|
|
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。& Z7 F) b+ b! n
netlogo自带的social science--traffic grid这一例子当中,
/ g! h# e) d( ]8 lglobals
/ a, T' I3 z+ ?% ]- U: W$ Z, S( r[
' {" I T! b" o h1 d8 _ grid-x-inc ;; the amount of patches in between two roads in the x direction8 G. p2 `+ U) M* I6 V3 I/ u' |
grid-y-inc ;; the amount of patches in between two roads in the y direction
6 G3 v5 Q8 o( [9 I acceleration ;; the constant that controls how much a car speeds up or slows down by if; T6 H, Q5 x s. p j5 g8 {
;; it is to accelerate or decelerate; N- L2 r3 l+ K A, `, p
phase ;; keeps track of the phase* ^' A+ N& E: F$ m: e0 Z$ ^
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure {) Q$ w! F) e7 N6 k! V
current-light ;; the currently selected light
* @ Q1 _: k! n" g( A$ \4 A+ m& v; |3 C) q6 f+ z+ ~6 i7 d2 @) _
;; patch agentsets
1 u6 \5 `% P M intersections ;; agentset containing the patches that are intersections
m% q3 ], U# M) |& L) L; Z$ i roads ;; agentset containing the patches that are roads
2 {7 T3 Z0 c# W' |8 h" N" Z K]4 Y/ ^; {5 y1 F/ P4 a6 ^$ `# {" g
% K; J6 [0 p3 u4 v5 x9 Aturtles-own, S) u) z' u7 x- A1 ?* S5 Y# W
[) V" }* o5 ?! K* i7 n6 D
speed ;; the speed of the turtle6 M/ t# e& v9 \ l
up-car? ;; true if the turtle moves downwards and false if it moves to the right
2 {' T- Y9 Q9 a1 K: L" Y, \8 F wait-time ;; the amount of time since the last time a turtle has moved
' G; o& |+ V6 E# z]# e5 h7 X# s2 d" N- G, h" v
9 h4 D. z9 E$ f
patches-own7 u1 p4 P# G9 h r2 Z- f
[9 L. ?0 l( C1 q0 b* V
intersection? ;; true if the patch is at the intersection of two roads( ^2 z+ x2 a5 j3 x
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ z3 X8 q9 l3 n5 v$ @( W4 C. | ;; false for a non-intersection patches.
: Z0 P/ B5 k# ]- f. N+ Y my-row ;; the row of the intersection counting from the upper left corner of the
1 d4 W) Z$ v8 c" `6 D+ w% | ;; world. -1 for non-intersection patches.+ T- G% A& ~9 c! ~) H
my-column ;; the column of the intersection counting from the upper left corner of the
8 s! n c# v7 W8 n ;; world. -1 for non-intersection patches.
* u* g6 R5 |! K) ]- R( ?, Y) H. B! @ my-phase ;; the phase for the intersection. -1 for non-intersection patches., c1 E/ }% E7 m/ K
auto? ;; whether or not this intersection will switch automatically.1 W+ K2 X8 a: E0 i* t; O
;; false for non-intersection patches.
/ [+ V* W* m" P. h9 Z]
* s' X- W* G4 Q4 w
# s% B2 ?+ h R2 C: H" E# E2 W+ f# C4 H
;;;;;;;;;;;;;;;;;;;;;;
4 [% s/ F; U+ {, l7 O& k7 x;; Setup Procedures ;;4 F/ u; d+ o9 }& x& z2 | o( u
;;;;;;;;;;;;;;;;;;;;;;
# t- j- e5 [1 k8 K) s) X+ H/ x/ w0 b4 O. j! u4 K: |
;; Initialize the display by giving the global and patch variables initial values.
