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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。
% S. ]; |# i: X8 m& R lnetlogo自带的social science--traffic grid这一例子当中,
" h0 F8 t, _1 @& Xglobals
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! G6 s8 l) U+ H5 d8 K& A4 n grid-x-inc ;; the amount of patches in between two roads in the x direction
4 G/ e S8 X. {4 z8 L; z; z grid-y-inc ;; the amount of patches in between two roads in the y direction
6 o4 ?+ ^' e2 k8 ?1 M! m; C acceleration ;; the constant that controls how much a car speeds up or slows down by if+ q5 `% \2 O4 H; B ^8 Z! R* B( |& |
;; it is to accelerate or decelerate
1 n+ W) Z' p# o0 x6 n1 J phase ;; keeps track of the phase
& R; t; ~- \: p( m num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure+ P; X) r: _0 q/ M8 b' ?' e
current-light ;; the currently selected light
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9 d$ T3 U2 L3 h, l" F; S ;; patch agentsets
8 |9 t8 b4 s3 h2 w4 l" L2 w+ H intersections ;; agentset containing the patches that are intersections
( `( V& Z& s, [# @& a9 ^( d) h roads ;; agentset containing the patches that are roads7 q R! l* z& i+ h
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turtles-own% T' l' t$ ^/ W' g$ v, ^
[
6 L9 m9 x( f& S- L+ g speed ;; the speed of the turtle9 }7 `: I! l0 g8 z S4 f8 D; _+ {% ?, G
up-car? ;; true if the turtle moves downwards and false if it moves to the right) A3 D$ N" u8 @; {, i
wait-time ;; the amount of time since the last time a turtle has moved$ B7 R& E0 y* H) I& h; f: Z
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
! `( o& L. \, a; {; }! T- l green-light-up? ;; true if the green light is above the intersection. otherwise, false.
8 h4 Z9 C4 L, ~/ \5 i+ N) j ;; false for a non-intersection patches.! ^4 \3 F6 n4 n2 @1 L2 z4 d4 C7 Z
my-row ;; the row of the intersection counting from the upper left corner of the7 c. H0 \2 U7 W6 `
;; world. -1 for non-intersection patches.
) t2 p: e! I/ a my-column ;; the column of the intersection counting from the upper left corner of the
7 ]0 }3 f: H# V% t5 P ;; world. -1 for non-intersection patches.
; F- {7 o d U T+ p) a9 `/ U0 N# f my-phase ;; the phase for the intersection. -1 for non-intersection patches.
1 j) o8 g$ M9 a, P auto? ;; whether or not this intersection will switch automatically.
" k7 i l. q* G ;; false for non-intersection patches.. S8 y2 k0 L5 W) p9 ?. R) f" O
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# Q4 [8 H0 o! ` z! v) O H;;;;;;;;;;;;;;;;;;;;;;
/ F* n, r! e, W" Z8 w7 q/ b;; Setup Procedures ;;( ^& F) v% U- N/ [$ G9 j
;;;;;;;;;;;;;;;;;;;;;;9 r) @2 L& f" Q' J) ^
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;; Initialize the display by giving the global and patch variables initial values.
6 I! J% ~8 v7 S$ _;; Create num-cars of turtles if there are enough road patches for one turtle to
8 z9 o3 U S4 S& c2 B! V;; be created per road patch. Set up the plots.8 V: m4 P. U$ ?" ~% C S0 A k
to setup/ Q% V3 f) |# b; l7 i4 h3 Q- i0 k# X, ?
