|
|
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。1 T3 g* X1 ?3 g9 @+ I) n( x! T+ m* K
netlogo自带的social science--traffic grid这一例子当中,+ \0 Y# p4 e! E; d" ~
globals$ V) L/ X5 \0 e$ U. |( S
[
0 _$ v+ S0 L8 i. r G grid-x-inc ;; the amount of patches in between two roads in the x direction+ k. W7 ?- X8 x* i) K$ O( \
grid-y-inc ;; the amount of patches in between two roads in the y direction
( G- E$ R2 B; _, I1 N' \4 C$ x) a% d. t acceleration ;; the constant that controls how much a car speeds up or slows down by if
/ @: G. I! ]: e+ Y5 G ;; it is to accelerate or decelerate
+ `* V5 `6 P0 k+ R phase ;; keeps track of the phase% k* p: H' h- M) |3 S: c7 x$ }
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
" X$ B4 \" [, e9 U/ m current-light ;; the currently selected light
) M% y4 E5 _ I0 e- Q- n7 j" d6 E) ]4 u: z* i* n5 L
;; patch agentsets @6 |5 g. C; t6 R; C
intersections ;; agentset containing the patches that are intersections
7 U/ V( C' W6 I( ` k) J roads ;; agentset containing the patches that are roads
$ ]& [. L. ]5 f4 L]
0 Z6 T2 I' x9 H) i' g( ` K9 Y" j+ T* K
turtles-own, R" a2 ^& s$ e
[
/ O. M) e- O' `2 y speed ;; the speed of the turtle" m: ~/ M" u% Y3 v( K1 l. M. i; A" Q4 f
up-car? ;; true if the turtle moves downwards and false if it moves to the right
, y/ e* B* k' ~1 u: k wait-time ;; the amount of time since the last time a turtle has moved+ `" @6 p' J" m: L' y" Y! c
]/ c) ^* g' _4 W
% g& V( G. R8 y) p Z
patches-own
: \1 p. h H% a+ D[
/ s, o% q+ Z8 L intersection? ;; true if the patch is at the intersection of two roads
/ c+ r8 G! L2 c% z green-light-up? ;; true if the green light is above the intersection. otherwise, false. E, f- ^. f& F6 ]
;; false for a non-intersection patches.9 E5 K# j. {, N5 `0 l( O
my-row ;; the row of the intersection counting from the upper left corner of the2 X0 y( x! [; U5 a: H
;; world. -1 for non-intersection patches.2 S4 Q2 v. m0 M. {+ o$ J
my-column ;; the column of the intersection counting from the upper left corner of the, V1 V) \; H! a, X/ ?/ u8 [- |4 ~8 `
;; world. -1 for non-intersection patches.
7 Y: Z: Z3 u+ H my-phase ;; the phase for the intersection. -1 for non-intersection patches.
; @" f6 Q' D5 M! D i# \1 F# y# k auto? ;; whether or not this intersection will switch automatically.
8 f; Z0 K: [ P1 ^0 D5 |8 ` ;; false for non-intersection patches.
- ~ p) X, M. V2 L2 k5 K]7 E ]4 o v- b8 M7 f
& c* X9 t, [( M& [1 I
5 C' z5 R) Q: ]: P# s7 G
;;;;;;;;;;;;;;;;;;;;;;( t8 e/ \5 _* Z1 |- y
;; Setup Procedures ;;4 ?% i0 L) p2 X. ~: N! `% y0 x/ l
;;;;;;;;;;;;;;;;;;;;;;) p4 t0 H; Y: t: [$ f. j) s( Q5 h" D& |
! ^, H& j; }. }0 [4 V# {- H! g) T;; Initialize the display by giving the global and patch variables initial values.# ~$ k4 A1 }2 T, G
;; Create num-cars of turtles if there are enough road patches for one turtle to* X9 T. k( [5 H- d8 V* }
;; be created per road patch. Set up the plots.
