|
|
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。& _! L7 D8 D6 k
netlogo自带的social science--traffic grid这一例子当中,4 T( W' A, V0 x0 u0 q( m
globals
2 {3 |$ a2 m4 ]& ~' H3 e0 Z[
2 p9 s6 D& X$ N5 a$ X grid-x-inc ;; the amount of patches in between two roads in the x direction9 H& x( N$ ~7 u; r
grid-y-inc ;; the amount of patches in between two roads in the y direction
# I% |) {2 @0 I1 K' C& o acceleration ;; the constant that controls how much a car speeds up or slows down by if
% G; ^; D7 K3 X ;; it is to accelerate or decelerate7 l/ l% i( [8 V$ @. U
phase ;; keeps track of the phase5 v/ q5 k% p" @# ~/ T
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
8 d' O6 \' C9 T6 J- T d current-light ;; the currently selected light0 ^5 a) K6 |. t1 w. v* Y
( e; l( Z$ u! V+ W1 r ;; patch agentsets
: w. F9 C) T% k. z. o- F/ K: L5 X intersections ;; agentset containing the patches that are intersections
; c, h4 p8 \& {8 v9 B roads ;; agentset containing the patches that are roads- k- S) v* f/ `8 b q2 c
]9 \1 V* D7 j1 R7 p/ r" Y1 l
) I- t( U, N* a) P9 O6 Lturtles-own" |2 _9 [+ v* l. C/ p4 u, d4 V6 H
[
1 G6 T4 ]. \6 {" m speed ;; the speed of the turtle' J2 n) y! D H# b4 H
up-car? ;; true if the turtle moves downwards and false if it moves to the right4 b/ G. P4 z7 e3 K
wait-time ;; the amount of time since the last time a turtle has moved
) U2 y0 v" ?6 n- c8 {], l' @: b- ^4 b8 J m- G
5 t9 M W) G! [patches-own
/ g4 [) d/ j4 X' Q- r1 ][
# [0 y& f- p4 V, j5 n: h; @ intersection? ;; true if the patch is at the intersection of two roads1 y m' {- m7 v' X6 b6 j5 N/ @
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
2 f( c* g' W$ J* ^7 F ;; false for a non-intersection patches.2 V3 Q, h1 G" t8 P+ Z3 y
my-row ;; the row of the intersection counting from the upper left corner of the- S1 }6 z0 N1 s/ J
;; world. -1 for non-intersection patches.
; U+ C3 J. o: m# ^1 W+ Y. F- _) F my-column ;; the column of the intersection counting from the upper left corner of the
0 }3 ^5 P2 `# t ;; world. -1 for non-intersection patches.+ c! w7 \; X* ?" D! J
my-phase ;; the phase for the intersection. -1 for non-intersection patches.) S; h* j% A/ o) }+ u/ {
auto? ;; whether or not this intersection will switch automatically.
, g6 Z+ t) x. Z0 M# P. L% F ;; false for non-intersection patches.' z' [+ @( _) Y& W
]2 U7 n5 P9 e# m$ x2 O8 @
) y) {% S3 n7 z9 p; y, I& h8 P
7 P2 s5 S* _8 R" z" S7 l;;;;;;;;;;;;;;;;;;;;;;& V) \5 [* `: t6 h
;; Setup Procedures ;;
0 a) S1 \' _9 M' n;;;;;;;;;;;;;;;;;;;;;;
% B8 r/ I9 C- }$ i0 Q" X/ b5 C# g. t/ g# t7 |( E
;; Initialize the display by giving the global and patch variables initial values.0 A/ D% @, F$ h+ d" ?" J4 g# y
;; Create num-cars of turtles if there are enough road patches for one turtle to
: W) J% ]9 o v4 D) s/ M# N;; be created per road patch. Set up the plots.3 m# v" w6 E! J$ U( \
to setup Q9 R9 Z, Q, O5 u7 K. n
ca t' q1 q- h4 u2 N3 p8 d+ K' k
setup-globals
) ~- w3 e9 _" B5 |! C- v! A9 j l+ q3 I; F5 r, w, ]' Y7 o
;; First we ask the patches to draw themselves and set up a few variables4 Z7 _" s0 X' @% G, G& j+ ]/ q( [" ^
setup-patches
' t) {3 g" E7 u0 Q" M) U; L make-current one-of intersections) V6 T- {, e2 w) m) B& U- Z' W3 Q2 @6 D
label-current2 V: m/ h. Z7 v0 K
: ?# f) r5 N+ ~. R) K- t set-default-shape turtles "car"9 G8 j2 N# P5 U8 B2 p7 f" z3 Z$ k
7 k/ k% `, y4 W0 m( D
if (num-cars > count roads)
