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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。
* z" c: y: x4 J( a0 u, ~netlogo自带的social science--traffic grid这一例子当中,# H% C+ M) ~; {, V4 r2 b
globals6 K4 v F& U5 F- L( m
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grid-x-inc ;; the amount of patches in between two roads in the x direction
2 @' l1 l) c$ C6 m% F2 G8 o6 X grid-y-inc ;; the amount of patches in between two roads in the y direction
8 j. C- l0 M2 u/ [+ c% A. }4 a acceleration ;; the constant that controls how much a car speeds up or slows down by if
% r, z! q+ C. ~, |: N ;; it is to accelerate or decelerate
2 ^$ o4 q7 ~. K# d. {- b3 N phase ;; keeps track of the phase2 v% m; m, C# x( U) T3 \+ _ U
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure3 [: H* u2 N$ `5 |: R) ^
current-light ;; the currently selected light
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;; patch agentsets
% E! X$ X. y6 I intersections ;; agentset containing the patches that are intersections
! V$ N9 s0 ]: W, A) s$ q- C+ ^9 ` roads ;; agentset containing the patches that are roads
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- h4 t7 ^& l8 c% xturtles-own
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speed ;; the speed of the turtle
5 C+ n% T3 K O up-car? ;; true if the turtle moves downwards and false if it moves to the right
2 M* P. ]+ I, s# j; h wait-time ;; the amount of time since the last time a turtle has moved/ U, t. J0 @: R
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2 V2 H) K0 z" x* gpatches-own
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) V0 j$ Q ^2 P0 x4 v intersection? ;; true if the patch is at the intersection of two roads) U7 p, c1 x# ~9 b( b4 w6 Q3 y
green-light-up? ;; true if the green light is above the intersection. otherwise, false.# N% l. j# V; M7 g& X" }
;; false for a non-intersection patches.
# i& c0 ~7 ]3 p7 s$ l0 j my-row ;; the row of the intersection counting from the upper left corner of the# e# L; J! }8 p& e3 m
;; world. -1 for non-intersection patches., v* e* x( a9 H. a% m& g( _5 B/ g, u
my-column ;; the column of the intersection counting from the upper left corner of the( {+ _" v: S% d: f& ~
;; world. -1 for non-intersection patches.
, Y3 D7 Q- S- B& x9 S my-phase ;; the phase for the intersection. -1 for non-intersection patches.& Y& r$ |% t$ E
auto? ;; whether or not this intersection will switch automatically.9 q4 X( r0 a- p
;; false for non-intersection patches.' E* E/ }5 w: _ d% ]2 Q, A" z* Y
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;;;;;;;;;;;;;;;;;;;;;;
# s( g4 E# a6 m8 J* r. a7 L) [$ C3 |;; Setup Procedures ;;
6 G$ N2 ?) A4 |5 {$ P; s8 V2 \7 k;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.: c+ B1 ~9 U% F* K2 N, T; Z4 ]1 k
;; Create num-cars of turtles if there are enough road patches for one turtle to m- O F* D. z' I9 K9 _
;; be created per road patch. Set up the plots., g$ h2 T" _; S: }
to setup1 E8 w: t: M( L9 x2 v& e
ca
( H( B2 v" E3 O/ j setup-globals
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;; First we ask the patches to draw themselves and set up a few variables# i8 @ I; z2 L- Y- A" Q1 s$ j
setup-patches( P1 n. w1 D2 v) e" S$ _1 k4 T
make-current one-of intersections* H1 c! p# k6 K: W. L( f' `5 I
label-current" l5 d$ \5 r8 u! u2 N9 `
, B C) ]0 I" O" f1 o8 L4 v. e set-default-shape turtles "car"1 A7 ^5 ^1 f5 i5 y- ~
