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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。
) n. @3 ]; Y5 ]$ U& i. Inetlogo自带的social science--traffic grid这一例子当中,
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# n; h8 ~, F0 C ?1 |) }+ a grid-x-inc ;; the amount of patches in between two roads in the x direction) [, f2 V6 o3 I: K3 ^5 t; K$ O
grid-y-inc ;; the amount of patches in between two roads in the y direction: V2 x2 \6 X: [. Y( w
acceleration ;; the constant that controls how much a car speeds up or slows down by if, J% w6 y3 {# p5 n% A6 t% s
;; it is to accelerate or decelerate
% c6 c; ]4 L- ^# m- p8 b phase ;; keeps track of the phase
' @- a8 H: p+ h; `; |- A! R, @ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure g2 b% N& L& D% P
current-light ;; the currently selected light" d% J8 g+ u3 a" u& B
7 c! F v3 G6 [) K* T6 H ;; patch agentsets e3 N- n3 M8 c8 s; Y. O
intersections ;; agentset containing the patches that are intersections
/ C1 o$ }- n2 R roads ;; agentset containing the patches that are roads0 H/ j5 w4 n8 d* f- u. o
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4 P) G1 i Q% p5 f3 ?turtles-own8 i, ?' p L; r3 Z
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speed ;; the speed of the turtle
% B9 @. ^1 T2 v) |# N up-car? ;; true if the turtle moves downwards and false if it moves to the right% O: F3 q8 B: T9 j; h0 D
wait-time ;; the amount of time since the last time a turtle has moved
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1 D' Z% c5 W% G8 M1 ]patches-own
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intersection? ;; true if the patch is at the intersection of two roads. L3 Y* m$ k6 T
green-light-up? ;; true if the green light is above the intersection. otherwise, false.6 E0 k4 \% t0 U% ^) N G
;; false for a non-intersection patches.6 S) \! k7 U% b7 \
my-row ;; the row of the intersection counting from the upper left corner of the1 F+ \6 k0 @4 v8 [: q
;; world. -1 for non-intersection patches.
+ R# M0 P% r9 Q, {; Q my-column ;; the column of the intersection counting from the upper left corner of the3 B3 x% d& h2 ~2 p
;; world. -1 for non-intersection patches.; V {4 F3 @5 l" g* X+ u; Y
my-phase ;; the phase for the intersection. -1 for non-intersection patches." j& i2 b8 U9 Y) i/ X
auto? ;; whether or not this intersection will switch automatically.! F( T: ]; F( q2 y$ k5 H
;; false for non-intersection patches.7 { y2 J8 s h( x. c1 }( b
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. E% g! }' t: L8 N$ E;;;;;;;;;;;;;;;;;;;;;;: K1 e1 ~7 ^+ I9 o
;; Setup Procedures ;;
7 w* Y, ~: s7 d: B6 w- s;;;;;;;;;;;;;;;;;;;;;;
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/ G! a5 u& O" f;; Initialize the display by giving the global and patch variables initial values.' _7 w+ ^" T) R" r8 O; ^
;; Create num-cars of turtles if there are enough road patches for one turtle to3 \+ g$ M5 D v4 E6 D
;; be created per road patch. Set up the plots.& F4 N8 q( P0 E; m
to setup
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3 Z3 n% H( l6 n$ A! A% W% h setup-globals
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! l+ c& [1 s) o5 N" l) G. X) v ;; First we ask the patches to draw themselves and set up a few variables9 k8 K7 q- q! I% w
setup-patches
9 P/ d5 S3 l6 [- B4 U: I$ h( ] make-current one-of intersections
+ e8 [+ p n6 d; j label-current
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( X# i) g, {( S$ q( p8 T set-default-shape turtles "car"
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2 F1 J2 W3 t4 M! `7 u if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "9 u9 B+ V& c$ f2 s
"road. Either increase the amount of roads "# x, |! y% q! f: L
"by increasing the GRID-SIZE-X or "
, m6 G% ^: g$ \& r8 n "GRID-SIZE-Y sliders, or decrease the "
. R7 V | ?6 ^ b" K: u3 @ "number of cars by lowering the NUMBER slider.\n"
* E% h8 [2 X9 O. o+ K" k+ i "The setup has stopped.")
5 A' ~- j Z$ |9 {2 L6 b0 ? stop; Y& w; `. ^) L! e5 d7 Y
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8 N( Z/ _* V/ ~2 r2 G" Q ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color+ S3 ?9 f1 e. G0 }& G1 ~
crt num-cars
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setup-cars
8 ]4 n4 _; `2 C set-car-color
9 a$ h* j5 }3 l, r' H record-data
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;; give the turtles an initial speed: K7 O. o" |/ H' E% M' Z
ask turtles [ set-car-speed ]# S H7 \ P# K1 k; y L! ?
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reset-ticks% T5 S; F# i: i/ b) i Z- O" B
end) o+ V, O/ U' ^# K( _
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;; Initialize the global variables to appropriate values4 _ Z: F {$ ~, z' z
to setup-globals# N3 R2 g: h& I! [) {0 P
set current-light nobody ;; just for now, since there are no lights yet! k* U r) S* \. N5 ^
set phase 04 C$ x S2 b$ N) t3 m4 b, p3 K
set num-cars-stopped 0
# C% x2 _+ s7 h! u set grid-x-inc world-width / grid-size-x
# x8 N) b0 s! S/ t& m 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
- R4 z8 }4 n2 W set acceleration 0.099
7 X8 Z' k3 s0 uend
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1 g3 N- X9 z9 a/ Q% T# Z$ c;; Make the patches have appropriate colors, set up the roads and intersections agentsets,: _ W8 O' k/ a' u F0 R( n8 A
;; and initialize the traffic lights to one setting
6 X1 b* b7 x" i( F% E; K5 Gto setup-patches. W7 ^- U- t4 `# k* G& c
;; initialize the patch-owned variables and color the patches to a base-color
- ^* J0 |2 g" M' a) S ask patches" Y) w" | T* n1 `6 |
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9 f9 g8 k0 a3 T# P$ o' @& |) n set intersection? false
( b- j7 y: g( n5 f; { set auto? false
! C& ~/ h$ P7 N" j, p- V" i set green-light-up? true1 \1 b: ^" W' E1 t0 v# z
set my-row -1
' v V1 W( i. {$ F0 F set my-column -1
( T1 o/ d% T. c$ p& z* w* ?8 L set my-phase -1
4 A- ~) O( ^: A9 i% O m set pcolor brown + 3
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- H9 I' N5 D& C8 H4 V ;; initialize the global variables that hold patch agentsets
8 c: K% }& }( ]3 t K7 O set roads patches with
6 \3 W7 |/ P2 X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
% Q& |, C; J" N (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ h6 l `; W N& U1 P( U& N
set intersections roads with
8 o+ v" U0 Y H" b9 z3 e [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
) z5 f3 M! `% a (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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: P/ ]# C6 X: ? m ask roads [ set pcolor white ]% h! N. m- y% a
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
/ l4 i8 G9 I3 d0 O' }. F set roads patches with
6 l3 A- Z0 Y4 d6 G( L/ n" V- z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or; u' i. c& Q; n) J' @, L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]* {: k1 v2 B. {# Z0 k
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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