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables/ ^ g) ]3 T3 a- }9 k6 V
setup-patches: x% a8 g1 T# R g# N: L d, R
make-current one-of intersections. ~/ c7 g* ^* X3 m8 r, ?6 y( E) `9 G
label-current
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$ s" q# h) ~3 d# C* E. e( O; m set-default-shape turtles "car"
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if (num-cars > count roads)$ d9 F. }5 m- w0 O
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user-message (word "There are too many cars for the amount of ", b/ _) G7 S! d. Y5 J
"road. Either increase the amount of roads "
& s$ l8 H! W9 I& |+ ]$ K5 P "by increasing the GRID-SIZE-X or "" r1 h# ?5 b+ r8 I( \
"GRID-SIZE-Y sliders, or decrease the "
- {& E. X, X& p "number of cars by lowering the NUMBER slider.\n"! r- @4 F, o2 [: i
"The setup has stopped.")
6 k# _# |$ d, {: k, s: `- k; @ stop" ~! N$ U( {- |+ _& ? B0 f
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* ?2 `' Z+ U2 R' r ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
$ }5 u- \! ~) g5 j2 ` crt num-cars
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setup-cars6 C! Z8 T r. E) M6 X1 s$ s( w7 D
set-car-color2 n0 }4 l) H8 R. q4 p
record-data0 K. z. N5 u. Q
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6 i* t: D2 u5 _! ` ;; give the turtles an initial speed
6 x0 B/ X% L7 H ask turtles [ set-car-speed ]
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+ D# Y M g3 _$ s reset-ticks
, l6 P0 [' d8 `; _end, w8 w; b6 U* U8 K; O
1 ` T2 `7 A' w8 N( \7 S- H;; Initialize the global variables to appropriate values
4 O R3 F. {* b$ _1 q7 u2 k3 Gto setup-globals
. z; X; A, Y! C$ H# j! s set current-light nobody ;; just for now, since there are no lights yet1 g3 L5 ]* ~+ d2 d
set phase 08 u5 U# o4 F) l8 c
set num-cars-stopped 00 v" {: u2 W8 q3 O2 u+ S$ i4 x
set grid-x-inc world-width / grid-size-x
; j. l g+ ]) K( Z( o set grid-y-inc world-height / grid-size-y
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- x, m& s m- j% G9 h4 E ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
' e, z% d' \. X7 Q/ a set acceleration 0.099- h- ~0 H( S \
end0 {5 Y! `0 I2 v6 U2 x4 I( K
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
2 |) A* d- b0 i1 r2 E: u* c) h! G;; and initialize the traffic lights to one setting; w+ j& w4 T6 W2 i. b7 F
to setup-patches
# d" f# x, p: o+ a; f( m ;; initialize the patch-owned variables and color the patches to a base-color
' C" E/ u% y" n0 P ask patches
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set intersection? false3 S5 y. h2 s9 H! o
set auto? false
! f3 F0 d. _" e- ]% j; ^! B set green-light-up? true
9 M; q8 I4 {' W. E/ K' o set my-row -1
f5 o2 R9 @9 x( ] set my-column -1
% O$ U9 L. }" ^7 g8 Y, @! l6 _ set my-phase -1; n3 Q' \) F F$ \6 |. g$ t
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets7 g- R2 x9 c# h C' p
set roads patches with2 _7 Q2 l: a" a9 {& o" v
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 K% ~' I. ]) q" Y! J7 f$ R+ O (floor((pycor + max-pycor) mod grid-y-inc) = 0)]/ L" ]$ h. l5 T x1 @$ f- @
set intersections roads with& M$ `$ U* B$ ^( u
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" J7 w& K. X+ m7 Q4 S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]" L5 O( R% j1 N# w8 w9 E- B
( T a- w3 t' j% p1 c ask roads [ set pcolor white ]
3 F0 X" @7 ?9 P: M setup-intersections
9 V6 d6 `; Y, T Cend
, z Q' d+ z" b/ I: {- L其中定义道路的句子,如下所示,是什么意思啊?1 M8 h- L+ V6 E* \ {
set roads patches with6 }! o- }+ K, `! B1 L! T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or o2 z/ D* V# E: q+ w2 n; s
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 C9 B' I( ^1 O; [, p& X+ L7 U1 h, ^
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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