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if (num-cars > count roads)
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, t3 T: h* }) S7 Q/ o7 u+ k0 E user-message (word "There are too many cars for the amount of "
: Q9 O6 F0 A- @ "road. Either increase the amount of roads "+ K" g. c) ]* z. ^
"by increasing the GRID-SIZE-X or "7 j& S5 h' `! f2 Z3 }# f; T9 |
"GRID-SIZE-Y sliders, or decrease the "5 Q% d5 o2 @1 [7 [$ B
"number of cars by lowering the NUMBER slider.\n"
2 y' k3 B8 U6 X" T, H "The setup has stopped.")$ U0 R9 ]0 J% B2 P* ~
stop
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+ q: m6 j" X( i& j ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color- Y4 V8 ^* q! \: h$ v0 `
crt num-cars
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setup-cars \; T1 Z4 \8 L3 C& E
set-car-color
4 ?/ a' w6 w( x. \5 b record-data$ k1 ]% }1 g' w; U- Q7 ~
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;; give the turtles an initial speed
6 c* @7 y5 t1 ~0 _ ask turtles [ set-car-speed ]0 W3 _# H4 n" { R7 ]; R) o) A8 y
- Z" j2 [- M5 x$ z* [! p' z0 T# [ reset-ticks" a& \" Z6 `, \ h! _8 C2 ?9 A6 U
end3 w; R$ B6 Z7 ] a9 W. x1 A+ c
7 ~( J Z" u3 K5 p. K! z;; Initialize the global variables to appropriate values5 z/ [* M/ e# ?+ R- R
to setup-globals
2 r7 m9 S4 t1 [: S/ M! U set current-light nobody ;; just for now, since there are no lights yet
" h$ d' ]% I5 D set phase 0
( o# B- ^) }4 Y t7 w+ b/ {( R set num-cars-stopped 06 @8 l6 M5 C. d% N9 E4 ?$ ], c. u
set grid-x-inc world-width / grid-size-x1 _/ _ I* p7 V; Y! N- H+ y2 @1 ]
set grid-y-inc world-height / grid-size-y( j, C/ S& F1 k
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
4 k0 ?- @+ v- `2 U& }4 j set acceleration 0.0993 \! T2 G6 e2 ~2 ^/ E$ T* a
end. R5 \. Q/ ~2 N2 H
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
! t6 B: z @, C) y' j;; and initialize the traffic lights to one setting" w% m( P. e9 m! y1 V9 ` h
to setup-patches
( }& F4 q. D* ?/ |. I5 g ;; initialize the patch-owned variables and color the patches to a base-color$ j+ w$ b! f; b$ Q# r9 Q
ask patches) q+ k h& ] X @# m7 _- J
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3 H5 F0 O& ~9 T! |9 g set intersection? false- Z: M: j) B1 ]# v8 |, `) V* g
set auto? false/ F. j+ G0 b9 m E' i. j1 n& X
set green-light-up? true
( j+ e) C! T5 [5 U* u# | set my-row -17 `% Y- [2 w0 g0 T8 [; j, f/ ]
set my-column -1
8 [; r% k3 k' o+ g* h' x4 Y set my-phase -1
3 ~* e9 Z& Y, V+ D0 v. H set pcolor brown + 3% O5 e7 G8 t7 ~# h
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;; initialize the global variables that hold patch agentsets
8 N1 r) e6 P" X/ ?- J( F set roads patches with5 O$ S9 @& m. E6 |; ~ C" j' E1 P
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or% t1 U" S; z: t& Z4 A9 m9 K7 O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]' g; k! @0 M+ |3 D0 }
set intersections roads with0 t) u# Q9 ]! o7 S
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
* H$ X' ?& G4 I& ^% ~) J# O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]" _% B/ Z; x- Z0 ~
setup-intersections$ N& j1 X7 h S$ {" w
end
9 X, B, @( N1 w4 Y' O/ R. p. |其中定义道路的句子,如下所示,是什么意思啊?
0 C% n5 P! [/ I& v# [6 D set roads patches with( y) d% \4 r1 f! L, Q
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or, x% ]" w# X' b8 B6 Q
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 P" V# i5 Z; u" 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? |
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