2 u9 g' S( n- ~1 U" v;; Create num-cars of turtles if there are enough road patches for one turtle to* A. d7 ~6 `: v- S% `- b1 }
;; be created per road patch. Set up the plots., c u, u0 Z0 p5 E& I
to setup3 [/ s" N. r: s
ca0 A" [ ?7 {# `
setup-globals, @" F; }& \& e4 i. M( d
2 H) g7 f0 u3 {* S F& p
;; First we ask the patches to draw themselves and set up a few variables
( M5 h0 L$ f2 D setup-patches3 d0 ]: t. o3 O) Z0 A# T9 ?9 F v# R! H
make-current one-of intersections
0 D& _& s1 O9 A$ B' ?1 [- y label-current
' o7 U9 [/ `, K$ N. Y9 m, g" |' J% x* r
set-default-shape turtles "car"
6 C5 G! @" A3 d1 e6 v8 B* y/ o+ g! C, d$ ~+ z. \5 {
if (num-cars > count roads)
& @; h: H! c5 a! k- W, g) | [
! Z& g$ x2 `7 ?. q user-message (word "There are too many cars for the amount of "
7 w/ W: [2 ^$ s& s" @4 X "road. Either increase the amount of roads "% \9 C- m/ t2 b8 x; ]+ f
"by increasing the GRID-SIZE-X or "
* ?1 Z+ \) j9 f# o9 }- \ "GRID-SIZE-Y sliders, or decrease the "4 V2 E' C2 C. y$ T) ]. @
"number of cars by lowering the NUMBER slider.\n"" |8 q6 j' d0 u! L
"The setup has stopped.")9 R- ^, `+ Z0 @* Q3 X6 s3 G
stop
# G# L2 a% ~7 q ]+ n" \( S. N4 H* }; A e+ ~
@& t! o. ?; {" x1 M7 p ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
- q Z, _: E3 g# c7 t4 S crt num-cars! \) N" ?% {; Y2 K
[
0 R) u( D, P! k; Y4 }, S) [ setup-cars
5 |8 Q) g8 x# M; l+ t set-car-color" }# t0 a7 i& S2 V9 P. \
record-data
; r2 F- C: r1 r4 O4 N5 Y' Z9 A3 { ]
m+ x1 k0 n! l6 `( A
# H- G2 Q" X0 ]# G$ M( X7 ?+ Y ;; give the turtles an initial speed
3 T8 q r% T, j" x9 P1 H ask turtles [ set-car-speed ]" R5 K i8 l: C' x# x. g+ w
. U/ X5 ^3 R8 _1 P$ g! v$ z: k6 x9 b
reset-ticks: |3 r. T3 [- W9 w G- Q, a
end& Q- h8 e- y8 y h, r3 c
' A3 n& }9 y% C# D/ v( r% I# ~/ }
;; Initialize the global variables to appropriate values
) u. ^1 g5 s7 ^; c+ Z- `1 _# J6 Kto setup-globals
4 Q1 ?6 o2 O2 s8 a* K set current-light nobody ;; just for now, since there are no lights yet
6 j. `! t. q! y. P. r set phase 0; D% M5 U3 w1 y$ f. X
set num-cars-stopped 0
* O0 Y! j0 {0 P/ z; @$ F+ Q5 J/ Y set grid-x-inc world-width / grid-size-x
8 D+ G( T( I5 t- N/ N V set grid-y-inc world-height / grid-size-y: T1 o/ t5 b, C6 W& g: ^5 N4 k
, q" }' g" P2 m
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
& D& A# i {, j+ S! a7 ~" u set acceleration 0.099
2 b0 z% O N. N9 J3 v: p/ u% a' Z8 Eend
% l! h. a, U: h9 p
; E4 n" O% F1 s;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 C5 c. ?, O! ]* Y! _
;; and initialize the traffic lights to one setting6 N- O, q6 i; V8 S; }; ^( E
to setup-patches) l. v b! v2 o* k* j/ R* Q
;; initialize the patch-owned variables and color the patches to a base-color
/ y; |9 K6 R0 h, O* d2 s1 q ask patches
$ t8 b) i( X7 F' g! H4 h [ F: D9 N- a: }; z6 J7 I
set intersection? false1 f& ?" x5 T; ~6 s, r" K5 G' `
set auto? false
+ N+ \4 x; F8 ?* {# G3 d8 R% Q set green-light-up? true
: G g9 U+ G1 F! z9 n set my-row -1
) h7 s4 x7 V8 `" e. c% i1 u set my-column -1
( y& U$ m! p' [2 T set my-phase -1
* O q6 a5 j- |; |' s9 X! L set pcolor brown + 3
& V- L! U% @. k E ]
6 ?& A4 K! Y/ I% U9 E3 }8 O" N9 ^9 y+ K9 i! Q8 l
;; initialize the global variables that hold patch agentsets* z. }% {) q9 B3 M) e
set roads patches with3 X% d7 [ u2 m2 B& w3 d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or4 I+ q0 R. f4 [8 R# S' O2 I1 o2 t
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' k+ ~2 R+ b; r+ e* J2 X; Z set intersections roads with. r% f/ {3 U4 w: Y' [- a
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
& F. _2 ]8 ?) j% c6 }/ E$ d (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% O' B C! F4 T' c/ T( v
( V' F0 w; z2 A- W9 w0 k6 t ask roads [ set pcolor white ]/ [: m9 z: X1 Q% D8 g% d
setup-intersections- P& H) g4 B: _) w' e7 j# w1 N
end
/ g/ G: d* I/ E其中定义道路的句子,如下所示,是什么意思啊?7 L4 R# s/ @8 Q( r( G/ y( a j
set roads patches with
# U3 M0 } ?* v' ]' k6 W7 X [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
. a( ?: i& l# \7 g% b+ y" | (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
" W- I$ l$ b: |4 h, ]$ V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? |
|