6 |; E: `8 w" X9 cto setup
J+ a: j. [' T U l) C- g ca
! r( b4 {- L* B G) @; s setup-globals
7 t) _" w4 U0 Q$ X& \' D$ H! i3 y' ^1 U1 Q5 b5 {0 ~2 F j7 E" I
;; First we ask the patches to draw themselves and set up a few variables
8 f V, p( r" X9 b4 R setup-patches, k5 l! ~$ R, \. m" |
make-current one-of intersections; }% d; b& s9 A) n" P
label-current
! @( n' z1 p+ y1 F- ]- F$ ^) i+ X& z) A6 f* ]
set-default-shape turtles "car"
T& U6 `/ m3 W9 [. y) u' Z- X* d
2 F( r6 Q( N2 F/ S% l if (num-cars > count roads)
# c# ]2 x. y: M1 ~ [
8 O/ x4 O. U. o' J. c3 R user-message (word "There are too many cars for the amount of "
: I2 {* T8 `1 p, \4 Y1 R% S "road. Either increase the amount of roads "
( a8 S6 X# J3 X; s: w$ @ "by increasing the GRID-SIZE-X or "- B/ F# [- ?5 b6 ^
"GRID-SIZE-Y sliders, or decrease the "! W6 w, I& O9 a' ~! y W
"number of cars by lowering the NUMBER slider.\n"& B- Q& [% J y% I
"The setup has stopped.")8 v0 _; e b8 @( Q/ r8 x
stop
" ~2 X0 g8 x J4 u5 Q2 n) I ]- m! f3 X# y/ A* j- W
0 |7 c' v1 Q! }3 h; \0 U& T
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color, v S% @+ O8 j% E
crt num-cars
' U# Z9 J; L( Y1 W [
' G, t3 f% R; _( @7 n# a q$ ^ setup-cars- R& K9 w7 {1 z3 ^, V+ G K6 A
set-car-color8 _- x9 H6 _# k
record-data0 a# x$ g N5 m% |
]' @1 {4 Q! T0 k9 f& M
! F/ O, ^: ~6 a' l2 J( |4 I" ] ;; give the turtles an initial speed
! F: i6 r J; ^) O5 |5 H7 T% F- X ask turtles [ set-car-speed ] e. n. q6 V. g2 Y/ K
; Z$ s9 I2 q4 h; F# S1 E% H reset-ticks4 v; S' n3 G' [2 K( O A! d! i
end" V! m6 Q; F6 O
) a2 ]2 b/ _5 p" Q8 J;; Initialize the global variables to appropriate values
( n+ C0 ^( G, w7 ~to setup-globals3 x5 |9 {9 ~5 c4 i. i. c
set current-light nobody ;; just for now, since there are no lights yet9 R. _8 w" U5 w
set phase 0
1 d% d9 ?! Z) D) O0 x, \! w$ t; { set num-cars-stopped 0! }8 q0 U/ J! I+ v0 a
set grid-x-inc world-width / grid-size-x
! l$ s ^) u, s+ w; G set grid-y-inc world-height / grid-size-y5 k" q3 L: R! H* P" ]3 j5 K
& q( t: U/ ^. l$ o7 F4 F2 Q- } ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
, I0 ]# s& C; r3 r set acceleration 0.0997 n+ _6 b. o# `
end! E0 { y3 \$ `% n. b
/ ]' b' p @/ c( l: E! i;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 K6 i4 s" f& T5 T; _: t& R;; and initialize the traffic lights to one setting
8 J" x& b' V1 t- ^to setup-patches( u- h7 i. l9 R$ F( S" Q5 y
;; initialize the patch-owned variables and color the patches to a base-color
d C' U! e" _0 e: n ask patches, C2 L4 J8 ^( D# g9 T" q. _8 X
[; T7 W) A1 \. r% Q3 j u
set intersection? false
3 b, J6 P! q7 C" R set auto? false
8 v5 N9 m+ h! B set green-light-up? true/ }0 v e# z! w: ~. Y
set my-row -11 k- E& s z. @ Y3 i) n2 r, h
set my-column -1
6 [2 W( j. P. n set my-phase -14 u8 q* M% y! a/ h" @
set pcolor brown + 3% Q$ R/ [$ |5 U* R: L: D
]* e3 y: V8 {+ I' D
k$ u- X- Y8 ]; H' d) e0 l
;; initialize the global variables that hold patch agentsets
4 V7 m7 B1 p$ j% q4 C. k b set roads patches with% Z9 I2 L9 \* p7 y7 f
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& a9 i" ]& f. j! Q1 f+ g" z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 E/ _( @+ J+ R' n8 n' I set intersections roads with
9 g% w8 }7 p) Y1 {% p- S6 i# f/ ]( l, ] [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
$ R- s' H+ [' A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
( J' }; p4 b3 S) V5 ?) B j% Y& L9 ^: X' S
ask roads [ set pcolor white ]
- u/ ~/ ]; y8 Z9 z% Y setup-intersections8 I S7 N: N2 o! S7 J
end
8 [" K, b" b0 N' z其中定义道路的句子,如下所示,是什么意思啊?8 y5 i+ K* C6 D4 `0 C2 y7 p
set roads patches with
0 n# C/ o9 R; ]6 m& Q+ n" T [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
, G; T" _$ w9 z8 ?8 ~% D (floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ F7 B0 ^, q+ X
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? |
|