|
|
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。
9 e! E4 M6 `: h/ d) Lnetlogo自带的social science--traffic grid这一例子当中,: m" q$ X {2 J4 u0 t# v. a
globals9 n: I) B0 L( b5 m& D# ?
[; v1 k4 R0 U$ L' U
grid-x-inc ;; the amount of patches in between two roads in the x direction `4 u+ F4 L' W6 D$ B! B; E
grid-y-inc ;; the amount of patches in between two roads in the y direction
+ @3 W' `6 W" J acceleration ;; the constant that controls how much a car speeds up or slows down by if/ k; G# C) h# ?9 {
;; it is to accelerate or decelerate
4 g1 i$ P8 T! m phase ;; keeps track of the phase( `0 g6 M/ ~" W4 K' \" m
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
9 k/ m, n4 @1 h( v9 L# d7 X3 i current-light ;; the currently selected light7 e: @1 X8 P, K9 z7 E9 e) i( |
/ ~ S8 q' _. A- p/ b5 \" T
;; patch agentsets7 S8 }; L* ?# M
intersections ;; agentset containing the patches that are intersections: s+ f+ x0 H) O2 O; [. z1 Q, c
roads ;; agentset containing the patches that are roads: m# B- \1 W$ |: _ H7 ]
]2 R, b% s5 u7 c
3 S. A; ]2 d) O" yturtles-own
' S1 {0 b8 C% n' x- E[
' @/ y, [$ x' M% W4 T speed ;; the speed of the turtle L [" B, C& j- A/ H V5 b" T
up-car? ;; true if the turtle moves downwards and false if it moves to the right
1 @) k. z+ T/ u* f& E* g wait-time ;; the amount of time since the last time a turtle has moved
. r, J) y% d2 h; f]
* J4 \/ M, a) {3 i& V0 L7 j) \
" W9 [; Q2 a+ Y2 a3 F# @patches-own
1 _0 e8 ^2 G* {2 Q' c: g/ z[
* m0 z) X7 R7 M, @ intersection? ;; true if the patch is at the intersection of two roads1 u7 X( C( \, k4 S8 K
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
8 `- i! {! X: a1 W# m ;; false for a non-intersection patches.
* R, `& ~2 w# _ my-row ;; the row of the intersection counting from the upper left corner of the
" ~: X$ s. n: [8 o5 J ;; world. -1 for non-intersection patches.
* K" F$ I7 C7 d0 ] my-column ;; the column of the intersection counting from the upper left corner of the
! v+ y0 v, z% H+ L ;; world. -1 for non-intersection patches.$ r+ v/ j( `6 c) w: K
my-phase ;; the phase for the intersection. -1 for non-intersection patches.' h3 k2 S9 I7 L5 a# N8 r
auto? ;; whether or not this intersection will switch automatically.
& `6 L- ^- G& t, q0 }8 t( m ;; false for non-intersection patches.& U; G! r+ y5 m$ u% x% ]
]% D) K* S6 ]0 T7 a3 ?. I- t, Y
|3 \" J0 g0 C- m; m4 v+ ?( S
- V2 I1 E' G0 {;;;;;;;;;;;;;;;;;;;;;;1 P! }& Z8 S) g( E1 u
;; Setup Procedures ;;
/ m; z7 D- N! p% k;;;;;;;;;;;;;;;;;;;;;;
) c7 ]: X3 ^5 `- X1 I H9 }3 |7 H: f2 _5 L* Y1 X* @
;; Initialize the display by giving the global and patch variables initial values.
. U/ v+ A3 l5 m6 I9 j0 V- d;; Create num-cars of turtles if there are enough road patches for one turtle to
0 }+ E+ Z; w3 X2 i;; be created per road patch. Set up the plots.9 ~( E1 ^/ j+ B& J
to setup9 ~# y: c4 t8 C. h, r+ X! K
ca
1 M# Z8 w- w5 V9 L setup-globals% I4 }' M: N. F9 d
- f R: j! K+ |1 g
;; First we ask the patches to draw themselves and set up a few variables
( B6 b; J u) U setup-patches4 a+ z; v9 w* `1 H. d* ]$ |/ [/ m
make-current one-of intersections7 S& X* |8 v# I' `; b
label-current$ F( e/ m, R+ ?
