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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。
3 I# m' [3 s) I5 E3 _3 Ynetlogo自带的social science--traffic grid这一例子当中,
- f7 u; ^. O% b/ _7 |globals( h' \+ K+ c; f2 @
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/ N' g# L; y3 @" W- _ grid-x-inc ;; the amount of patches in between two roads in the x direction
7 L. \6 _5 {! m5 x7 d# j' u+ u grid-y-inc ;; the amount of patches in between two roads in the y direction
" ?3 ]0 p' t5 Y; S A acceleration ;; the constant that controls how much a car speeds up or slows down by if% J' b% g1 @# ?
;; it is to accelerate or decelerate
6 h. {$ M3 c2 W phase ;; keeps track of the phase
~. w& Q; J- \% n! r v/ H num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
. {& g' C: ]+ b current-light ;; the currently selected light
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;; patch agentsets- l8 d5 A& P n6 o G+ h' F
intersections ;; agentset containing the patches that are intersections6 W* T( U% {/ V! g9 l7 `
roads ;; agentset containing the patches that are roads! {: L$ ^, u$ f; L) s$ V; ^
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turtles-own, u% m& D# i5 ?
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speed ;; the speed of the turtle3 d, P; s' C0 z
up-car? ;; true if the turtle moves downwards and false if it moves to the right
: E7 K; d& r6 @/ h* t wait-time ;; the amount of time since the last time a turtle has moved$ W+ i/ a; `, y, L( h
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2 r1 P, Z* { ]8 |" i3 a( r( _patches-own7 f5 A0 L; m! o
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s/ u' E, v/ M, U+ G9 H) W* y intersection? ;; true if the patch is at the intersection of two roads
* P2 `" b6 P# Q+ m$ D green-light-up? ;; true if the green light is above the intersection. otherwise, false.4 J7 M: r. p- m5 H2 B0 G
;; false for a non-intersection patches.$ t7 p2 L8 H8 H+ E% ?8 E$ q7 ]
my-row ;; the row of the intersection counting from the upper left corner of the
. O6 ?# q2 z* G0 G# {, |$ d ;; world. -1 for non-intersection patches.
4 N8 f6 @3 [% Z3 Z# x. E( A; }+ t my-column ;; the column of the intersection counting from the upper left corner of the
`0 e5 e. {0 h( S ;; world. -1 for non-intersection patches.; V1 H. f2 L" a* m2 p7 l2 o4 K* i
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; O3 W& w2 T; T auto? ;; whether or not this intersection will switch automatically.7 H7 r e R/ s1 |( |
;; false for non-intersection patches.! Z: M* q- ^5 K
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9 n" J- J+ K" l; b4 O: r;;;;;;;;;;;;;;;;;;;;;;
! `3 j& C2 g- j2 P% x& o1 M% O;; Setup Procedures ;;
$ {& V t# X0 c0 u* V% a;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.6 g- h S" c8 V* |
;; Create num-cars of turtles if there are enough road patches for one turtle to
4 X, u+ r* L* ^& z; {;; be created per road patch. Set up the plots.7 B$ O- S' \* U! C/ K
to setup. g% G7 j& x6 `% h( v3 y- }
ca
" L& i( |% r7 |. t) j3 ` setup-globals
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4 p& L J; j" n8 W9 Q: @* l/ i ;; First we ask the patches to draw themselves and set up a few variables
3 J; i4 J& Z% q" U: j setup-patches
0 e6 v9 J# D+ Z, c. V( ~& F' ]! P make-current one-of intersections( P/ v; Y- m6 z6 o* C3 P
label-current
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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 ": O0 P s- ~1 ^. l! X/ M6 {1 R
"road. Either increase the amount of roads "
6 w! b: a h) @# I; P "by increasing the GRID-SIZE-X or "1 Z0 i/ o. ^4 K9 O& a4 w3 a/ ~
"GRID-SIZE-Y sliders, or decrease the "
& I5 H& M) I, i M5 [. i4 y3 Z$ d "number of cars by lowering the NUMBER slider.\n"# }- V9 ~9 @/ t3 V- p2 ?
"The setup has stopped.")( L) c; i/ a3 g* T
stop
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Z4 S8 ~' }& f* S' K v0 q4 a ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
. r3 _+ N! v/ A6 X7 i4 t crt num-cars
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3 a4 W( H( D F4 g6 l$ G setup-cars
+ V* S \. a- D set-car-color; _! ~" j/ }7 j+ v4 b. V# C
record-data* ^( e" }7 k! N+ V8 f9 d% A, }
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;; give the turtles an initial speed. O+ Y5 R% W# n9 I
ask turtles [ set-car-speed ]
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7 V* K$ [4 _' F4 E) K) ^ reset-ticks
) Z2 x% C, I* n. \end y ?* V$ j# x3 [8 F) ?8 N$ G
c4 e. i& B3 C9 n; H6 Z. E;; Initialize the global variables to appropriate values
' E! d$ U5 c: }0 k' Kto setup-globals
. S4 _/ G% P+ ^- V set current-light nobody ;; just for now, since there are no lights yet: X5 b5 S6 I0 P5 |9 R0 `9 G
set phase 0' _- ^' A- f/ e7 K
set num-cars-stopped 0
/ M: ^. R8 f! ~3 S# A7 l* @( B set grid-x-inc world-width / grid-size-x
! ~$ T8 w! N( ^1 t6 l/ [ set grid-y-inc world-height / grid-size-y$ ?9 @; O0 a! e) _( N5 c6 @
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary/ ^3 d, h. l" l+ O5 H# i
set acceleration 0.099/ {1 ?: n2 c8 r! p3 }
end) U. _9 |( l: z
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
5 @7 E% ^$ e& C. W/ K$ v;; and initialize the traffic lights to one setting
* a" D: x# Y; Q/ ?3 R5 T. bto setup-patches
/ X" Z1 a5 _# d W+ e0 i1 { G7 P ;; initialize the patch-owned variables and color the patches to a base-color1 p4 y& ]; x% v8 O# ?/ B: q; c
ask patches
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5 d0 p& S/ S. P9 \3 r& k set intersection? false! G0 S( B% l: j
set auto? false
, \. [6 x% W$ _5 h2 I set green-light-up? true3 B, m0 i9 Z* g& j' v6 b* H6 C
set my-row -1
. M' }1 _: E5 C2 a. W% ? set my-column -1
$ d! i5 u& o$ O6 u- K; h5 a set my-phase -13 H o1 U6 f/ P
set pcolor brown + 3/ j# `6 I' L* V/ f* i& s9 K& j
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% ^" K3 M: J2 j6 A l3 ~& T ;; initialize the global variables that hold patch agentsets# g9 q' d( S5 d3 [
set roads patches with
* N3 _8 z% g+ E' u4 [* }0 N6 x [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. l' Q8 Z, D- ]9 V9 g
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& t" U$ {7 t$ a set intersections roads with
" b' V! _" J2 x& ?; ~: z9 g @ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and, ~8 U E, v0 t5 _. }5 n/ C9 j
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# L! N" h, ~4 m' G/ `6 i6 k- v7 X
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ask roads [ set pcolor white ]( k( C4 s* V# l' h, `6 D2 _( g
setup-intersections/ e9 r8 U# L M
end
, u' H2 x {% i1 F其中定义道路的句子,如下所示,是什么意思啊?
& ]* _6 E0 O/ l5 s: I9 | set roads patches with
& U" ^$ Q- B D0 ~+ m* m [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
9 v" N8 U* k/ z1 \( y* v5 f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# z1 X- m5 d& n" l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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