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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。
, L9 y! O( H' r6 p) hnetlogo自带的social science--traffic grid这一例子当中,3 B$ O; _5 X& C; E- J7 r i o. J& l0 N
globals
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0 ]- k9 M0 k# M/ V0 c grid-x-inc ;; the amount of patches in between two roads in the x direction
% P* V& x' t1 T/ ~5 C3 d grid-y-inc ;; the amount of patches in between two roads in the y direction# S6 A) I2 G/ K
acceleration ;; the constant that controls how much a car speeds up or slows down by if
# @4 `9 ^. Y* y, G1 k ;; it is to accelerate or decelerate
8 z. U+ B) }# W# b/ d8 G phase ;; keeps track of the phase; U8 M: ?) N. C% F* E Q4 C* @
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
$ E7 O: h; Z7 j7 V current-light ;; the currently selected light
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;; patch agentsets9 \0 @+ G$ n ?
intersections ;; agentset containing the patches that are intersections4 F, _9 I& T4 a- l
roads ;; agentset containing the patches that are roads' T4 N3 j) |: Z, E/ H
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8 Z. T0 Q; A9 ?( A: Dturtles-own
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; N0 H/ `& j' o# k speed ;; the speed of the turtle% c6 y5 D: X! \* S2 [! T
up-car? ;; true if the turtle moves downwards and false if it moves to the right
3 F- ]2 ]7 m1 D; { wait-time ;; the amount of time since the last time a turtle has moved
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! `5 m7 M5 B+ y# q$ R# |patches-own
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. G7 A! w' {: r' \* y1 l intersection? ;; true if the patch is at the intersection of two roads
1 J- w- w- t3 w: u green-light-up? ;; true if the green light is above the intersection. otherwise, false.
$ s Y9 s5 g$ f2 s ;; false for a non-intersection patches.. i, ?2 E" H) `( n0 o
my-row ;; the row of the intersection counting from the upper left corner of the
# h3 h2 R9 s9 Y" ^8 x' e( @ ;; world. -1 for non-intersection patches.
3 j/ Y: C. o& P& d6 s8 z my-column ;; the column of the intersection counting from the upper left corner of the
5 y$ V* P+ P0 \! |4 u ;; world. -1 for non-intersection patches.
, N3 ]: D; v. C my-phase ;; the phase for the intersection. -1 for non-intersection patches.
, V1 C) W" p! v! c& k auto? ;; whether or not this intersection will switch automatically.
: A) V1 _' C& ^& M; \. M S$ Y, h! R ;; false for non-intersection patches.& F& a' p' ^. Z9 @
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;;;;;;;;;;;;;;;;;;;;;;% @2 w) x2 t- K) c$ @4 x
;; Setup Procedures ;;
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% s! h6 h, l4 w) @;; Initialize the display by giving the global and patch variables initial values." r' }6 G/ a0 G. \6 b* j" i2 f
;; Create num-cars of turtles if there are enough road patches for one turtle to1 I. w8 ]6 Z6 Z0 p
;; be created per road patch. Set up the plots.
b4 ~# x' y+ u! k" c4 Hto setup: G4 t9 Q. n- H3 g/ J$ ]
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setup-globals- f+ q2 O+ C/ m
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;; First we ask the patches to draw themselves and set up a few variables$ T; m' k9 a4 d4 u- v$ t
setup-patches4 k" W$ t3 e" [
make-current one-of intersections
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% N; Q$ D5 a3 R! ? set-default-shape turtles "car"8 p; O; K: ^. F: P9 p& m
1 `2 w5 O" o% `' t6 L/ i5 Y: W- f @ if (num-cars > count roads)
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# r! W' G/ t2 w: L! i user-message (word "There are too many cars for the amount of "8 z- a# q2 i: s* U5 b
"road. Either increase the amount of roads "
. V8 e. ]0 D0 a% t8 s: F. ` _ "by increasing the GRID-SIZE-X or "
6 \" f- m" d/ M# e! K& _# k* p "GRID-SIZE-Y sliders, or decrease the "& Z* L9 h3 k) }
"number of cars by lowering the NUMBER slider.\n"
/ h& l* b, K8 l J3 i "The setup has stopped.")5 _1 o M0 V/ l& N* Q0 x' K
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
$ ]1 I% n( q7 i" S; G crt num-cars9 Q' ?& }$ w& s+ C( X
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6 ?2 p/ S8 Q1 A! u8 o* z" U2 b setup-cars. O* G* }9 U: ~0 F c
set-car-color- e4 j1 }; W% R0 j
record-data. Q+ @; l2 x, r7 x
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, C% C4 n4 M0 Z7 m ;; give the turtles an initial speed
' e i% ~( f4 \& a7 t- h ask turtles [ set-car-speed ]
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0 q/ c1 u; t" b. s- u+ k" G reset-ticks6 r- T! a+ F* [5 O {
end
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# i) I8 p9 L4 S* }) M0 o$ };; Initialize the global variables to appropriate values
- u8 s& N- q2 _. b" C3 b+ @" N3 Uto setup-globals# R4 J& p1 w. I# F' ]3 P+ F l( R
set current-light nobody ;; just for now, since there are no lights yet
4 d, D: C2 Y. x7 U. } set phase 0% t& n( l, F3 s9 C# t
set num-cars-stopped 0! ?; B) X; g5 B
set grid-x-inc world-width / grid-size-x
1 A8 N( d& L: B; [& m9 X set grid-y-inc world-height / grid-size-y
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, v; Z7 g9 P& @& p. U$ x ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
& ~8 i, F" }( Y a$ ^ set acceleration 0.099) B7 P+ S8 z8 f" y" v7 v$ X
end0 c3 V3 x! ]# G! a7 I6 L
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,( F* C+ \$ t! Z+ u
;; and initialize the traffic lights to one setting
" R) D0 O( y& |, |* W0 W" I" s5 Vto setup-patches
$ v1 P; o# Q }1 Y/ y ;; initialize the patch-owned variables and color the patches to a base-color
v' [- `7 }+ R0 m4 ~8 Y" a ask patches% b: z8 l8 J2 s) l
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% D: d7 ^0 t0 c9 E) x set intersection? false
7 ~$ D; Y5 W% d g% Z, c1 b set auto? false
( u; m. A0 d) u0 @4 Z: N0 k set green-light-up? true
3 l: Y, t& B( S' G- m set my-row -1
0 l4 y5 z7 r& Z, t& x' L7 Y set my-column -1
7 y! \5 j3 h% M1 J* c) z7 G& S set my-phase -1
; n9 h% Q: z" Z# d8 U2 W set pcolor brown + 3
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6 i9 X& m7 Y, L3 ?' J ;; initialize the global variables that hold patch agentsets
; l+ \8 j3 p# L set roads patches with
; }1 r0 F4 [3 I4 _; ?0 s$ ` [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- } @8 m# g3 y$ K+ f7 z
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# F$ A0 G) _' ~7 E0 Z' {
set intersections roads with
. Z6 V5 p1 T- r6 I: J [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and% O' C Z; n# m3 O! O! d& Z, Q; p
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]. u0 n9 c% S" u5 {6 I
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ask roads [ set pcolor white ]
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end4 y9 N; h& R/ ?! n* v
其中定义道路的句子,如下所示,是什么意思啊?! Z ]+ b8 V$ T9 d( ?) z
set roads patches with
% G1 `/ \, i* Y: Z( [3 P [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
- F8 X' _+ p4 c T' U2 S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
' A$ n0 ?. c0 u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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