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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。. U: n6 C4 W7 @! Z( t$ Y% {7 s
netlogo自带的social science--traffic grid这一例子当中,; q: F1 \6 ~* [: I; h, w2 C
globals! d- w; A; Q6 l& D7 q
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grid-x-inc ;; the amount of patches in between two roads in the x direction
2 F7 s+ e9 t5 P) o! m grid-y-inc ;; the amount of patches in between two roads in the y direction( F! X8 Z7 E. {. D2 }0 h3 y
acceleration ;; the constant that controls how much a car speeds up or slows down by if7 m( b6 @, T( B; P' s9 p. i
;; it is to accelerate or decelerate b2 @- l; O$ g8 a3 ^* A. D
phase ;; keeps track of the phase
4 f @& P Z) U4 k$ q% f num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
4 H7 q& `+ a$ _, t) @: \ current-light ;; the currently selected light& i& w8 r1 u0 w }
0 `2 V' Y7 `3 m; V" t4 g2 ~ ;; patch agentsets- G) W1 p! m; M; ]% M9 V
intersections ;; agentset containing the patches that are intersections9 n) n% l6 b" c' m- T
roads ;; agentset containing the patches that are roads" c* i; Q/ P+ k1 K1 F/ B1 t+ ^
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turtles-own
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speed ;; the speed of the turtle
+ y; C) u. z: R. F" c+ @ \+ U& m up-car? ;; true if the turtle moves downwards and false if it moves to the right4 F0 Y1 V0 K% Z) z) D9 q
wait-time ;; the amount of time since the last time a turtle has moved/ ]. L0 ]% Y+ I5 T( X1 K1 }" \
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! k/ y9 h8 g5 T3 Jpatches-own" H D& _" m' m
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7 g4 y- f9 Q8 ` intersection? ;; true if the patch is at the intersection of two roads5 Y0 \! M6 ]; I- [& @& a7 C" K- P6 Z
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- }( i" g: W( h$ k7 a ;; false for a non-intersection patches.6 a2 B0 f: j3 k* L2 I, M
my-row ;; the row of the intersection counting from the upper left corner of the
- F; P' ^( P- E+ Y1 k ;; world. -1 for non-intersection patches.
' A2 ? M2 p! Y) j' q' ]5 C* u my-column ;; the column of the intersection counting from the upper left corner of the a5 U3 b$ L2 y A0 F/ d# i8 f
;; world. -1 for non-intersection patches./ W8 r! n" B8 t, c! f
my-phase ;; the phase for the intersection. -1 for non-intersection patches.2 r0 F5 Y. w" S+ c9 a8 `0 x1 K
auto? ;; whether or not this intersection will switch automatically.
) v9 Y/ b. y/ Y+ z9 O- f- J ;; false for non-intersection patches.
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1 |2 d" G* I2 f& z/ Z9 O8 K# v( z;;;;;;;;;;;;;;;;;;;;;;5 j( _) G9 d$ m# O
;; Setup Procedures ;;
7 x& X) s4 D1 ?;;;;;;;;;;;;;;;;;;;;;;
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;; Initialize the display by giving the global and patch variables initial values.% }0 [1 j# Z) b; n& _9 Q
;; Create num-cars of turtles if there are enough road patches for one turtle to
: ~" B3 p8 c/ j$ ~;; be created per road patch. Set up the plots.
* i0 Y6 `4 d s- f0 hto setup
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3 B$ ]: ?9 t! t' ? setup-globals6 p" k3 F7 T( O& ?$ W
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;; First we ask the patches to draw themselves and set up a few variables
% Y* G* | `7 t( n: Z setup-patches. I* T) ^- C$ ^
make-current one-of intersections/ g; K2 V; f/ u: z+ G
label-current h) i3 B& i- G) o6 h- W4 V: A
8 K9 g# {; n& P8 y! W2 {: S) T set-default-shape turtles "car"
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3 u; O1 t8 d N if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
. s- ?' g- t" T- t "road. Either increase the amount of roads "
+ W' w. s' f5 ]+ d "by increasing the GRID-SIZE-X or "7 \4 j# o0 h- X) _5 U; m- j
"GRID-SIZE-Y sliders, or decrease the "
- i; ?1 e8 S2 v, I/ M6 i6 V- | "number of cars by lowering the NUMBER slider.\n"' l3 G2 R, l3 g, H" F& e Y
"The setup has stopped."), Y+ S- P( [5 T/ l: d
stop' G% @& j1 e( C$ ?
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, g* u: @% b; b/ ~ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
+ T- z- g& a; } crt num-cars
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setup-cars
1 v9 t2 f: q3 W! ^ set-car-color
0 @$ O l* ~) t" r9 J record-data3 t- C {' s+ o$ u7 {; i2 }5 A3 X
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;; give the turtles an initial speed
' Q. Y: z a3 j% | ask turtles [ set-car-speed ]2 e4 Q, r2 B- A
* x3 O: }( u* Y+ R# w) `2 W' f reset-ticks
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6 Y; ?( V& o* H7 k {5 ?) M5 j& x3 G;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet: ~, J% G5 G3 P( y( C
set phase 0+ o# r4 N' w% c5 b
set num-cars-stopped 00 I t/ c/ {& Y( P
set grid-x-inc world-width / grid-size-x( R q; P9 w9 j2 w" [0 l5 U
set grid-y-inc world-height / grid-size-y
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" ~5 ^5 Z8 D* o# J ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary" Q6 L$ x' ?8 H; J1 D
set acceleration 0.099$ s5 K0 c* w% W+ x; E G
end. l. ~3 [( {( g' c$ U
1 { |! c% {) i; c;; Make the patches have appropriate colors, set up the roads and intersections agentsets,2 j, ]$ [, T9 V. m
;; and initialize the traffic lights to one setting5 V4 I8 C, }, C2 k. t
to setup-patches
* U+ O( e& C, U& u) b$ m0 y2 ?6 w ;; initialize the patch-owned variables and color the patches to a base-color
( V4 J0 M% w" n7 H6 U, y9 T ask patches
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set intersection? false+ p1 K! H( b- p
set auto? false
4 B7 \% b2 J5 m: |3 U$ N5 c set green-light-up? true3 l( g+ ^" _) |# f% u# C* b
set my-row -18 D8 c: j" o: Z' R
set my-column -1
, m+ K2 Q+ h4 r. _9 y! f set my-phase -19 l$ X; W+ m8 y! H
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets _+ D5 v2 d+ ^. a! g
set roads patches with
) \( A: q) W7 N- b [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
; r8 F* o' H$ N) S (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
4 p2 b3 g1 i4 q$ a; R! O& I# G y set intersections roads with
2 y7 _) J4 X" `/ r/ S [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
( P2 n. G. v% A* P6 e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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" @# Q/ e C5 i8 H8 |: N ask roads [ set pcolor white ]/ l9 t' j/ ]+ H8 h" ?2 J
setup-intersections0 f6 o- C* l: @
end
l& n2 U! k' E1 u其中定义道路的句子,如下所示,是什么意思啊?
$ e$ [5 P J! F7 m8 u set roads patches with5 d: h$ _, S9 K
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
4 B* \! m- h7 S- G/ G (floor((pycor + max-pycor) mod grid-y-inc) = 0)]) F5 V' k5 l0 G4 V/ F# 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? |
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