|
|
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。
( {& I" D+ b; L( x! F3 pnetlogo自带的social science--traffic grid这一例子当中,
" n0 V$ R7 h# ]6 L a" kglobals2 I" b& p2 g5 D& z( a
[
2 W4 W* v1 M% ]# ?0 J' ]+ T grid-x-inc ;; the amount of patches in between two roads in the x direction, g' g% V9 J; J0 m5 E2 [
grid-y-inc ;; the amount of patches in between two roads in the y direction
( v% _& V* }4 ~: U0 |) C- I acceleration ;; the constant that controls how much a car speeds up or slows down by if
% S/ h5 o+ s& ]) ]% j5 t' L ;; it is to accelerate or decelerate
' C( Y: R* v" C0 D+ k phase ;; keeps track of the phase
& ^( t- @; Y- w n num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure; `6 W3 ^3 v0 h4 y5 d
current-light ;; the currently selected light
* z6 \* x x3 B' D* C
: P0 w0 m, {3 D: [# { ;; patch agentsets
# m1 v1 S, y) C! j( m$ U5 `5 x intersections ;; agentset containing the patches that are intersections
9 y! }2 F* O* r m4 y: q! J roads ;; agentset containing the patches that are roads
9 C J! l) e8 N]+ X' a" c8 N: p# y- R0 [# K: [/ k
/ J O7 _: D! D4 x4 e, m
turtles-own; b: b5 T* L v
[
! Q7 N+ y9 j V \ g& _( i speed ;; the speed of the turtle* e! Y* \& H) K: b0 ~* n/ w; [
up-car? ;; true if the turtle moves downwards and false if it moves to the right/ ?3 u: _$ K6 N
wait-time ;; the amount of time since the last time a turtle has moved; s* y& [4 G6 Z# x2 \+ e
]6 G1 V% X0 O7 v9 I3 [7 B7 Q5 A8 p4 Z
/ g: W! v" R9 p$ _% I ^patches-own: }: a" E* g% L% V. X
[
$ k% I. ]! j' }' V4 i intersection? ;; true if the patch is at the intersection of two roads$ |7 X* F' W5 t9 n5 Z; ]
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
$ W7 z. `+ D3 _# o ;; false for a non-intersection patches.
% p$ u; V/ O8 B+ B8 ?. ^ my-row ;; the row of the intersection counting from the upper left corner of the
" E4 w) P1 ^7 g1 J ;; world. -1 for non-intersection patches.
! ]% s+ j' M Q/ ^+ f; q my-column ;; the column of the intersection counting from the upper left corner of the6 U i! R* ^9 j0 {( y7 x
;; world. -1 for non-intersection patches.
% z' Z2 U5 C l my-phase ;; the phase for the intersection. -1 for non-intersection patches." x/ E4 i. _; V7 q, a3 r( ^/ e
auto? ;; whether or not this intersection will switch automatically.
) B, ` H' t6 o0 B1 L ;; false for non-intersection patches.- K( X( Q, a; _1 h* v
]; b" o# q8 u2 c8 @
. \3 {6 S0 S, m
; Q/ L5 h1 ]# v% Q1 h8 Y, E;;;;;;;;;;;;;;;;;;;;;;
F7 `# f- M$ s% J7 l;; Setup Procedures ;;/ C# b8 R2 K# y# Z2 q
;;;;;;;;;;;;;;;;;;;;;;# ~" m M$ X" J% @* M8 c
) M5 p& z+ y" r;; Initialize the display by giving the global and patch variables initial values.8 D+ p6 s& M+ {/ @' A- O
;; Create num-cars of turtles if there are enough road patches for one turtle to
. y S4 x* A, \. {;; be created per road patch. Set up the plots.
