|
|
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。5 c1 F8 `+ C7 S! T( A ]3 Q/ `! \
netlogo自带的social science--traffic grid这一例子当中,( z( b s- q' u2 i" |
globals
! A2 F, f1 ?3 {6 k4 {[
3 W- R% y' t$ o. F& q grid-x-inc ;; the amount of patches in between two roads in the x direction4 ]* `3 S4 L6 V
grid-y-inc ;; the amount of patches in between two roads in the y direction; i( U, V! b# \4 g2 V: ?0 n9 k/ ?
acceleration ;; the constant that controls how much a car speeds up or slows down by if
5 b( \% o$ b! z( U6 n- n3 B# y ;; it is to accelerate or decelerate g, s$ F, [( v
phase ;; keeps track of the phase
6 [. j. F1 ] y% C" o3 U8 d: J num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
7 x4 y. ~7 J1 V' h; B4 b current-light ;; the currently selected light: b! k( H& H! k! R1 R8 X6 n4 g
1 E" y2 ?$ D6 |- Y* g
;; patch agentsets
/ g: `+ `5 N& f) _ intersections ;; agentset containing the patches that are intersections
, w& Z, Y2 T/ r/ U' v( ~ roads ;; agentset containing the patches that are roads
0 s, [5 d1 S* ?1 {# P# O]
; N; @; d- N0 b# O5 X' z+ v B* s- ?. l" n+ i1 P5 J0 T4 ^( K
turtles-own
7 B9 G. U; R, I6 `1 O7 L2 G# i5 t[
9 U8 s% k; c R6 v5 a speed ;; the speed of the turtle
! L# d% [: D, V5 @0 e: Q K- n/ X up-car? ;; true if the turtle moves downwards and false if it moves to the right
, } T$ f# H$ p3 R1 Z wait-time ;; the amount of time since the last time a turtle has moved
$ m( b0 M2 C2 R8 Z3 \/ B! e8 d]6 e) t$ u( P7 ]. ~% U5 S
4 F0 e3 n& {% v' i S
patches-own, c7 E/ y; x; `; }
[
1 y. V" j- W7 B9 J/ e1 j intersection? ;; true if the patch is at the intersection of two roads) }+ P `6 W3 d5 S9 t
green-light-up? ;; true if the green light is above the intersection. otherwise, false.$ P- E( d& y w/ A& h
;; false for a non-intersection patches.
2 }: B! B1 q0 B+ C v o" b my-row ;; the row of the intersection counting from the upper left corner of the2 v; m x7 ~. b) b" {% l
;; world. -1 for non-intersection patches.
+ k: F2 h. @. `8 z! k my-column ;; the column of the intersection counting from the upper left corner of the
3 @; \ z, i' q+ @0 r0 @ ;; world. -1 for non-intersection patches.6 U/ X9 F) K7 Y
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
( [( J; j6 q7 U3 H2 m2 l+ T auto? ;; whether or not this intersection will switch automatically., l+ |1 C/ T/ }( l( s; f/ b$ x- ~
;; false for non-intersection patches.
' |5 O& m. f/ I1 r* x+ []7 j" H4 j' \, a* o& X' `
$ O0 s( j3 e% E5 S$ R& o4 |
6 o5 \* L& L, k& z: g" u;;;;;;;;;;;;;;;;;;;;;;
+ Y b7 W1 d+ [, Y5 [1 K% M8 R& d6 I% T;; Setup Procedures ;; ?( s* a+ t3 n0 |3 V5 i
;;;;;;;;;;;;;;;;;;;;;;
' H% G4 `* l! w+ P# G Y8 U
+ }" G6 o6 Y, f2 Q) P;; Initialize the display by giving the global and patch variables initial values.
- R* K6 D( A9 K; D% m;; Create num-cars of turtles if there are enough road patches for one turtle to
# A. {4 p" ^5 u! M7 r8 k/ p+ B;; be created per road patch. Set up the plots.0 E+ W3 a9 @ @. h, h
to setup
9 ?1 j) A0 c7 X* ]+ I4 l$ x ca
- C* h& \/ t) P setup-globals9 r+ u$ }) P' J1 n6 X% ~
! ^: h" J9 ]5 S, ]" j/ j9 P$ W, \" A
;; First we ask the patches to draw themselves and set up a few variables
; t# u' F& m1 h: C. p setup-patches- E' q$ h9 |. m2 e
make-current one-of intersections
, ^- x; p8 }: K0 J2 y" K* H& _ label-current1 ? c, i# W: R1 W
' Z' C9 p9 p0 g% h# N set-default-shape turtles "car"
- O- J( H$ [1 t. K" C
3 T3 e8 M! w0 I: z; o& r if (num-cars > count roads)1 l* w* P! M5 u# [; T2 E
[7 |/ |8 h+ a* t) T* c
user-message (word "There are too many cars for the amount of "
" d! c" i2 X! h: l9 ~- | "road. Either increase the amount of roads "
8 e# [) Y. ]% Z: U; k' q# a6 E3 N "by increasing the GRID-SIZE-X or "+ j3 u! X5 Q$ v4 J0 h
"GRID-SIZE-Y sliders, or decrease the "/ Z0 y) q0 I6 u- i' l; |
"number of cars by lowering the NUMBER slider.\n"4 A$ \: v0 u8 N6 U
"The setup has stopped.")
