|
|
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。
1 X2 F% n% S, ]( F Z7 Znetlogo自带的social science--traffic grid这一例子当中,
; K0 S: F: ^4 p, n4 oglobals
. C$ z* @, v; s4 ]; L7 b' |[2 \% o+ \. g3 p
grid-x-inc ;; the amount of patches in between two roads in the x direction
* I- M' Z, j; t* c4 Z4 n grid-y-inc ;; the amount of patches in between two roads in the y direction
2 f( s: T2 v1 p$ S( Z acceleration ;; the constant that controls how much a car speeds up or slows down by if( ]$ u2 i5 |, p6 w! a
;; it is to accelerate or decelerate: D2 a% N) T4 }
phase ;; keeps track of the phase
/ L% Z. {9 p0 \7 ^6 I% R num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
' Z" y6 s+ I5 C& }4 o: A current-light ;; the currently selected light
2 w! [% P: o" B5 S4 I. ?9 Z+ |) H7 v
9 C, b7 E, p# V* J4 d( L ;; patch agentsets" R4 j6 j" O% [0 W$ }
intersections ;; agentset containing the patches that are intersections- k2 [4 |2 Y, [3 g! c m) Q! N
roads ;; agentset containing the patches that are roads6 e: U/ f2 `; j3 A' Q0 l
]
: q& T' G- R- I) J) z {% c7 `$ P" H3 R8 p+ e. w0 p
turtles-own
/ ^ y; M; y5 s7 f( {[: U5 d2 Y) E- c8 G; K- b
speed ;; the speed of the turtle* u8 L9 o4 E- e7 N* `- B
up-car? ;; true if the turtle moves downwards and false if it moves to the right% n% b, `0 F* v& b: q1 E9 V
wait-time ;; the amount of time since the last time a turtle has moved4 l) B* Y4 z5 H. }( `
]& A6 f# q" u/ l. h7 E6 t; K2 h! p# A
* W( h- Z/ c9 C' j; Q
patches-own- g$ i; u3 |" V) E. y
[
( g/ p* J, n% ~5 p, y intersection? ;; true if the patch is at the intersection of two roads6 j3 |( }8 ?$ K7 o' V( y d% C8 P* i% a
green-light-up? ;; true if the green light is above the intersection. otherwise, false.2 I9 b! R# q" i0 v; s0 E
;; false for a non-intersection patches.
& _7 _, j# h' | my-row ;; the row of the intersection counting from the upper left corner of the6 d% R+ L& A7 G% D' a
;; world. -1 for non-intersection patches.3 i: w) q' u6 N+ F9 z- {7 i
my-column ;; the column of the intersection counting from the upper left corner of the
+ c: O' o, `" ?& H# _ ;; world. -1 for non-intersection patches. [9 e9 ?& c0 F6 f" o
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
8 ^- {# Y. e" A. D6 A( v- J, [2 ] auto? ;; whether or not this intersection will switch automatically.
5 Z# v& Z) f4 r' Q. P, K ;; false for non-intersection patches.
' |0 J/ |9 S; T: X6 f; x) l], u: f, i [; b# a. z9 T
; o" U6 m$ T% A4 x* {
; w' R9 P0 U% N5 G$ G/ U;;;;;;;;;;;;;;;;;;;;;;# C$ j5 I+ |1 z& W& i' z
;; Setup Procedures ;;
% | S% A/ V& k% N5 w) S: r;;;;;;;;;;;;;;;;;;;;;;) Y F' e' P$ ]$ Z3 p4 n7 a( B
+ Y( F9 W3 K4 J$ i;; Initialize the display by giving the global and patch variables initial values.# F; a5 f9 K5 s3 `1 q4 x
;; Create num-cars of turtles if there are enough road patches for one turtle to
/ u7 m8 a2 C; p+ L0 ~" }4 }# E0 X;; be created per road patch. Set up the plots.) {. K. H# J. ?, o' ~% R
to setup& V' ]. E" _" O2 `5 A+ W/ R
ca
& f5 ?$ V) [" Y* S setup-globals; a% L. F7 Z, i$ v2 J' `5 R
" L0 b( {: P& _, Q' g+ v# {
;; First we ask the patches to draw themselves and set up a few variables% T' L, c1 ?1 J4 c6 m- \
setup-patches9 x$ k8 K! K7 a
make-current one-of intersections
9 K8 j* p' \& V2 S7 O% G8 Y label-current
1 t& R- w. z, i1 y& K+ a! l9 C4 Y6 K( |, _; \/ v& J/ ?: X. j
set-default-shape turtles "car"; P3 a0 Q( u' }
( g) t$ O/ h$ e! y" W* J3 o if (num-cars > count roads)
8 O( u2 x' o1 ]9 z- [ [' [: O9 h$ J! J3 @ u
user-message (word "There are too many cars for the amount of "
. z7 K+ ~3 g. V1 Q$ c1 X "road. Either increase the amount of roads "9 Q& \/ [5 x X0 z! ~# i- @
"by increasing the GRID-SIZE-X or "
0 a- x, }! R& m, P* i+ x; W "GRID-SIZE-Y sliders, or decrease the "! W& I4 T! M5 U% E
"number of cars by lowering the NUMBER slider.\n"
/ J/ l! T! S4 V/ O4 Q "The setup has stopped.")