' p l( f0 u3 Y: t9 O [
# E9 r) ~* C6 E/ E! U% Z user-message (word "There are too many cars for the amount of "
$ O3 o: }/ G p1 Q0 ?3 z "road. Either increase the amount of roads "
8 l: [; P- F. R; O "by increasing the GRID-SIZE-X or "
1 R1 [3 c! y2 H6 S "GRID-SIZE-Y sliders, or decrease the "
- B, \( ^4 b" e& \+ g) S; {0 \ "number of cars by lowering the NUMBER slider.\n"5 E R$ l! `' p! S1 f" D3 C
"The setup has stopped.")5 T2 R R& Y( {1 N& q
stop5 X# Y, ~: C0 j+ ^; r% K X# f2 ^
]* K! b( U" l4 I$ r
r' q; B# r7 q( k9 z5 W* d
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
2 q2 x5 b8 H* \7 J2 R' D$ e ` crt num-cars
0 B# Y* }. e" p4 O6 X [% w1 Y) L$ I4 k! S* R d. x
setup-cars
% S- o; e7 j; R5 ^3 W$ v set-car-color
1 R/ l* Y6 ~% a9 F record-data5 g: A2 M# b) t# D' ]9 F( U
]4 M, I, p- D7 \3 q/ }
% e/ S- g& b- u( z( K8 M
;; give the turtles an initial speed
' Y5 k9 {1 j$ t# n ask turtles [ set-car-speed ]
& E* J1 I0 q. H& n, L
$ J7 ^8 p% D; O9 U4 ~: V0 B reset-ticks7 g# ^3 I6 g q' q6 g! w/ N; k( ?
end2 A+ ]) t" X) P
& X- F& ? X0 ~6 h) c; P# \;; Initialize the global variables to appropriate values
1 y" I6 R3 k* pto setup-globals
+ r2 c3 U" j3 S4 P7 x4 i9 }9 i$ M" y set current-light nobody ;; just for now, since there are no lights yet
( \: s# b6 |3 E9 R! R set phase 0
8 z; g9 w+ G7 k7 h" M) j" U set num-cars-stopped 0
( R5 `" l. X2 J. ]$ D+ q3 u. ~ set grid-x-inc world-width / grid-size-x( D/ y6 w: |; R U( v- T
set grid-y-inc world-height / grid-size-y
6 c: E- @9 l3 t& m1 J7 D7 [$ \: t' K3 I' \
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary6 D' y2 a. x) e O4 ^& g1 C y! @
set acceleration 0.099
$ }5 q+ L0 |1 [9 eend
% @/ w% S* x b+ l
' _9 B- s& b8 K9 R$ y! B3 f) j;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
, Q. v |; j& y;; and initialize the traffic lights to one setting0 i) p& z! _& z2 j- O
to setup-patches
, x' f. N& {5 M+ \3 ?- \9 D3 c ;; initialize the patch-owned variables and color the patches to a base-color" e4 J ~' }. Z: ^5 m6 U0 S% `. S
ask patches; u5 h% N# t J& @
[
8 t2 b8 D, C6 \( G set intersection? false
7 h1 J1 y r5 C- |% E. U set auto? false
! w% l8 v3 _) \8 ` set green-light-up? true
( ^8 B7 n4 X* w1 r9 S set my-row -1+ ]3 k9 w9 d9 \3 g, }5 Y7 x0 p
set my-column -1
" c! x0 i( Z( b set my-phase -1
3 ^5 ]& f2 K+ ?& k set pcolor brown + 3
: c/ W" R* E+ h" t/ a ]7 p! K* Z( x' b/ l/ }* R
6 h1 q6 w2 }+ W* w* [
;; initialize the global variables that hold patch agentsets
0 p. [3 ^2 c3 J) ^' p set roads patches with
$ ]" C( ?. o5 Z& X! e: t6 B: J5 z, o [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
" B: A* u& T+ m2 A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ w8 p' R$ {9 \; J7 H g6 [ set intersections roads with2 I4 L) w( z5 a% G
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and- R& u" z6 L1 N+ P" P& D" s
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
: E% [/ ^) F% q5 l; O0 H, H: N/ \. S
# O! w5 T- E5 O! X1 v ask roads [ set pcolor white ]2 C( D3 J' _) o9 |0 w$ X' ]. @
setup-intersections
" @" f$ @7 Z9 e: ^/ wend! c6 R) H2 ^1 V6 @! |1 K3 q! J. S
其中定义道路的句子,如下所示,是什么意思啊?% A$ p* V. |/ D9 V: ~9 c* ~$ I. C
set roads patches with, X0 R9 J! c5 |% s2 T1 t i* a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
6 b" l, D+ i5 T4 R( e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ s% r; v8 a6 c' K! L1 t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? |
|