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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。
A7 M* Y, ]% I6 X) i" Tnetlogo自带的social science--traffic grid这一例子当中,( m9 C* N2 N2 z: L0 F- O( i7 ~: I$ j
globals. d {. M7 V# \" q1 a- s
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0 L/ f6 V: k! ?1 u grid-x-inc ;; the amount of patches in between two roads in the x direction
9 Y; }/ ?$ w- G5 O2 X grid-y-inc ;; the amount of patches in between two roads in the y direction9 l" k4 Y) B, t1 W1 Y5 I2 {0 r
acceleration ;; the constant that controls how much a car speeds up or slows down by if
2 `. v& a& G7 H- y" M, J4 k ;; it is to accelerate or decelerate
" O) Y) L8 D/ P; P phase ;; keeps track of the phase! G, d, b# Y7 g
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
5 i; i" X: @2 l) H* i# m current-light ;; the currently selected light) N: D9 E/ {4 D$ U" C) U
X( p6 S$ q% G2 w4 J8 a' u5 j ;; patch agentsets+ q' p& M0 x: N8 k m
intersections ;; agentset containing the patches that are intersections9 G8 h! f2 Z0 Z9 D
roads ;; agentset containing the patches that are roads2 |; m9 z* U# U; Q8 b8 a
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turtles-own" v0 q0 G" L6 B9 F( E
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speed ;; the speed of the turtle
3 O. Z+ B* \4 H+ P1 M8 e up-car? ;; true if the turtle moves downwards and false if it moves to the right2 p. F; L; }) B ~0 A* O
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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0 X3 w; y# W' }4 e% H6 D/ R& L intersection? ;; true if the patch is at the intersection of two roads# Y5 w5 @' b6 t% ?! V
green-light-up? ;; true if the green light is above the intersection. otherwise, false.7 J# I: R; Z7 N' O$ O
;; false for a non-intersection patches.
* n" g i$ F8 q' V my-row ;; the row of the intersection counting from the upper left corner of the
" e F% q6 o0 n0 Z ;; world. -1 for non-intersection patches.
1 B3 @3 I. Y3 p my-column ;; the column of the intersection counting from the upper left corner of the) [/ M5 c# v9 _
;; world. -1 for non-intersection patches.8 p$ K: e8 T/ b, {4 O
my-phase ;; the phase for the intersection. -1 for non-intersection patches.8 r, R, m- ~ _3 G9 M7 c! B2 t
auto? ;; whether or not this intersection will switch automatically.
7 B0 F6 I1 Q9 Q L ;; false for non-intersection patches.
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u0 V# F' i: Y w;;;;;;;;;;;;;;;;;;;;;;
o) U7 D" l- o" [; F;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.; N0 E3 y5 f. C2 }% s
;; Create num-cars of turtles if there are enough road patches for one turtle to1 D+ b3 l( _6 y) m. H
;; be created per road patch. Set up the plots.
: c& L3 t$ n0 [& P! `to setup: e X; S& N4 Y! z
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setup-globals
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# e3 B* G& T1 G5 t0 k3 ]$ X+ _$ O ;; First we ask the patches to draw themselves and set up a few variables; q8 h' _! E8 r
setup-patches
- u. |* `# r0 H+ f1 l& g make-current one-of intersections& d# r, h! N1 s5 V a* A
label-current
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set-default-shape turtles "car"; Y- X, C) ]3 i
; b% O4 K% c: D1 f2 l$ J) ^ if (num-cars > count roads)
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8 L. d: Q4 e& \2 k8 x- J1 S* x user-message (word "There are too many cars for the amount of "# m/ B2 j% Z; ?8 _& X# T
"road. Either increase the amount of roads " a. |: s& w0 M5 N" K
"by increasing the GRID-SIZE-X or ", R9 m5 G& T3 J0 c
"GRID-SIZE-Y sliders, or decrease the "0 j. s2 [& `6 ?8 z
"number of cars by lowering the NUMBER slider.\n"( O' }+ p% f! Y0 b' Q# J
"The setup has stopped.")2 e5 W; B* U" N
stop: L* N: q5 u5 q9 I2 ~
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color1 D; R* n1 ^% \$ n, J7 O
crt num-cars5 Z& ?7 k& B$ z' q! \
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setup-cars
4 t5 A! L S+ E9 q9 ~( `. D set-car-color/ d* O. E- }5 s* n& ]7 g2 H C( j# d
record-data) @ |4 A/ w; x. B. Q+ L
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;; give the turtles an initial speed
; f. x% r0 {- h0 k; k1 Y ask turtles [ set-car-speed ]
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1 E( r9 g) `0 C reset-ticks
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;; Initialize the global variables to appropriate values
9 U: I& x& r/ s b7 C$ Zto setup-globals
+ ?% E0 r+ Y$ ?/ \$ ^: Y; O set current-light nobody ;; just for now, since there are no lights yet1 E2 ]9 _0 n3 h/ e2 U* r
set phase 0
9 `4 f. @6 C3 W set num-cars-stopped 0
; f! ]/ ~: y2 F P U set grid-x-inc world-width / grid-size-x/ l; m& N. |4 y! o. l4 h- l8 j- ^
set grid-y-inc world-height / grid-size-y1 W; V$ C; c) v5 K4 P( g9 C2 _
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
$ N. s. i A4 d$ J3 U7 _5 x set acceleration 0.099
) e+ S8 a! M7 bend# G* X) g x) b9 ?! _* k1 s3 m4 U
" @7 i' j, G+ ]1 a;; Make the patches have appropriate colors, set up the roads and intersections agentsets,& _% N- ], B& j! J0 K* w
;; and initialize the traffic lights to one setting5 i9 C1 G |. s' I5 v- b7 ^
to setup-patches
- M6 Q% k& D9 D3 a ;; initialize the patch-owned variables and color the patches to a base-color
( E: B2 c9 D+ W( N ask patches" x6 g/ r' s8 |, G8 d0 {7 E- }( P
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% T+ r% J2 c! P) D+ H set intersection? false
( ?: T% X' o) |9 ?3 f set auto? false* }3 C6 E* `6 Y7 f4 k! }
set green-light-up? true
* J$ c! X7 ]# _ set my-row -1
8 L7 b5 z# Q& M set my-column -1
% J' X1 l z" w+ z set my-phase -1# i/ {' o! ^' D7 C% P7 _
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets) V( S7 f% O( _# z* h) f& c
set roads patches with
9 C4 W8 f" m8 z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ n: r. ^ n) B: @8 j+ `' p6 ^ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 ^% [/ \/ `) O% h3 L0 z set intersections roads with) S2 f4 Z( @/ I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
: f( h# U0 b- X m1 e/ s! d (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 v# e. K& w; P0 J) Y1 e
( \, O/ Q4 ^/ D/ l5 I. @, \ ask roads [ set pcolor white ]
6 v L6 m. O& B. s5 h! g setup-intersections' m# x& @/ ?* t4 i& [
end" H4 }! P% z/ d+ G9 s' ^9 S
其中定义道路的句子,如下所示,是什么意思啊?/ C) ]" O6 L# Y7 K# `0 z6 j
set roads patches with
/ J0 j( h8 o8 Q& s [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or0 S `7 d: _; _: ^4 W7 z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]: z, o8 h) |& `9 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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