' T+ [% h) ^' P9 c: _ stop! ? ?2 s6 U6 N: b& t
]
5 Z+ K$ Y7 D8 b1 R7 U- t# i+ ^8 A8 i- R7 a# i
;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color. k, W2 W- W2 T8 \
crt num-cars9 p2 s& W9 F" a
[
! B$ R' u8 V. [+ J# o+ Z3 G( X setup-cars/ ~& k/ }0 R7 b! M
set-car-color
2 a4 C* j0 v& `5 l9 v record-data, e1 I7 n7 h. Q9 C
], u: B) Z' E2 v( j" O
5 ?3 C; \6 p! X' q. q2 P ;; give the turtles an initial speed
0 p! t5 G- W# {, O& A8 J% i H' [ ask turtles [ set-car-speed ]
& n) R5 W/ L" N3 r, k7 g, H L- ^6 v& l! y6 F
reset-ticks: q' l; l. B) D* O) t! J; _
end( l. G; c2 K i- G6 ^" X& U a
( P) s, f+ r5 i' ~;; Initialize the global variables to appropriate values- P2 C9 p8 y) X( ^% q
to setup-globals
5 V6 z3 l2 x. n1 }4 a4 F/ g set current-light nobody ;; just for now, since there are no lights yet6 b1 ~9 D" @/ p: x' g# S u* h7 k
set phase 03 r* Q0 u+ c$ A( h$ Z/ }
set num-cars-stopped 0
) \1 K: r! H/ A set grid-x-inc world-width / grid-size-x
6 x U) W& f: J, P4 s. p set grid-y-inc world-height / grid-size-y
' T$ b, Q2 v3 h( ~) W4 I D4 ^" i& i. A
;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
- `, {5 C0 d: ` set acceleration 0.099) }3 a4 m& L+ g, k: S1 X/ o
end
; k) |) K( W* [8 X$ m% ?: k. K
# s# G* `. t$ e; j9 Y. s;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 B& C9 O( `% S/ O' D" n$ q- d
;; and initialize the traffic lights to one setting
: H6 [' ]2 X+ d1 t8 z7 d0 `to setup-patches: _. x" S; g2 v$ s/ ?4 x% h0 }
;; initialize the patch-owned variables and color the patches to a base-color
2 V3 P g: S [* B* G ask patches$ {2 Z b2 n; I G
[- ?3 j Z9 U* B8 Z& ^1 U$ x
set intersection? false
. q+ z/ P$ h- I+ w9 }! }$ R set auto? false3 z. \" ]5 z2 s6 w4 Q: j
set green-light-up? true6 R, [: N; T8 q1 o1 L
set my-row -1: T4 ~+ p _2 d C3 `' T6 z: `: A
set my-column -1
/ i0 T4 \8 J/ l( [ set my-phase -1- B- [9 G7 A' u
set pcolor brown + 3
) O+ H& M( ?5 Y$ c; M+ V ]
3 f; q2 N1 t2 F8 M' |
8 _) f. M5 t) ?' r0 t: E ;; initialize the global variables that hold patch agentsets1 W, Y" z; e' G( c2 B/ n
set roads patches with3 e9 r! l" W2 Y0 E+ ?& A
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or. |9 c8 _& m3 i, H. X1 K0 v
(floor((pycor + max-pycor) mod grid-y-inc) = 0)] g: j% z$ W) F# B N" U
set intersections roads with* a& Z l" @8 n4 _% @
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
+ `/ X1 i1 }: d/ u! c (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
! y u4 ~" A. H8 e2 n- N4 ~1 C7 {
% \; h& I- N: m6 E( Q7 Q5 h ask roads [ set pcolor white ]+ V. {3 K2 \, D% S' h
setup-intersections6 Z2 A) n5 W9 ~0 k0 O' ?
end, o0 s! ]. s' f' T$ K
其中定义道路的句子,如下所示,是什么意思啊?
! P7 r' h; L3 S) A set roads patches with
6 d" Y4 W) g2 I( W, X7 `' ~ [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
& x% p6 l: |. v0 b, E7 y; K* a+ b (floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 M2 P6 A7 d" d% t
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? |
|