|
|
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。& r4 |9 {: s4 R, N
netlogo自带的social science--traffic grid这一例子当中, ], t) n* d: B! g
globals% }0 x4 k+ r- \6 t
[' C' l: v4 T. i* k6 R: P
grid-x-inc ;; the amount of patches in between two roads in the x direction% w8 M' t* { Z) G K: W+ {; Z
grid-y-inc ;; the amount of patches in between two roads in the y direction
; h" l; Q' ~3 |3 O" J acceleration ;; the constant that controls how much a car speeds up or slows down by if
1 {6 T% ]/ P/ a5 \ r" e0 P ;; it is to accelerate or decelerate
" ?. k/ g% w4 ~0 v- U- T phase ;; keeps track of the phase5 ^. B2 W6 w0 j6 x# P0 ]% n
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure t" G4 m4 t" [4 c; c. y+ E3 l
current-light ;; the currently selected light+ |: c, T1 }6 R/ x0 x/ L) T, _& V u8 ?
+ p' s/ ]0 y. u" X ;; patch agentsets
# k0 A4 H) P8 v( b" ^& C& x3 F intersections ;; agentset containing the patches that are intersections+ }1 Q% G0 D, L R3 u) e5 b
roads ;; agentset containing the patches that are roads/ u; Y9 P. q" }. S5 b
]- u9 y* L" n% C% U n% L- Y9 j6 Z
% D' g% L& L5 y0 F. lturtles-own
* [* |6 j: M' e[
, e4 b' ^' Q! Q speed ;; the speed of the turtle, ]4 _6 e; r1 `
up-car? ;; true if the turtle moves downwards and false if it moves to the right
& h$ E7 [1 x p* ^/ Q wait-time ;; the amount of time since the last time a turtle has moved
& g! W; M5 q3 C' a]- E8 W% t& x$ V" v
' q' o, S$ H7 B& o0 `/ ~- P) fpatches-own
+ G/ |0 m4 P2 }, `0 ~3 T[: V# A' l- I# e/ X
intersection? ;; true if the patch is at the intersection of two roads
. Y0 n3 Y I1 S6 o green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- \3 z( q+ n3 u/ J' v) F4 C( b ;; false for a non-intersection patches.! B# b) l( R3 W+ C4 O0 _. n) J- _
my-row ;; the row of the intersection counting from the upper left corner of the6 d/ X4 Y: ~3 h4 T* @: j
;; world. -1 for non-intersection patches., K8 x8 C8 X4 p' e
my-column ;; the column of the intersection counting from the upper left corner of the4 O+ L& L0 R, E j% H1 q- h+ U3 X' w
;; world. -1 for non-intersection patches./ b6 j3 g, t4 i2 u
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
. `0 e5 p& F" |+ O/ W6 N auto? ;; whether or not this intersection will switch automatically.
9 w3 b. Y6 B' M0 ]8 h0 _% ^2 z& u ;; false for non-intersection patches.
f' {% M' L. t( _* L8 b]% r/ l+ y3 h3 B& w& C
' i& f$ S* _" B* h; ?3 ^& s1 ^7 Y2 {
;;;;;;;;;;;;;;;;;;;;;;
& X4 P1 e. d8 N" e' M( m3 r5 k;; Setup Procedures ;;
, {$ a) P- R. m;;;;;;;;;;;;;;;;;;;;;;1 a8 }5 m* x% d' U. }6 v# _9 p
) Z1 x9 K6 O$ O& x;; Initialize the display by giving the global and patch variables initial values.
/ q- \4 e$ C) [. c4 u;; Create num-cars of turtles if there are enough road patches for one turtle to* r1 k7 q) C3 A) q7 V
;; be created per road patch. Set up the plots.4 p3 o; s4 J5 b# y" I1 ?3 [8 h
to setup: V4 I+ j# U ^4 s
ca% i/ z; @( q9 L8 H' P" _7 E' w7 Q
setup-globals
0 Y2 {% u. _! o6 g: l) x: T# p }4 h4 F
0 a. t$ `6 b& f$ ]8 q( L: s; i! H ;; First we ask the patches to draw themselves and set up a few variables
2 m# a+ J8 }% W: r setup-patches+ C: L4 y) E# ?& n9 T! E
make-current one-of intersections9 J8 |. X5 f0 L/ i7 G
label-current
( s+ e9 @3 b3 b" B3 H8 m1 P6 _' [/ J! c
set-default-shape turtles "car"
& w" U; F7 y! [- s0 s" ?