8 W3 _( u% p5 Q, r
set-default-shape turtles "car"
' I. E j3 k6 l# D3 v' l$ W" ]2 n7 Z0 x" X8 ^; @& j
if (num-cars > count roads)# | F! ~% V! r
[+ A0 L/ ?( V, [0 L" z
user-message (word "There are too many cars for the amount of "
2 g) ?! f# {, s# d+ ~ "road. Either increase the amount of roads "& q% y0 K1 B6 Q* @4 w* v: M9 c
"by increasing the GRID-SIZE-X or "
5 r* {8 Z' T' \9 F "GRID-SIZE-Y sliders, or decrease the "" Z1 V" [' y+ e, |" o. n
"number of cars by lowering the NUMBER slider.\n"* y- y2 c/ V, H; T* q
"The setup has stopped.")
. e( g: {$ |3 { stop2 R0 Z8 A% L- ?" O
]" S$ I! v0 P# c3 C" i4 l
) V" B# c1 z2 P0 C( Z
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
4 Y5 O9 d2 T- o8 {; R' C, d3 T* k6 H crt num-cars
- ?0 y9 B4 ~: Z6 T% e [
% D. K" d3 _& q setup-cars
5 f n" @" j; j6 H7 [: w set-car-color. `' y a7 w8 N9 N# {7 v8 {- P
record-data/ U+ u+ {5 Z) L; i$ W. I# Q+ H3 M7 T! K' E
]0 I4 p7 t% B- i* ?( n2 \2 {+ }
+ O+ W* w, [$ y# j3 G4 s. }) ~ ;; give the turtles an initial speed
$ c; Y3 S% S" v ask turtles [ set-car-speed ]
* j/ T. F# |- [4 g* m0 |/ b9 ^1 g! V5 O7 D
reset-ticks
9 j; m8 O. Y+ `0 M3 oend, H0 [) A: O+ _ ?+ [. I0 o
+ @4 q* l$ {+ v5 b: G: t% X: I3 |;; Initialize the global variables to appropriate values
; w3 r) x* l% J' G, qto setup-globals4 [+ V* F" u5 C+ r' p% L& k+ D
set current-light nobody ;; just for now, since there are no lights yet$ |: N# ]* j$ \! y8 }# |& x$ Q/ z
set phase 0( p P5 l8 t# K4 d! K- b, Y
set num-cars-stopped 09 k" a; @( ]" l Y( C7 t
set grid-x-inc world-width / grid-size-x' E* [! \9 O, I1 q# l
set grid-y-inc world-height / grid-size-y9 ~3 i/ Q5 M2 G% ]1 N) ?. P
! o) _; } _8 j5 q+ ]6 C4 T3 F9 @! @ ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
5 \# |! G6 D+ f; F. R3 ~- c set acceleration 0.099
7 b( x% P( D9 z# K* M2 e h3 Gend; w3 N7 N9 m: Q7 d6 J; o' V9 A
/ d* }6 E- U( D
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 l8 b; p2 u1 {. @# H;; and initialize the traffic lights to one setting
. w* D; ^4 \2 h6 P4 nto setup-patches' G0 ]# c4 w8 `) P% L
;; initialize the patch-owned variables and color the patches to a base-color/ P( {- i( `6 p4 k8 I/ }
ask patches; \7 n0 N& h$ n2 q. E$ x `6 `0 ^
[
0 S/ U0 j9 I( M- E8 Z( E8 {3 q* R set intersection? false( A; y6 ]* B, @( o8 U% P: D& u6 e" R
set auto? false* A$ g& S" `6 h0 ~2 K
set green-light-up? true
: E/ T2 \' @: f7 t. X; W7 b. C- u- D set my-row -1% T" ^0 ?+ D: G3 j
set my-column -1, H* i& ]. d) { T
set my-phase -15 o8 o! }4 j7 ^ @
set pcolor brown + 3
2 [! f$ d1 M9 e9 F3 X6 S ]
: Z; V, p! ?% y7 t8 [+ D0 _2 q: Q! X) a, d" p# @# Q4 u6 z
;; initialize the global variables that hold patch agentsets V6 ^+ V- v9 Z5 H1 y# H0 k
set roads patches with5 F7 I; B. Q8 @4 E" d) k
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or' {* P: [6 x4 }
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ h' x' [! Y @- [" F set intersections roads with, F( w7 Q. t" I
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ m* X2 Q3 _& ]% V; l2 Q (floor((pycor + max-pycor) mod grid-y-inc) = 0)]1 u, M' F) C1 y" {
% E$ B# l) B; F n) @
ask roads [ set pcolor white ]
8 o/ R3 I* o1 D setup-intersections
2 v% |9 v! D& v# aend
0 g5 h( r B/ J其中定义道路的句子,如下所示,是什么意思啊?( l+ I" U3 b+ P$ n/ w( s) [5 ]
set roads patches with' G) d9 s% j" a( a2 U h4 n+ \
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% [# ` B1 @5 X- }' o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ ]5 @) F3 h& D. J) J& w1 H# F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? |
|