ~" S
grid-y-inc ;; the amount of patches in between two roads in the y direction% `. Z. }) R; G5 B0 R `* _* _: _( `
acceleration ;; the constant that controls how much a car speeds up or slows down by if
! _1 D9 Z. s+ N/ a( I ;; it is to accelerate or decelerate
, G M; ?! C8 X _8 g' r phase ;; keeps track of the phase" \, c" z3 @0 I* L' Y6 T3 r1 k( y
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
1 T9 h: n" ^3 |# V! N3 L current-light ;; the currently selected light
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;; patch agentsets3 E5 C7 h5 B& b6 l/ G7 h, z
intersections ;; agentset containing the patches that are intersections, o+ R# z7 r2 @0 M: ~
roads ;; agentset containing the patches that are roads1 ^4 K1 s) E4 ?6 T% s: `% L( L7 {6 ^
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turtles-own6 O' v5 H0 f8 D4 s
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speed ;; the speed of the turtle
; g* g; t0 P- O3 o1 C& V3 P- { up-car? ;; true if the turtle moves downwards and false if it moves to the right
- M( s0 V5 Z y% Y# Z wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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( Z+ D$ c3 x' }8 G K' M! c intersection? ;; true if the patch is at the intersection of two roads$ N4 }# \/ i+ c
green-light-up? ;; true if the green light is above the intersection. otherwise, false.1 T6 v" D |9 O5 i8 e- C
;; false for a non-intersection patches.+ l9 x! F! [/ s- t$ `
my-row ;; the row of the intersection counting from the upper left corner of the
# O8 s$ B6 H5 u5 i# ? ;; world. -1 for non-intersection patches. C0 g- G" u9 [4 ?8 c7 c+ L6 B5 x
my-column ;; the column of the intersection counting from the upper left corner of the4 f+ ~0 f6 a- {0 y. d$ Y5 f* x
;; world. -1 for non-intersection patches.1 P. e. u0 A. j3 y
my-phase ;; the phase for the intersection. -1 for non-intersection patches.( M+ U0 n. E/ u; l( J
auto? ;; whether or not this intersection will switch automatically.* ?. j$ b# Q& g$ c" T6 I
;; false for non-intersection patches.
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8 S0 ^, `) C" F;;;;;;;;;;;;;;;;;;;;;;4 o' I3 I/ d) X& U* r- }' G0 `! z
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.: J! C6 s) T+ ~" i2 U
;; Create num-cars of turtles if there are enough road patches for one turtle to
4 Q; m/ z, t- A. A. {( ?;; be created per road patch. Set up the plots.
' g& z) ^) |$ o$ g+ A9 D6 p) [to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
. I0 R9 Q! ]! ]4 ~; Q setup-patches. a3 j. [! h4 V8 c
make-current one-of intersections8 N4 ~% }4 W- f6 M/ c% d& u
label-current
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; |5 h8 y; f: R5 b; B6 {: i( Q) ~ set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "8 g- n" K k& D5 C9 G9 ~% d
"road. Either increase the amount of roads "( l' A6 @9 J, }: `9 q
"by increasing the GRID-SIZE-X or "' G/ K) M# E1 E
"GRID-SIZE-Y sliders, or decrease the ") u$ e5 e% U% p
"number of cars by lowering the NUMBER slider.\n"7 u8 ]! a0 @+ D3 a/ h
"The setup has stopped.") n' A/ H/ {7 ]. K2 f0 r& A
stop
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- N: e' \+ U) j F3 C ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color- ~5 U1 T8 t ~& F5 T3 m
crt num-cars
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% ^( U" m/ J* A# _ setup-cars
& u* q# y6 t F- n3 _ set-car-color' v: `2 I, `# n( K% f6 p
record-data0 Y9 n% h; N* V* W
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;; give the turtles an initial speed
$ h$ ?& U0 V. w+ g/ @- r ask turtles [ set-car-speed ]4 @- w, U) T. ?+ y" t
! Y- Z6 B8 W, N8 J reset-ticks
* m3 O {0 w& Y8 Iend
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;; Initialize the global variables to appropriate values
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3 d: x$ o' i9 d: c set current-light nobody ;; just for now, since there are no lights yet. T5 f4 E \9 j. H2 }. I- ^
set phase 0
3 h& \2 I$ [# z9 ]5 _; e, ?! `# p set num-cars-stopped 0
( f* V _0 M. _8 Z! ? set grid-x-inc world-width / grid-size-x9 [. R5 ^, H+ a4 G- o3 S g
set grid-y-inc world-height / grid-size-y
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/ l4 R8 o; [6 u, k% f1 }4 l! ]. }' D# H ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 N( P0 c3 N9 O2 s
set acceleration 0.099$ @! V9 Z. t/ ]4 y
end) {; e% S' V- F* L2 P
8 v7 e1 d3 f J8 X5 N4 I;; Make the patches have appropriate colors, set up the roads and intersections agentsets," F- Z3 j5 p( w' U! u. ?$ Z* c
;; and initialize the traffic lights to one setting+ Y e& ~2 d5 C) O1 |
to setup-patches
( Y3 [! m8 n0 n ;; initialize the patch-owned variables and color the patches to a base-color7 Z* }$ `- [% c! l& }
ask patches( }" i" w0 \' z
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set intersection? false
# U; {' ]6 A1 g* } set auto? false4 |; M0 A; a& M4 I; ~' I
set green-light-up? true! Z; i0 L3 P8 L8 x! L/ D/ n
set my-row -11 f2 l. G& P( Z; P9 |/ Q2 Z
set my-column -1
4 L3 Z! `0 V* G( `7 y$ p' I2 B set my-phase -1
# S; @9 D* o& V1 z6 G set pcolor brown + 3- H2 ~0 t& r9 {- B
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, [8 Z J" J5 Z5 Z! p( _0 D. L ;; initialize the global variables that hold patch agentsets+ l* C; E1 |$ G# C3 q
set roads patches with
$ Q- P, h( _! `, E3 x3 S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ @ w/ S7 ~; v+ L* O$ x5 |+ Y (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 I: W+ i( n5 Y; ~ set intersections roads with- X5 V! [! w/ P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and! t, l" U& e: x0 w- d
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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" X1 h5 A; ^& u其中定义道路的句子,如下所示,是什么意思啊?
: t2 J6 L8 M# n" w# T' S$ A set roads patches with
5 E3 I! m/ V5 c* n) @ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
2 a! B6 K' D% B- R (floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 k7 \, ?/ ]& a! n, W7 G4 ^) ~
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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