( [1 B: b `, k' `+ k! ~6 [2 w1 @* F if (num-cars > count roads)- t- r% h" ?7 u
[) r$ O4 @' h) m* |) ~ @( V
user-message (word "There are too many cars for the amount of "
# ^' {7 K8 v9 W$ y2 s. Y "road. Either increase the amount of roads "- o8 g. I' ^1 k
"by increasing the GRID-SIZE-X or "
3 X0 `$ Z' \ ~; Z "GRID-SIZE-Y sliders, or decrease the "2 U* }, Q$ x8 }) |) T
"number of cars by lowering the NUMBER slider.\n"& W! l/ V5 k+ A5 X
"The setup has stopped.")" Z$ M# f& P: [+ p0 ~+ Q* t: U
stop
5 h4 H+ j. t! k& i1 ` ]$ Z1 o8 i/ N ^
/ X, ~3 k6 L& m+ `' N6 }
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color4 D; g; m) y: d' O4 G
crt num-cars
7 ~6 [+ Q- z1 q, _ [
3 x6 b, e# b) `8 c' R( @" I setup-cars9 K8 {! D; j# Z4 ^, j- p+ ?# k
set-car-color C5 ?# @$ i8 I- M
record-data' U$ [/ Q- y, m6 W: T! o4 a( e/ }/ ?2 C
]! A- x$ n5 A* [, d0 E$ J) d
! T1 r/ R6 p Q1 d
;; give the turtles an initial speed. o' E" o, U/ m* Y" A- q) j
ask turtles [ set-car-speed ]
, k6 x |, I2 E" A# g1 _4 x7 Q* y1 B( |; t( ^6 O
reset-ticks
: h4 H# k; C& I2 k4 _: R. g5 W: Rend
! D2 N, {$ u5 o+ y
. @7 I# W' }- `# u# d;; Initialize the global variables to appropriate values d# K Y5 U8 G: `2 J
to setup-globals
* r; K7 I' q4 S0 W3 d: v# t: e8 }$ G set current-light nobody ;; just for now, since there are no lights yet* f, C9 z2 @. u8 t+ \
set phase 0( G0 l; o0 h' Y: y- z
set num-cars-stopped 0% T3 h5 u$ P+ F8 L. e( c7 k7 n
set grid-x-inc world-width / grid-size-x
8 ?' J, b) @4 I _3 U set grid-y-inc world-height / grid-size-y6 n& C# u) y5 c& R0 `
# \; X0 f% ?" X0 ^% B( Z
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
2 m+ j) {$ h5 S. J& ?! S ^ set acceleration 0.099' R# R, k: T: z6 t
end5 _+ @4 t3 m. C% o$ E1 k+ x
6 q* d4 _ G0 M' o( Q;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 K9 n1 m' E% u;; and initialize the traffic lights to one setting) Y9 n4 }3 W% ]! A; i
to setup-patches! e9 V1 q4 Q% o
;; initialize the patch-owned variables and color the patches to a base-color. G+ A3 {* [! ^9 [, ]- q! k; o# g
ask patches
* @6 H+ C3 |. g# F [4 W5 A) c4 h$ j3 Y& T9 L/ Z9 V. u: }
set intersection? false
# o# S- l5 c& m3 Q3 c set auto? false
, P$ g+ H8 M& C) }7 N& H: I* z- K set green-light-up? true" f5 A* `& u3 I% X j( c
set my-row -1& i# l* b) {* Y' q7 c# ^
set my-column -1
9 M" D8 {: X& E+ z1 B5 |) t set my-phase -1& w+ i! q" T- p5 d# l) j( x' V& j F
set pcolor brown + 3( x7 u1 T) H0 N6 p, h& c' A: Y3 s
]
+ k% t- u$ t/ Z9 ?2 y3 ~8 q
7 d2 y* l& D; d! O" p ;; initialize the global variables that hold patch agentsets: O/ T. e9 Z6 m R1 u/ L! j/ f
set roads patches with, \+ i- P) l" o6 O% g: _4 t, c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- a3 j0 p, ~& @5 U (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
& E, F6 y7 b5 |4 p5 @! j set intersections roads with
$ M/ M. P! h. k [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
h. r: n" V8 |6 @: Q' g (floor((pycor + max-pycor) mod grid-y-inc) = 0)]( m5 q' c3 J, \' f
1 C F4 q D! ^
ask roads [ set pcolor white ]
3 i/ v8 R: x1 I& T" e5 F1 N6 Q setup-intersections2 L3 W, q& m* x; L+ V$ }
end) j" s: |8 A9 L
其中定义道路的句子,如下所示,是什么意思啊?
( V u j Y' Q/ H6 i1 a x set roads patches with
2 V5 r+ Y9 j* I3 f9 a1 }! C7 U# d [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ k w/ {" h7 c% F. X/ S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 j$ Y2 r* m$ y: g2 ?0 s+ Z' ~
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? |
|