; g% j7 z! A6 k7 Z3 P! t0 M+ M% s stop6 d) x4 _' _4 d% F% N
]. X2 X7 @4 g& U$ Q8 n. A8 c
7 ~# u9 ^# w% y( {( B" [
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
9 x+ ~6 n: W; K crt num-cars5 \3 A6 `$ D2 n
[! n* x# F0 `3 \+ L8 Y2 {0 _6 l' i
setup-cars) W/ m% {2 d. C( g% K. l
set-car-color
8 ~5 {3 k! k+ ^9 r4 n record-data
$ w1 X5 {) t# d* G ]
- m. n9 P( _( c( R/ A2 V) Z, G2 q& l& U" J
;; give the turtles an initial speed
( R% e9 }/ o: F$ `2 D6 B2 J2 b ask turtles [ set-car-speed ]
; P4 J D0 H6 B2 T6 E
1 W. r2 m+ l* b( a6 Q4 {1 x8 e- K" q reset-ticks
* V ^$ _. n% Gend5 k4 G; z/ t5 q- V$ N3 v& ?
9 P- p T8 }+ s A; h;; Initialize the global variables to appropriate values
/ K0 k: H& z1 sto setup-globals9 t' h( {% h5 q) J
set current-light nobody ;; just for now, since there are no lights yet
$ d3 l- f, ]4 _9 W7 K set phase 0
! S: @" |; N& S5 {5 ~7 X! e" W$ e- K set num-cars-stopped 0- L/ [/ Z( {1 F8 E% K5 H: [
set grid-x-inc world-width / grid-size-x
( U- [7 M9 z6 q2 {' `( \ set grid-y-inc world-height / grid-size-y2 s# `! g" z+ `' I) l9 |
- w6 `& ] D# S$ A5 ?
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary% W' c9 x8 H# R
set acceleration 0.099
* E* v( r }# a6 ?3 zend) u: p* q. p$ y$ L- |6 |5 j) n
2 s4 i7 i# v. @4 G9 [ Z% K$ N
;; Make the patches have appropriate colors, set up the roads and intersections agentsets, n, _/ M% x2 X! m& ]5 e3 y
;; and initialize the traffic lights to one setting2 x) {" P+ c' D3 o, f6 O! a: c
to setup-patches* h3 m: D9 o( I# `! l
;; initialize the patch-owned variables and color the patches to a base-color
( M: r2 g1 {3 D. X6 c7 n* D ask patches
7 P8 `3 c/ o' x- ~% ` [. O) Y5 X% T% D! l" g
set intersection? false6 L- [. _* o9 I; G s+ o1 T
set auto? false2 M. c7 K$ t+ }0 J: I/ @6 l$ N' h
set green-light-up? true6 c: [' s. j3 P2 ?8 b- s5 k1 o8 i
set my-row -1
' f& x6 f5 j9 ?+ ? set my-column -1! J2 }# _/ ?2 U1 @
set my-phase -1
; T3 g& a0 c$ a7 _, _) \# d set pcolor brown + 3* t- S* Y1 l, X f: |- c w$ ]
]
7 x% _5 T0 ~, G6 `5 p3 [
" Q. h! _$ p, ]% c% \0 f ;; initialize the global variables that hold patch agentsets+ {, e8 `; `5 N4 ?% x) A
set roads patches with& [) {" N9 i6 O; ~ Q4 C% {2 o
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; | O T( k b0 e* ^1 [
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ w( N7 S6 M% V1 l b% {, R' b) A set intersections roads with( A# a" I. U- w9 a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
: |: z% H! r4 Q0 q: [ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
8 X* Q/ Y/ x \( x7 r! z c# ]1 z3 A
ask roads [ set pcolor white ]7 N1 z( U1 H0 ?+ n; F" ^
setup-intersections, B2 C! T+ v, q- G. P% \ j( R* q
end
& D& i: b% R( v7 g2 M. i其中定义道路的句子,如下所示,是什么意思啊?$ g' k; J0 Y1 r
set roads patches with
& R1 ~5 {8 r) Q c [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& s* h- e. ~: R" Q3 p" }: P; d& ]2 z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# T0 H1 [3 O' B( o- A
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? |
|