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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。8 ?6 Z* X. }* _2 }. y( v6 h/ |
netlogo自带的social science--traffic grid这一例子当中,% R; ]" I! K+ ~: i4 n+ k
globals
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$ M6 n7 G6 S, ?7 I" g: [* a( A grid-x-inc ;; the amount of patches in between two roads in the x direction; ^. J/ _+ }7 D
grid-y-inc ;; the amount of patches in between two roads in the y direction
. u! M$ B( A. D) _ acceleration ;; the constant that controls how much a car speeds up or slows down by if3 a) A* d9 i" S4 j% V r' Y& s. R
;; it is to accelerate or decelerate
; d2 \3 h' g1 V' K8 q u phase ;; keeps track of the phase" s8 \0 ?- x3 K2 s* G5 L/ M( q
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure5 G8 @1 B# q; m. T
current-light ;; the currently selected light4 W) B. V, N$ @; L) Q# A W2 ~
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;; patch agentsets
# O3 }1 \$ f+ i& T5 P0 p# f intersections ;; agentset containing the patches that are intersections6 D/ T5 Z+ g: H: u- v$ k n
roads ;; agentset containing the patches that are roads3 I5 u+ s' U& P% W7 }+ j
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turtles-own' o1 H/ ?; `5 U2 \, n
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speed ;; the speed of the turtle
* ~' r9 W$ m; @9 Z& m$ E2 \; g up-car? ;; true if the turtle moves downwards and false if it moves to the right+ ^. E- n* e4 F. A% {: B
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads0 ]8 r% G. r: p# b# }+ J! E6 N
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
9 N+ ^+ O; N8 l$ s: o ;; false for a non-intersection patches., g% [* y( O, w g$ M+ P
my-row ;; the row of the intersection counting from the upper left corner of the
5 h( s: Q# j4 e3 o: H3 V4 J ;; world. -1 for non-intersection patches.
( J6 p5 K/ I% d! G$ ` my-column ;; the column of the intersection counting from the upper left corner of the
`& p; k4 V* g6 @( J, n$ r ;; world. -1 for non-intersection patches.
9 X: g+ \7 Y3 C$ } my-phase ;; the phase for the intersection. -1 for non-intersection patches.
. \$ d+ M ~: E$ b, ]1 O auto? ;; whether or not this intersection will switch automatically.8 h7 y6 G* O9 f! Z
;; false for non-intersection patches., b+ C8 k* m0 {( W r( f1 c
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& H. U9 d+ @7 a8 y$ C' q" Z;;;;;;;;;;;;;;;;;;;;;;
& Q7 t. \( j6 L8 v3 l* e$ q;; Setup Procedures ;;4 b5 r; u ^7 O0 R. m S: p8 b
;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.
; L6 o4 o. A$ F- @( B;; Create num-cars of turtles if there are enough road patches for one turtle to- r# @( L9 f7 [+ b0 e L1 U" ~; f
;; be created per road patch. Set up the plots.: t6 e, `% a- ^
to setup8 T; C7 M* p |6 h- c3 G% M$ \5 T
ca
/ I3 P! b" n+ [9 G. {, E setup-globals% S a+ Q. p7 K* P2 o7 Q! J! Y) n
5 b$ U' x7 j7 K. a ;; First we ask the patches to draw themselves and set up a few variables
% B2 ^/ a: g+ ~$ `/ M1 | setup-patches
- q- c+ i( O4 }* X5 q! p- c; E# K( s make-current one-of intersections
3 ]" e* V8 M' c label-current7 |3 y7 f0 m* H! p
8 O1 {* |7 Q; F: T: X, a set-default-shape turtles "car") u* n* `! g5 T4 V- `
- E, n6 R3 k% j9 _/ p# ?& o+ h if (num-cars > count roads)9 W, v) b# O$ d& q: w
[
. n+ \7 v/ c6 |, C/ I5 i" G user-message (word "There are too many cars for the amount of ". d$ ?* x" |% t. a6 m4 \
"road. Either increase the amount of roads "
3 y; T1 k; C% [) @# o/ M "by increasing the GRID-SIZE-X or "
7 Q( ?# g7 g- b9 q$ V# @+ I "GRID-SIZE-Y sliders, or decrease the "3 I8 k% t* o7 J. w! x
"number of cars by lowering the NUMBER slider.\n"
5 x0 x L" D& F) D4 D1 ?- J# q "The setup has stopped.")
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# q2 q! u# W, G3 v ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
: i. f) p# ?) w5 a; C5 L crt num-cars3 |) U, o7 z: g! t6 s6 o! G
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setup-cars8 z' r# z8 T, z/ y) A
set-car-color
% l2 ^5 ?; a( G3 P6 z+ A" ?$ e record-data! z: E/ [, q' W/ t3 T, e# ]; b
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: r) t1 P% q+ m. k1 G# |& |( U ;; give the turtles an initial speed# H/ y P" Z/ N1 @
ask turtles [ set-car-speed ]6 H; {1 D% _& {
0 N, F8 a6 t) ]+ a5 ~ reset-ticks# ?0 w; f8 H2 \7 M$ `3 ^; |
end+ S) u. [; g/ P0 D0 C; a% S9 e2 y
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;; Initialize the global variables to appropriate values% B* r2 ?' O7 A& f* b
to setup-globals
0 e; ?9 o6 q1 L4 B2 f e set current-light nobody ;; just for now, since there are no lights yet- M3 u) f. a5 U5 c T
set phase 06 T" G4 O8 p5 f1 e, X$ Y
set num-cars-stopped 0' W g- ?7 B4 y0 |: t; }/ T
set grid-x-inc world-width / grid-size-x
" T& e* _) F+ l* B2 |, A4 e set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
; e! `- ~+ O/ [9 r, _ set acceleration 0.099# ]* I3 B U; P3 w- n
end2 w5 A/ J/ _3 {% Z
0 w8 ~/ ]+ r) y4 ]( S- b" k4 u5 p;; Make the patches have appropriate colors, set up the roads and intersections agentsets,/ S' @" d' _$ A& E% Q9 Q. D
;; and initialize the traffic lights to one setting
1 l" E5 J0 G. Tto setup-patches* L( ]# e+ n3 i) Y" W0 Y
;; initialize the patch-owned variables and color the patches to a base-color) a6 N# @' a7 J, x9 Z
ask patches
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% d3 _, x6 v7 B1 e1 ^, c! ? set intersection? false
0 p: j6 ]2 b* B$ r; A7 [ set auto? false
" G* E# ?# e3 J ~7 r7 H( J" A set green-light-up? true: X+ B$ x* R9 W
set my-row -1
4 `% q' l9 Q" `6 |$ _: E9 ? set my-column -1
( J4 ^) V3 U9 [2 k! m5 L4 x set my-phase -1
# r1 N) M! S# X) O) e) [4 t" u) h set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets
4 @# _4 J N$ ]0 l' j2 O set roads patches with
I, }" `0 I$ }, Y Y" w; {0 D [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or6 L+ x& B1 O) f# k
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 n; W& _" ^2 E1 B* p: z set intersections roads with" L7 `$ {; w1 E" T5 x# k8 j
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
% J% u* J( C& h) g (floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 x% a6 `, |6 @( m; ]4 w' T
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ask roads [ set pcolor white ]
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end
7 c/ d: `- f9 q, v# }4 J5 c, g其中定义道路的句子,如下所示,是什么意思啊?
# J$ m, M) u+ l9 n set roads patches with
/ N) V. ?" {4 J/ g, o% a( [ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or5 |( V1 Q# e9 E2 |
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 ^1 L y+ h7 B/ W
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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