0 k# P% ^$ |7 i, U: V9 y) [to setup/ E/ n! n) k/ \: R; ]
ca
; p4 ?/ o" I1 E- H! { setup-globals
. B0 D' ?. R' B5 S; Y7 M: v1 r, q& [
, R) Y% M+ X* w' J% R ;; First we ask the patches to draw themselves and set up a few variables! m; t5 n9 v# ]# T& i d _( V
setup-patches0 V& R9 \; P. V3 X$ t' y
make-current one-of intersections
# e& k' g# M: D- @7 G label-current
5 _. _# @( G5 V$ f; X/ f2 R- I) X E) K6 Y& ^9 C( M/ Z% n' s
set-default-shape turtles "car"
9 e6 @: F' y" o; n! G- ^- e
2 I1 l- N& a' Z6 ]# F/ j if (num-cars > count roads). l: M/ P! F3 X
[/ t. p. m3 d" u- }5 Y4 {
user-message (word "There are too many cars for the amount of ". ^3 w* X; L* e! t2 v; z
"road. Either increase the amount of roads "2 t) `2 m A# s2 f- d' x, ]% y
"by increasing the GRID-SIZE-X or "
/ L4 d2 e; j* U8 [3 _' B# _% q "GRID-SIZE-Y sliders, or decrease the ". Q, Y* L9 q, h* Y3 `
"number of cars by lowering the NUMBER slider.\n"+ X* ?5 _0 r- B1 u0 [. p% v
"The setup has stopped.")8 S8 ]* T! c7 i) f/ `* S7 `1 ^
stop
2 R0 v! U9 i* M( I. W0 q8 h ]
1 S5 Q# [) T3 v$ e5 Q0 f a3 U3 ^% l- w5 f2 I8 V1 p
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
% l' k. s( D0 A8 n3 P, l2 |' ?, u crt num-cars& ~: l3 L4 G" o5 B
[" ]' {+ A' d' a
setup-cars
7 J2 {" o2 ?, w' y/ `7 G" s set-car-color' Y( [" B, X) Z3 M' `+ s! @3 v
record-data- \7 H3 w" e! c S+ {1 }7 u
]6 v2 { N4 |$ x" v7 v# K
& l; F8 l& |3 M$ j; I- w
;; give the turtles an initial speed
& O4 {* O+ b e5 \( x8 A ask turtles [ set-car-speed ]
T% X, i3 \$ o# W: [! R; x6 c, T+ e1 C+ {" L* q! V/ s
reset-ticks4 z; p# g! ?, o& c4 `7 V
end
/ h- L( m w2 ?/ R: p' A! G8 ~ _; q1 s. e# a2 U6 E/ Q" K' {9 h
;; Initialize the global variables to appropriate values
7 X# Z3 M) M u: P4 ?0 U: o# cto setup-globals
i( L; m; V9 N7 [% \. o: R set current-light nobody ;; just for now, since there are no lights yet5 X, A& W1 Q/ P/ f4 s3 N, ]! C
set phase 0
8 T7 C$ W/ H- } set num-cars-stopped 0
5 M! Z8 z, W4 L set grid-x-inc world-width / grid-size-x
1 X9 _; U- G5 A9 ^* A F8 m5 t set grid-y-inc world-height / grid-size-y6 i# U( B/ V D! }& P. f! m; b# E
# ], A4 h I6 F ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary2 _* \+ G( D: { W5 H
set acceleration 0.099
1 D; j; o; O! ~, x" d! a9 P9 [end, j9 |& g; Q- i. A+ n; _
0 Y0 h [9 [5 m0 \
;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
0 f0 n# W1 @' d9 |4 s;; and initialize the traffic lights to one setting
) j( [8 x2 s, Fto setup-patches
( n) D9 V5 s. {1 F, H ;; initialize the patch-owned variables and color the patches to a base-color
( {% h5 h$ z. b, V4 T( h, ~ ask patches
+ i2 }0 q: N o2 i; U [# w' E3 s8 [% a' w% z
set intersection? false
9 M1 U' d8 a- h- Y0 C+ y set auto? false
6 h* q, a' [. L% v. }" n9 l+ e set green-light-up? true, e' V- T# }" m
set my-row -14 ]% k g: A8 h1 D/ o
set my-column -1
4 I- B7 D/ ^: H1 i set my-phase -14 g, C7 W! _4 n1 e: F
set pcolor brown + 3
+ {( \. K) Q- l9 N0 [1 c2 x ]* }+ ~! [ R. d
, w/ U g3 x8 J; d ;; initialize the global variables that hold patch agentsets
4 l: w- F+ D" e2 D1 k set roads patches with
E6 {, T- j/ n$ d+ p [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or/ B# x! L3 a# c
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 o% `- A8 u" Y3 l4 r6 s set intersections roads with
. _1 V1 J" P7 }8 X; a [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and. T) O8 b% y) k
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]' d$ t" O6 ~' a1 ]. q% s7 C, E
6 g2 p) U1 l% P. _6 o `) t4 ^: q
ask roads [ set pcolor white ]
% I+ r& u' k( U2 o: R, u' x9 a setup-intersections
1 ~7 [7 g1 q4 F- G, h+ u0 l" Pend
, H1 i' B, V9 }- K, c) l8 d其中定义道路的句子,如下所示,是什么意思啊?
; D3 F# N; b% m6 Q$ y! | set roads patches with
/ L' ^4 I! W2 a4 A/ `( N3 ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
( u6 F3 C2 w2 Y" D1 r) p (floor((pycor + max-pycor) mod grid-y-inc) = 0)]! j5 ?$ Y" j+ M, e/ N3 s- J
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? |
|