|
|
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。
/ _0 m" ]( R3 P2 rnetlogo自带的social science--traffic grid这一例子当中,
6 ?0 a& v+ g7 _; x0 T& [9 ]globals7 s8 l, b6 J" }
[/ b; m2 b# n* [ b9 t5 [
grid-x-inc ;; the amount of patches in between two roads in the x direction2 \) \9 P" s# X# r' }, T/ \3 |6 x
grid-y-inc ;; the amount of patches in between two roads in the y direction3 v7 R8 B, w( W
acceleration ;; the constant that controls how much a car speeds up or slows down by if
, |6 O( M3 ^' m ;; it is to accelerate or decelerate( j0 U4 r: K6 d2 L8 i' }
phase ;; keeps track of the phase
3 N! N3 Y: L! k num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure9 m' Q K5 f+ X% h
current-light ;; the currently selected light
; |) b; m/ s% {0 I$ l z1 `" o: o4 k: k! x
;; patch agentsets* S2 @) ]" |! u/ U9 E, `
intersections ;; agentset containing the patches that are intersections* W( j8 K4 f) v% a8 V" M5 z
roads ;; agentset containing the patches that are roads- N4 J& P; V5 M
]
0 W# R$ K: v% [" d# N( V
1 ?3 x% n5 s: B9 F; lturtles-own: b# k- ^+ e9 {
[: C5 z6 n1 F+ I
speed ;; the speed of the turtle0 d& t$ |: k4 D: J/ j( r
up-car? ;; true if the turtle moves downwards and false if it moves to the right" d! N+ @/ L# c9 d% P. F7 q; `. Y6 W
wait-time ;; the amount of time since the last time a turtle has moved$ T& b* L( g+ X9 t2 n! O
]7 j' h9 h- R/ Y' h! A" S! W" Z
, ^* k. E& T8 O3 Y
patches-own0 ?! ~& ]6 ^# f6 r) _' f6 C
[
4 F' b9 z8 A0 x3 [3 T! K intersection? ;; true if the patch is at the intersection of two roads
2 U% Q6 z* ], p j green-light-up? ;; true if the green light is above the intersection. otherwise, false.
4 ^; Z _8 o+ @) A0 c ;; false for a non-intersection patches.
( G" y+ `, K& `8 Q6 a& `6 e# D my-row ;; the row of the intersection counting from the upper left corner of the
$ k0 n) i+ X1 Y4 C7 b( S: K/ B ;; world. -1 for non-intersection patches.
2 f t+ b% ^$ A9 G my-column ;; the column of the intersection counting from the upper left corner of the: w5 w r: Z0 j. Q/ P8 l
;; world. -1 for non-intersection patches.
, R1 N5 a2 @' ~- [ my-phase ;; the phase for the intersection. -1 for non-intersection patches.
' e2 Z. R9 R) A auto? ;; whether or not this intersection will switch automatically.% s! c8 `" p: B2 E6 r: g6 C& X
;; false for non-intersection patches.0 `+ t2 p! Z2 \, K0 h
]; ?( [* ]5 d$ @5 D) K( ?2 H
/ I3 r% C- J2 L2 B; \
% z1 a) B! V& g( s# B;;;;;;;;;;;;;;;;;;;;;;" X$ ? B4 `$ P9 a) R
;; Setup Procedures ;;
' h4 I7 c& s N- z& r- E4 ];;;;;;;;;;;;;;;;;;;;;;
( C, }' j3 @ [+ B* _& m8 U4 m) ]" I7 O, z
;; Initialize the display by giving the global and patch variables initial values.
; C6 }( _( i/ W4 Q* q' K+ k" V;; Create num-cars of turtles if there are enough road patches for one turtle to
' r6 ^. M! @8 p5 F6 D( L3 C9 \ Y;; be created per road patch. Set up the plots.6 T& ^! z, [ T2 b7 R
to setup
5 q; n% v$ P3 t, Q( A ca( H" W3 J8 G- u4 F/ F$ @, ]
setup-globals3 s+ e, F3 q. L/ R% r
( y$ r0 k t+ {7 p; ^: _2 \
;; First we ask the patches to draw themselves and set up a few variables
: M0 s A7 m2 j% S0 w Q) s1 b setup-patches9 x" } E4 j: B8 E( S' c+ s2 q) y
make-current one-of intersections
, i5 j% c5 A$ f- C label-current* b8 C' h3 X! y* k( m
, I1 o, `; `6 a: e) f
set-default-shape turtles "car"
; K/ A" A9 q5 R3 P) N7 C- t; |9 G( z1 G" o' z( M7 B3 |
if (num-cars > count roads)
# t5 l+ L7 M# i8 x Q [, U8 ]" i0 ?+ T
user-message (word "There are too many cars for the amount of "# l: m& R# V0 b" b. b* z* H4 l0 I
"road. Either increase the amount of roads "3 X, a! O9 |. O3 m& P3 f$ z1 t5 @
"by increasing the GRID-SIZE-X or "& V" M, u" z0 j. x& A
"GRID-SIZE-Y sliders, or decrease the "" D# Z& k8 e |5 t
"number of cars by lowering the NUMBER slider.\n"8 B: |- \! p4 ]" R6 S% ~+ |- Z
"The setup has stopped.")
