|
|
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。
8 J+ C6 `2 i: e: _netlogo自带的social science--traffic grid这一例子当中,
! m% x$ c4 G, L2 U8 Bglobals
% }: m1 O6 } T. _: S: O+ R; Y[5 J5 G9 l. b" m8 i8 o
grid-x-inc ;; the amount of patches in between two roads in the x direction
; Y7 w: B5 y, m" K grid-y-inc ;; the amount of patches in between two roads in the y direction
- K3 M% _6 b3 \2 C( @7 ^0 r acceleration ;; the constant that controls how much a car speeds up or slows down by if
, {4 g" n( s( K- ^/ a9 C ;; it is to accelerate or decelerate
* [ i6 C6 i8 G. o1 o phase ;; keeps track of the phase
& S& D) q ?" O. v: o num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure" f# j3 G" K- P9 Z* k6 e% r
current-light ;; the currently selected light l& k- {) h. i$ }1 O8 p) l
' ]% E! a, P) g. z
;; patch agentsets
0 q, g) k0 l" p o) n intersections ;; agentset containing the patches that are intersections4 l3 w. R- g4 c" K4 h# ~& z, W/ ^
roads ;; agentset containing the patches that are roads
. W) S8 u" I1 w; W! d]+ N5 @/ Y% Z3 G" ^4 N( F
9 f( c6 { @3 d; ^turtles-own
" {) m8 ~, ~7 c7 _& ^# U[
$ M) ^1 A! E8 x) ]2 k- M, H- ~ speed ;; the speed of the turtle2 z& _. _; r$ V5 x! y3 S
up-car? ;; true if the turtle moves downwards and false if it moves to the right* w8 ~4 b4 s4 b/ Y& L
wait-time ;; the amount of time since the last time a turtle has moved
) L, p) H4 {# v% w" C/ Q+ O]# e& I9 E( `7 N
# S. Q0 v% I3 y0 hpatches-own
3 W* H$ g$ {! i6 }[6 ~, T$ F, a! r, U% u) O. ^( b2 m
intersection? ;; true if the patch is at the intersection of two roads4 Q. J# B% `' j6 H+ t4 s9 r0 w
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
" }4 c+ u9 [4 @. U5 H7 K ;; false for a non-intersection patches.
# r$ b$ `& E _7 z my-row ;; the row of the intersection counting from the upper left corner of the
9 P/ \# g9 c9 Z" z- O+ c0 G: ~ ;; world. -1 for non-intersection patches.
8 O% }7 ~- v* z! c& m$ g Q my-column ;; the column of the intersection counting from the upper left corner of the! W8 e. _; @: q: v" ~2 t# B
;; world. -1 for non-intersection patches.' a* {2 d L: v9 H
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
4 A5 q7 Q/ k3 G; A. u* @) R auto? ;; whether or not this intersection will switch automatically.
* U3 k. E5 t6 I5 c9 n! O ;; false for non-intersection patches.
; H; T# k6 c" N+ V4 E]2 P* e8 @& z# R1 O
/ p7 o, T9 ~$ I6 N7 n4 v
3 J' Q1 X1 E/ t
;;;;;;;;;;;;;;;;;;;;;;
. |$ _) H$ {& }. }3 n( |2 A;; Setup Procedures ;;
- ^1 {1 ~: }7 j;;;;;;;;;;;;;;;;;;;;;;
8 q8 O# H, u( b o* W- N, T: ?; \1 C/ x7 |
;; Initialize the display by giving the global and patch variables initial values.; p% {. m \: `9 h& @( ?0 S
;; Create num-cars of turtles if there are enough road patches for one turtle to
7 \6 j; h$ L r* V- i9 c/ L;; be created per road patch. Set up the plots.
7 h: \( b# ^& j2 F$ vto setup) a5 Q3 q0 b. t0 D. R* L; d8 N; `
ca0 O4 m6 U7 T$ [0 ^, J# z
setup-globals
0 w! N! v0 ^. B
# K( \) i- u* I5 m ;; First we ask the patches to draw themselves and set up a few variables
+ @7 A3 ~9 M1 Z& J! i7 ` v setup-patches) ?1 ~& Z5 X: E4 p) G
make-current one-of intersections6 k2 U* D; r0 i; q3 s
label-current
! e7 Q9 c- ?, _- [1 h/ g+ a( U% V
9 A( u9 }, ]! A: W+ R+ y set-default-shape turtles "car"6 T9 |1 P5 m8 c% ?+ z9 a' ]
, i* g+ V I7 W; z! T! A8 s% ` if (num-cars > count roads)
$ H5 t8 R( t- m- {, e3 H [
* q. O+ p% S; z$ T user-message (word "There are too many cars for the amount of "
" C; g0 f, x b# u0 }- G: B "road. Either increase the amount of roads "8 [( Y$ D% y$ M9 c' D% O
"by increasing the GRID-SIZE-X or "/ n# s1 n4 d- u2 J
"GRID-SIZE-Y sliders, or decrease the "
4 h0 ]+ x0 E8 J8 l "number of cars by lowering the NUMBER slider.\n"
) B5 {: h- N* ]( k9 y3 U "The setup has stopped.")
