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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 o1 k) ~! ]7 d7 v' k; ?
netlogo自带的social science--traffic grid这一例子当中,6 o) j2 c( [0 D8 V( c, B
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction% d F% L- W- o) b6 H* S
grid-y-inc ;; the amount of patches in between two roads in the y direction) w: G; {+ _ @
acceleration ;; the constant that controls how much a car speeds up or slows down by if
, _9 F1 x4 Q. O& w' M$ k0 H' Q) } ;; it is to accelerate or decelerate8 W- V7 d. \, \ h* W( w
phase ;; keeps track of the phase
7 o% h& L* r4 W4 D, k: |( }6 k num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure9 ]0 |3 |7 T0 I1 X4 f. \0 a
current-light ;; the currently selected light! q; T" C- D% {* _3 g; `
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;; patch agentsets
" U) \* v8 t! [% H: _9 @ intersections ;; agentset containing the patches that are intersections
9 B3 F: Y1 F$ G$ I. k roads ;; agentset containing the patches that are roads
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. O6 V; ~9 C) R4 _turtles-own; _( h2 `: U( ~: R& T* |+ b
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speed ;; the speed of the turtle
( y) w5 w. n7 c: [7 x8 o8 |, S up-car? ;; true if the turtle moves downwards and false if it moves to the right! V0 K) y, E3 X
wait-time ;; the amount of time since the last time a turtle has moved
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1 E1 \, `2 E3 G/ e7 opatches-own2 ]. D: e( u4 \1 e) T, D% x" e
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intersection? ;; true if the patch is at the intersection of two roads
& B& I: E) |' p* P# R- A! X& e green-light-up? ;; true if the green light is above the intersection. otherwise, false.; g% v# m" X2 z9 ~# |2 h5 y
;; false for a non-intersection patches.
+ P$ z1 i$ A L8 A# P my-row ;; the row of the intersection counting from the upper left corner of the
4 }" |- A" h, Z2 ~' o' t, t! O' W6 i" @ ;; world. -1 for non-intersection patches.
$ I$ F$ [' p" O' e6 w7 Q( ^# |) d my-column ;; the column of the intersection counting from the upper left corner of the
# D; k) m5 X Q4 K: h9 r ;; world. -1 for non-intersection patches.0 W- B q1 ?) F! |8 }# Y1 S
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
1 v [7 l' S x- F- N+ g auto? ;; whether or not this intersection will switch automatically.' A* a: D5 Z8 o. j. L4 ?
;; false for non-intersection patches." ~ P+ [$ k% }) p9 \
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;;;;;;;;;;;;;;;;;;;;;;9 ]# U- w0 D7 ]2 J1 k8 j% }! A, s: E
;; Setup Procedures ;;# s' j. w/ p3 j( W' k* f7 s' ^! S
;;;;;;;;;;;;;;;;;;;;;;3 ^( ] ~; A/ b* l$ m: J# w3 s
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;; Initialize the display by giving the global and patch variables initial values.
) x' f7 }4 C2 E5 b B) A;; Create num-cars of turtles if there are enough road patches for one turtle to
, P; I" f0 m, {. _) q9 I* W;; be created per road patch. Set up the plots.# I+ [4 b" R' h
to setup
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6 S. Y1 `' D. D6 ? setup-globals
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5 i0 K+ _" U8 r- [- q# V$ Y ;; First we ask the patches to draw themselves and set up a few variables; _2 y; J5 _4 l/ p) n7 I$ A
setup-patches
' E0 W, i; O# m+ K! F2 y make-current one-of intersections
( o6 \5 Y0 a4 Q" v0 B% U4 v label-current
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set-default-shape turtles "car"
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. s, L3 ~* f6 D8 j: u if (num-cars > count roads)
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, u1 p. G- B7 w/ j+ c user-message (word "There are too many cars for the amount of "
8 M& _3 L; P8 P+ \' B "road. Either increase the amount of roads "/ n! A6 r( p3 U, G# g& S6 J+ K1 A, Q C
"by increasing the GRID-SIZE-X or "
9 j% M5 |! h E7 h2 @/ q "GRID-SIZE-Y sliders, or decrease the "
, c+ ?9 O8 C+ c% ?# @, b "number of cars by lowering the NUMBER slider.\n"
2 G7 P) W+ T( i, v "The setup has stopped.")
! r: @. r0 |, y( q8 ~4 _ stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color6 T* w9 f7 Z% S
crt num-cars3 m% E! E3 y; n9 H1 f
[
- I8 p2 j u0 R6 y setup-cars% Q3 U/ R. w5 }, N
set-car-color
5 |2 G" \# n, ^* C9 o6 j7 ` record-data
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# w2 m" b9 x b& U ;; give the turtles an initial speed& i- e6 [3 m+ g
ask turtles [ set-car-speed ]. C) z/ W5 ^8 }! m( K. W1 }7 p
: f% z5 |" L3 U/ \* I reset-ticks3 L& Z. h7 {3 `0 M$ @+ }; X+ Y
end
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/ k1 Q. w6 _# I;; Initialize the global variables to appropriate values0 T( I( M M% A0 Z, Z! {9 m
to setup-globals
6 i9 x$ D7 `- B6 O$ y, B set current-light nobody ;; just for now, since there are no lights yet
# [/ O) }/ H, G; f6 ?& e$ n set phase 0, P: ~$ O, Z& h" a0 E
set num-cars-stopped 09 }$ j$ i8 E: F4 y
set grid-x-inc world-width / grid-size-x4 [3 ]% N, N/ n( J7 s
set grid-y-inc world-height / grid-size-y
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7 a$ u/ \, e9 `) n ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary1 t# c1 `7 C5 ?. M! C* }
set acceleration 0.099
$ z- r% B. W4 L8 ^end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
: {( n( C* q F, l J' v;; and initialize the traffic lights to one setting$ l' f. C7 f% z) L% y$ j4 C
to setup-patches
- Z6 A: k% k$ P! M ;; initialize the patch-owned variables and color the patches to a base-color
2 P" P$ w$ ~$ k e( P1 i1 ~ ask patches7 T# {: K5 H6 A! Z+ L4 `
[
0 Q6 D7 \6 v" M5 ?4 f( E0 u4 v$ s set intersection? false
1 B; O# M# S7 k; V0 o! @8 Y7 F set auto? false
4 e; A) _, p' b l set green-light-up? true
9 [8 U# [4 C- T/ g+ Q set my-row -1
% v: ]3 ?* \- w# V2 P7 L! v' d! | set my-column -1
. E. |9 I$ m' q! H set my-phase -1- X- ]8 B% d, A) o# q
set pcolor brown + 3
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; J o; G, Y6 H6 k ;; initialize the global variables that hold patch agentsets
8 s, j, W( R2 E, R5 _ set roads patches with9 O7 r# U! G; R) t
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or( d# p* l8 A" S( K' M# h
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! s. h4 L% F1 _$ M c8 n" a' D set intersections roads with( ~$ O. g/ c9 t, c! W3 h
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
$ A4 _+ a$ k* x" l& i (floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ Y V7 \( s& b: N3 B& w. t
! t- ~: b- ]4 C* z ask roads [ set pcolor white ]
9 H6 p7 Q) R. s2 x setup-intersections9 X8 T( I& N. _! Q' O
end) n. F$ F6 O# e* W1 f
其中定义道路的句子,如下所示,是什么意思啊?
2 l8 \# A! d( d5 P$ E: v, | set roads patches with3 S: h! P. o6 g$ Y+ j. Y1 a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% r8 s, t- O* `8 J2 J4 f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]. _% Z" j; k2 w. L/ l; 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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