5 z# E a4 W* c7 u stop
8 ?; m3 ^. i( O( {# [0 Y ]! t7 o! X) `$ O: T8 A& n1 ~6 o
" _0 _5 o/ Q" y) ?4 h ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color) o* {+ t% Y& j
crt num-cars! V7 N/ d1 A' M; I5 q7 M
[" i* b E$ I4 e/ `( R, c
setup-cars8 e5 h9 m# l" Q0 S5 {) J- U- `
set-car-color r& X3 T: a+ i1 F6 H" d) ~
record-data0 l8 G' ]) @) k Q9 ^) C2 ^7 X
]
/ ^+ J# u- ]! M" D# L$ y" \8 V* ^' L: w. y4 G& b
;; give the turtles an initial speed
6 V1 L! O2 U) L0 m, } ask turtles [ set-car-speed ]
$ t* D. u, s/ X1 g4 i) v; x- B( [! V/ n+ d5 e3 p" d
reset-ticks
' i8 P3 Z/ X; W* A, h) Rend
; M# v/ m# }+ I. d* r" q/ a; F. z
2 L! b- t1 L6 |;; Initialize the global variables to appropriate values
% X) |9 T! H9 ~" H' nto setup-globals
. A, f7 v: j' h set current-light nobody ;; just for now, since there are no lights yet
x3 v% P2 U# L$ e) \ set phase 06 N4 v. J$ J# Z. w! `) y
set num-cars-stopped 0
# ^6 `, g: p2 _2 J; {9 A) E set grid-x-inc world-width / grid-size-x( O# a8 [* q, W6 N( j3 H
set grid-y-inc world-height / grid-size-y
" v# l4 c" g) ~; I; s1 t: s) [1 j
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary! q- T1 I. N4 h3 |( j0 |8 {0 `0 m6 y
set acceleration 0.099
. R: [' J. {( F) Kend9 V# o/ Z9 X. _2 _* X3 @( Q3 G
" p! s1 }! C7 E/ L; Z5 V
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
; {: {( E8 C1 M& L# n- a, c;; and initialize the traffic lights to one setting
$ \, X# ~5 W# S/ l6 U5 ]9 Q, Z5 \to setup-patches
8 q# J) _2 a; c% n ;; initialize the patch-owned variables and color the patches to a base-color4 |: o7 i! l% l4 f1 _
ask patches2 Y+ o, W& q* [, \2 S+ s& B, d
[5 q+ m& z* ]( Y+ X+ p i. l
set intersection? false
' ~5 q( {1 G" Z' e set auto? false! U2 n1 ]- a$ s: B5 `$ P8 q
set green-light-up? true
; `+ ^! a Q! N8 D' Z. m set my-row -1
/ ~$ h- H1 ?/ r/ N0 Z' ? set my-column -1+ z2 I& B; z$ D2 ?5 ]
set my-phase -1
6 ^" S8 e$ N# B4 X set pcolor brown + 34 D3 f! C' o. ]; q+ N7 P# m( t
]4 Y/ c9 Z! ?, g1 w
, p! }' } C" R F$ _# d! ]
;; initialize the global variables that hold patch agentsets( G, m; N! D% Q7 p* H3 r
set roads patches with) c' l% e+ {3 X
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& p) B( L- l* h3 S3 a8 ? (floor((pycor + max-pycor) mod grid-y-inc) = 0)], J3 v" H5 D* d
set intersections roads with' j3 p( u" h4 J) [1 C( L
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and9 ], p0 S$ S; H. U
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
0 }, f/ [& s3 u" x: a& u4 y, U$ G% R, y K
ask roads [ set pcolor white ]
* h# C0 {6 H5 Z7 U _9 S' Z( y setup-intersections* i7 e4 |/ D2 h5 x
end! Y' A8 F/ e j4 [' [, K) Y' |# S
其中定义道路的句子,如下所示,是什么意思啊?! v0 O. O2 U3 X! ^& u8 ^7 _/ ^
set roads patches with
) f% y' i( A% b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 N9 t* E5 Z5 f2 D5 Y7 K& H; b (floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 r3 p. D4 |& h% n
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? |
|