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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。
, x( V, c" s' E* n& gnetlogo自带的social science--traffic grid这一例子当中,. ?: S7 m+ ^7 `! B' c0 c
globals
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! z- w g3 b/ B" ~: w5 K4 H grid-x-inc ;; the amount of patches in between two roads in the x direction
- V1 n6 Q1 `, y4 n) T; L grid-y-inc ;; the amount of patches in between two roads in the y direction4 }. e! l7 r& `8 U
acceleration ;; the constant that controls how much a car speeds up or slows down by if
/ e. ]& ^4 X3 O9 _ ;; it is to accelerate or decelerate
0 s) f5 _ F3 P* y phase ;; keeps track of the phase) M9 J0 \$ f! \
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
+ ~# [8 z: N( h( \6 _ current-light ;; the currently selected light" Q& M L$ `: O1 N0 {4 t/ j3 Y3 ]
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;; patch agentsets8 s$ M9 B1 ~! a, p6 W( t* c+ z
intersections ;; agentset containing the patches that are intersections, o* { i# f; _& l8 m
roads ;; agentset containing the patches that are roads2 n! B) D! f9 G5 j1 e
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turtles-own, j! p, L; z2 X1 t0 I
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speed ;; the speed of the turtle! g: @1 F. N; y$ A, p0 W( q
up-car? ;; true if the turtle moves downwards and false if it moves to the right; r( Y1 w- l9 c" u' N0 i6 _/ i
wait-time ;; the amount of time since the last time a turtle has moved
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/ T& i7 W0 r7 j$ Gpatches-own. P& w, G4 B4 Q j& n
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6 w* C+ p [- p# z7 t intersection? ;; true if the patch is at the intersection of two roads0 i8 B0 J" F9 z, b4 [4 m. J
green-light-up? ;; true if the green light is above the intersection. otherwise, false.1 m0 ^6 i( l0 e$ I9 ?0 ^1 C. l
;; false for a non-intersection patches.
7 }; k' A3 r/ @2 ] my-row ;; the row of the intersection counting from the upper left corner of the
9 Y* j& O F& ^ ;; world. -1 for non-intersection patches.
# ?1 F: Q M( ^3 x' u6 r8 K my-column ;; the column of the intersection counting from the upper left corner of the7 K. H3 a6 `2 L8 k$ D
;; world. -1 for non-intersection patches.
1 `- r! W' `/ n z my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 p% Z$ q" w+ f9 e- v, p7 v1 D% L auto? ;; whether or not this intersection will switch automatically.' Y$ u( r8 v. P; _
;; false for non-intersection patches.) t" T, V4 k0 ^5 n
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;;;;;;;;;;;;;;;;;;;;;;
/ B: w+ C' K' S, ^4 [9 d, `;; Setup Procedures ;;
6 g: h8 o. U) f) k4 U+ `- R" Y;;;;;;;;;;;;;;;;;;;;;;$ S( _7 `( F0 O+ k( [& U
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;; Initialize the display by giving the global and patch variables initial values.
, P% l: u' ~2 b;; Create num-cars of turtles if there are enough road patches for one turtle to4 k4 X7 }: y4 x, c( g8 w
;; be created per road patch. Set up the plots.
1 F& E. a( H; eto setup B0 Y% M: d& c, {& K/ c
ca
3 l4 @; M( u1 P0 N/ J setup-globals0 E9 D! `4 j& H% |/ x( \$ l
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;; First we ask the patches to draw themselves and set up a few variables
0 t7 `) n2 y9 J7 j& s8 W setup-patches
" Y6 f* {" d2 U) ^1 M! `) I' c make-current one-of intersections
2 C) @7 Q7 D( [% z; a" U- a# y label-current) f9 C2 I5 k* f2 }0 Q# c6 E- |
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set-default-shape turtles "car"
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* W/ `/ Y' _% i& j. T1 f/ ` if (num-cars > count roads)) G) f9 [8 m$ O, p
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9 \7 b+ N/ S4 \& n, j, O user-message (word "There are too many cars for the amount of "
H, p1 i# ^# N5 p( ^5 d "road. Either increase the amount of roads "7 d$ l, U( b; i
"by increasing the GRID-SIZE-X or "" z% z# u& t: C
"GRID-SIZE-Y sliders, or decrease the "
0 f5 d& U& g3 i6 w& B "number of cars by lowering the NUMBER slider.\n"' m0 t+ x, p2 o0 R
"The setup has stopped.")
?! M3 v7 R6 C. w, ~) _$ H stop/ g7 m: |, V" t) R
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
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setup-cars) X7 q5 N B5 r% Y- l) d
set-car-color; q7 H: {% U! U w! F
record-data
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;; give the turtles an initial speed/ }4 M$ W5 S( q6 q7 J5 U7 D! c) E
ask turtles [ set-car-speed ]3 U) j# X: G" Y+ K: F: k# f( I
1 l0 B# [* f6 X- i0 N2 e reset-ticks8 F( @9 [! t1 D2 \1 x* r3 W3 {
end }* x) ~* a" X. F+ ]7 G" A/ V0 r0 q
! {5 d" b+ C4 i3 D; l0 n, V, };; Initialize the global variables to appropriate values# C& a: e' j; H y. o" m) I$ [5 [
to setup-globals
& j0 ^8 j/ w& G set current-light nobody ;; just for now, since there are no lights yet
6 k% P" @- R! y set phase 07 c! i, O1 K) D
set num-cars-stopped 0
; e/ W4 u, U2 V" H1 P4 Z set grid-x-inc world-width / grid-size-x
! \% H' L$ g! i, U' f) d$ v! R) C* P set grid-y-inc world-height / grid-size-y+ b' E2 o6 H3 T0 M' c" A3 b
6 t: r! `: H+ z0 }& z+ K; g3 t0 C6 L ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary& N5 \' s f2 o" u" u% K( [
set acceleration 0.099# g$ v& o* P! K1 J
end
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" V$ z ^( f; Q. `# d6 F;; Make the patches have appropriate colors, set up the roads and intersections agentsets,* ?7 W V. ?! ]6 d, s
;; and initialize the traffic lights to one setting
! x7 I0 ^, u$ p @- Vto setup-patches0 X$ ^. ?1 m9 s1 m2 B# D$ m1 p
;; initialize the patch-owned variables and color the patches to a base-color1 y) D/ {: [$ d! k1 y y( ]
ask patches
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set intersection? false- |3 o+ I( ]9 Z
set auto? false# m0 t: v; O0 s( V
set green-light-up? true; `+ E* z; Q. O# o) q2 c- x0 `2 R/ O
set my-row -1* i8 @5 {' v M
set my-column -1
5 ~. ?7 r1 c+ J0 \ set my-phase -1
" V0 N% b+ p2 R) q0 S set pcolor brown + 3
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1 P7 g8 ^ r. v: k ;; initialize the global variables that hold patch agentsets0 H& |8 a( ~: D/ b0 F- S. J
set roads patches with6 i1 Z5 t( L0 f1 o
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 ~6 C2 n! F& |' l" }7 j3 h (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 C k4 @- B7 I set intersections roads with
& H: r, q' d! k9 F1 D& _2 t [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and, ]$ l0 p1 N! U% w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)] J8 t U; `3 R7 D" K8 W5 }
& H& s) j/ A- h2 p# M" B1 m+ W ask roads [ set pcolor white ]
! }- \2 T7 j. X6 y1 q setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?; Q# p0 w& H' G2 ]3 \- ~6 X
set roads patches with, V) N7 K `7 e+ s
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, r# D* [3 _% ~* b9 t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 j/ H6 d0 D) \1 T% s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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