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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。
; F9 u) X [: `; Snetlogo自带的social science--traffic grid这一例子当中,3 i1 f3 I! h6 C: [5 k7 C
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction! |" T* x J/ Q c' c/ b, i! U' o
grid-y-inc ;; the amount of patches in between two roads in the y direction
1 x, \. z8 A/ o& h. r' L% x acceleration ;; the constant that controls how much a car speeds up or slows down by if
5 Q6 j1 ]. \2 H) f/ k+ E3 b q7 r; ? ;; it is to accelerate or decelerate, g2 }& N8 R3 E K5 }
phase ;; keeps track of the phase
0 j! A: }. {0 P- e num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
- \! t4 W! J+ E! i) r current-light ;; the currently selected light0 m- K% u6 G9 a: x% `+ U- p- w
0 X9 ]) F- N4 N( k0 O0 u- W/ | ;; patch agentsets$ R8 O; E5 f8 w$ \6 m
intersections ;; agentset containing the patches that are intersections( Y$ g O7 o3 V! ^- g
roads ;; agentset containing the patches that are roads
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+ y4 G) w# m* x% }$ |5 k' fturtles-own' j2 L& L, H: W$ f, P% W
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speed ;; the speed of the turtle
; ], }0 s! h! I7 w) h up-car? ;; true if the turtle moves downwards and false if it moves to the right) \9 J& e* y1 x$ m# l
wait-time ;; the amount of time since the last time a turtle has moved7 s+ m- Y9 @+ U' F" g1 ^; M( E# K
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patches-own# Y7 x1 D1 z, n9 j. m8 V/ G
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8 B. }& }/ _# ~' O6 O intersection? ;; true if the patch is at the intersection of two roads
" c9 o: O5 t- M; c: b( q green-light-up? ;; true if the green light is above the intersection. otherwise, false., z% E3 p* }5 T2 g( p
;; false for a non-intersection patches.) E$ _, f2 l; K; C
my-row ;; the row of the intersection counting from the upper left corner of the. p! N3 o" Q8 n' a1 ?( b) s" [( ]
;; world. -1 for non-intersection patches.3 {( L$ b" W; d: m5 r
my-column ;; the column of the intersection counting from the upper left corner of the
1 |# r0 G- y2 y) V4 Q ;; world. -1 for non-intersection patches.: p$ b) W. }) u8 j1 V* U
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
$ U! w' V; k G, E auto? ;; whether or not this intersection will switch automatically.
( O1 x' T2 q8 w" Y# s9 j* i ;; false for non-intersection patches.3 h. d& y& S9 `( D# k) |9 V
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;;;;;;;;;;;;;;;;;;;;;;
- g& z$ \) ]. s( E;; Setup Procedures ;;" [, S R$ d9 |: w
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;; Initialize the display by giving the global and patch variables initial values.
4 X/ B4 w7 n, j! p! o( l; h1 F;; Create num-cars of turtles if there are enough road patches for one turtle to- E/ O0 w) u- m+ ^+ p7 J# ?) i1 Y
;; be created per road patch. Set up the plots.
+ d& y* u# W V& P# v5 R+ Tto setup+ \% B. n0 e- f
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setup-globals
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8 ?! s9 H: e% q0 ^, b ;; First we ask the patches to draw themselves and set up a few variables; ^6 }# v; d7 y5 M7 _
setup-patches5 {- e. b" z1 D' s8 O, y# V
make-current one-of intersections' a+ ~0 Y1 V1 A) C
label-current$ @3 u7 [8 Z1 y% a8 a, S
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set-default-shape turtles "car". X% N+ O) ]- @7 R. Y8 v
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if (num-cars > count roads)* f- ^& L* L! s, ^. F
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user-message (word "There are too many cars for the amount of "
5 _+ R- i `; a3 h. w7 P! T. l "road. Either increase the amount of roads "9 [ l! v* i7 w/ k2 V# z4 u2 [% I
"by increasing the GRID-SIZE-X or "2 ~0 H' M# J( b& g
"GRID-SIZE-Y sliders, or decrease the "1 m9 o7 B+ |1 `% y4 F- X
"number of cars by lowering the NUMBER slider.\n"
! d# z0 R/ W# _7 k7 X "The setup has stopped.")
) @% W( ]) Y6 e0 Q stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color0 T; X" @* A# O' ~0 s
crt num-cars4 J! p; \. z9 }0 s. M0 P: o4 F' O
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set-car-color
$ q3 ^* a8 F) s0 ^5 X* f record-data; ?; c5 \- @% \: E- J+ Y1 l
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;; give the turtles an initial speed
$ Z' P# H# S# d2 Q, }9 D. f ask turtles [ set-car-speed ]
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$ O; o0 U1 q( V& X" y/ @! H reset-ticks j' } P; C# p. c6 j q: {
end
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; }: V% |4 @: m) U8 V. r8 d;; Initialize the global variables to appropriate values4 W; D! O8 d9 u# ~/ C+ f9 x" }
to setup-globals
8 h U9 |* q4 }8 W' Z set current-light nobody ;; just for now, since there are no lights yet# E, u! K! }" J* [; R2 d K
set phase 0% b/ v& E* v' C* ?
set num-cars-stopped 0
3 D7 U O3 \1 a: b: M set grid-x-inc world-width / grid-size-x. y7 f& s: D# j; ]2 ^: J
set grid-y-inc world-height / grid-size-y: i. M- y7 j, }0 W7 [0 m
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
6 d7 a! K6 e2 p6 Z$ d9 ^ set acceleration 0.099# z8 h( k3 o. b1 [; X0 H
end) }3 {0 R, g$ W q
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,; f3 @0 \9 n; }
;; and initialize the traffic lights to one setting
" L) e4 B3 F2 Y# s3 d; f W! @to setup-patches
1 W1 {9 g9 b* B% z$ t# t ;; initialize the patch-owned variables and color the patches to a base-color
# N+ J" i+ `' B% g6 r0 g ask patches
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4 L- t v4 d' k5 q6 C set intersection? false9 [4 _3 @5 U* _) @8 N2 J: X
set auto? false/ \8 j( U8 `2 h+ D
set green-light-up? true4 N2 Q5 F3 g, n5 G( l
set my-row -10 A! W- @, o$ G7 G8 k, @4 D
set my-column -1 r& g# R8 m9 ]* v: q& Z
set my-phase -1
" z) w; T4 ?2 n E# H" x set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
2 ` `+ q, F6 ] set roads patches with3 b; i: P' J* q6 @
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
! h& u4 B" `' ]& d5 b+ F8 _1 Q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 @' N& A7 c6 q- G
set intersections roads with
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% t& A, D3 T* Q8 z( v/ N7 Q) K (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( e) L/ T# H. Y0 m7 E
8 U; y; i+ G0 h' P" O+ m+ F" n ask roads [ set pcolor white ]; I8 z& I, d9 q# [8 K3 c
setup-intersections
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3 l' Q9 M. T8 A( ~% E) d其中定义道路的句子,如下所示,是什么意思啊?
+ \* e# m- H# r2 O3 P2 M& h set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. Y4 o1 i5 Q% @: V% e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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