. B5 Y6 a1 V' y# { stop
9 H/ v* T& A. s2 K! D3 A. c- n ]
& h% K$ v( T# s; j7 r' b
. O0 s, k2 G0 @7 _ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color w7 p/ J' Z9 y* a( h
crt num-cars, t/ }) C7 z) `" p6 a i8 x0 c3 w
[# G2 \5 D+ ?& f: {" i
setup-cars
- ?4 f, f$ a! `) j8 U set-car-color
$ Z5 j3 R- {0 v% Y4 c record-data
" m! a$ @) Q7 k/ ?+ l ]1 f( @6 L/ I8 `+ A3 |& A
) y0 k; }1 ~0 G" u& W( n% _4 h
;; give the turtles an initial speed2 V' @- H- z, C% X5 h
ask turtles [ set-car-speed ]
+ l6 B. h7 t' C5 y' \+ M
3 z/ q" e+ X7 T; W reset-ticks1 o, T! a7 @* T K& M
end
4 K4 _, d5 P4 e' F1 G9 v8 I2 B3 Z& |# J0 {7 I+ D' ^
;; Initialize the global variables to appropriate values# J* l5 D8 u+ J% v: ?
to setup-globals$ A4 M7 G$ _7 j( p/ ~ Y5 L2 w2 e. t! r
set current-light nobody ;; just for now, since there are no lights yet
0 {4 v, X' d9 \& J) p set phase 0, d: e, b2 x/ ?$ u6 d. p$ {
set num-cars-stopped 0* K; ~) k! M$ [& u1 O! `
set grid-x-inc world-width / grid-size-x( f1 j# E7 O! j8 q
set grid-y-inc world-height / grid-size-y' s$ @& T- C. w, y: E
9 a# ] Y3 `- d0 o9 N& ?( U$ y5 N1 c ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: `8 u3 S7 H/ y4 r
set acceleration 0.099
5 y* ]% a6 v S( B5 Rend
4 W8 s( k. Y1 k& U Y
% C6 W6 |2 I8 u0 F- D% w! A;; Make the patches have appropriate colors, set up the roads and intersections agentsets,, a6 U8 s7 y7 o" G/ E2 T
;; and initialize the traffic lights to one setting
3 N, n' Z& [% U; uto setup-patches# M1 M, y7 t+ O+ [3 E; s
;; initialize the patch-owned variables and color the patches to a base-color
% `3 e3 V( U: V4 N# y& d ask patches; `1 i. @) a2 N% b2 m! g
[- C, o* r; W5 B' m& [( s
set intersection? false
1 p I6 f5 j- ~. y1 f: Q set auto? false
3 z0 I% J- B0 Z9 ^, F- Y+ `3 @ set green-light-up? true& W! j$ n9 }; h P
set my-row -1
, N5 o# U( f/ @ K" R set my-column -1
z4 w5 l) L9 l1 Y. d2 `0 z set my-phase -1, D( ]+ ~% C. r8 B1 ^# \4 g9 ]
set pcolor brown + 3
5 b7 E9 d4 F1 ~" W. G2 }+ p8 y( t ]4 A: ^, |% v, T% W3 F
# r- L( s' m8 A1 j9 G ;; initialize the global variables that hold patch agentsets# F3 c3 q+ P! T. `% _
set roads patches with) P; B2 m% U, i/ n Y8 O9 c7 ^4 a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
: F9 o! a; |( r# C& |- C (floor((pycor + max-pycor) mod grid-y-inc) = 0)]: R% @9 R1 X1 r5 y( z
set intersections roads with' t# k/ V1 g7 Z" d. c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and% v$ T- E; n. Q: I+ b R ]
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
- o# d8 A1 {% V, D5 t( K
. g. `- X9 X2 }9 ]; k ask roads [ set pcolor white ]
8 S; @" P- F4 {/ s4 o setup-intersections
: c( O& d |+ y" vend4 h0 z0 v1 W7 [" `& \2 s! B/ A) B2 P
其中定义道路的句子,如下所示,是什么意思啊?
K, v8 O5 }9 b2 C1 s: P( R1 _0 y set roads patches with* R+ ^0 x9 {5 |+ `
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ u7 n/ y) O: R, p4 n; m
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# R8 A2 V% I' n) O& H$ 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? |
|