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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。+ G7 e9 w# `% a
netlogo自带的social science--traffic grid这一例子当中,
) d' }) L( i6 n, L2 Q% |globals( u$ J$ K5 C) L: z/ }* r/ _) l
[
5 y z5 G2 P* H( n4 _4 C- ? grid-x-inc ;; the amount of patches in between two roads in the x direction
) n6 j8 F. c9 D, V" w grid-y-inc ;; the amount of patches in between two roads in the y direction% d* F9 G5 E7 _9 M0 t' `# L
acceleration ;; the constant that controls how much a car speeds up or slows down by if$ _3 k0 P4 b5 K3 r) ~1 D' h' S1 t) _7 X
;; it is to accelerate or decelerate
/ q7 u% ]) m$ ?, e phase ;; keeps track of the phase
# Y3 T- c3 R( W2 r num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
8 x0 p- A6 p& p4 [/ b) b9 O current-light ;; the currently selected light
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;; patch agentsets
7 j. ^' I0 x2 e, j7 a: ?6 } intersections ;; agentset containing the patches that are intersections
# L/ x% v. v& G; |6 B. w7 Q3 D3 z roads ;; agentset containing the patches that are roads
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c$ j1 n4 Y/ W" Oturtles-own
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2 k- v2 r: N/ \: P, n speed ;; the speed of the turtle, N3 L6 k$ n Q% x! B
up-car? ;; true if the turtle moves downwards and false if it moves to the right
$ M2 u1 o9 X- [" V+ o6 C3 P7 y wait-time ;; the amount of time since the last time a turtle has moved
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* w5 j! R0 z- b: d2 Jpatches-own( C" h; w, E, Q& h9 e* h* Q( N
[
! B) d; @2 \8 a$ x+ o intersection? ;; true if the patch is at the intersection of two roads0 T$ y: s2 h- ]; g
green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 J; w: r. \" s( L O" b( i
;; false for a non-intersection patches.4 J2 Y; W7 z( E2 l0 Q6 B
my-row ;; the row of the intersection counting from the upper left corner of the- p3 o! P- g9 p6 H+ H9 R
;; world. -1 for non-intersection patches.; r: D3 S6 a/ _, w; F$ s5 f
my-column ;; the column of the intersection counting from the upper left corner of the: o/ Q! J" p9 H6 v) ~% `, a4 { p
;; world. -1 for non-intersection patches.
$ D: `/ U5 c0 r+ B9 h1 S! F' x7 w my-phase ;; the phase for the intersection. -1 for non-intersection patches.
5 B9 _6 Z* u( [7 D: @ auto? ;; whether or not this intersection will switch automatically.$ ^2 c8 [6 w+ n7 T% K! k' ]; u' l
;; false for non-intersection patches." r& x+ F8 B: [3 D8 S+ i0 A) ?
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4 x0 ?$ K& `8 h! `;;;;;;;;;;;;;;;;;;;;;;5 N7 W6 q0 ]0 m) _ d+ D
;; Setup Procedures ;;. P: V" Q/ u8 f% I# p8 d* I7 N$ E
;;;;;;;;;;;;;;;;;;;;;;" Q. W: M/ j9 _: q* F
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;; Initialize the display by giving the global and patch variables initial values.
8 y" N1 Y$ x9 ~4 ^6 I1 k;; Create num-cars of turtles if there are enough road patches for one turtle to; q1 q* r0 n* ]
;; be created per road patch. Set up the plots.
O2 ~2 R3 u) E& i% r( T8 G* Ito setup
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: z3 H+ M% M3 U% M setup-globals
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$ O" e( {& p) Z: I ;; First we ask the patches to draw themselves and set up a few variables
W) S; E* |" R7 S! O0 E setup-patches
! ~1 l$ y7 p7 y/ n, \* J9 H, q make-current one-of intersections3 \: m" m1 t8 P' ]: E
label-current; I+ K' u, R9 N9 ?" b, l, |7 W
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set-default-shape turtles "car"1 L5 q: ?; Z2 g) f( a
# i Q, H6 M, r2 n if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
# w6 ^# y" s- @' P* P6 W- z "road. Either increase the amount of roads "5 S% O6 ?( {7 W7 f4 ^
"by increasing the GRID-SIZE-X or "8 s" X# s( c) ]2 j% e# H
"GRID-SIZE-Y sliders, or decrease the "6 L9 F! Z9 r; x |7 q* Z9 B$ [4 x( u
"number of cars by lowering the NUMBER slider.\n"
( `, j/ c3 w1 ^$ i9 E "The setup has stopped.")4 T3 [0 u& C' ~+ }7 } }
stop
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;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color0 T. a* \% D2 @
crt num-cars
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setup-cars
' |4 P- C. V' P set-car-color0 C! G5 k) f, y- O) a; p
record-data- [$ ^7 e2 |4 _& l t
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;; give the turtles an initial speed0 t, X/ N& E0 U, l$ Y$ P0 E9 i, I
ask turtles [ set-car-speed ]
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reset-ticks9 w M4 v0 W# w+ ~
end
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8 ~$ H3 I* |- M! S9 c;; Initialize the global variables to appropriate values$ x* U6 V& ?' P: K
to setup-globals4 |5 u. L: x) i: |8 O. c9 r
set current-light nobody ;; just for now, since there are no lights yet" Q0 O" f# Z+ l3 ?* I
set phase 0
" S- w8 p+ s+ s* z) q) d set num-cars-stopped 0
1 j* m8 f! \6 K/ }% R- ? set grid-x-inc world-width / grid-size-x
" s& N; [ e6 C5 ]- R8 o7 R set grid-y-inc world-height / grid-size-y* E4 I( B3 j' _1 B8 w" \( v
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
" _. c* p! E. L1 ^: @ set acceleration 0.099
# R8 N5 U3 x9 b* X: jend# s8 M) }1 J# M4 Q( N
0 [# ^3 D9 V. I3 z- f, u;; Make the patches have appropriate colors, set up the roads and intersections agentsets,8 a) O/ ^7 _% n2 W9 R. I, B* Y
;; and initialize the traffic lights to one setting$ Q6 o$ {' q2 L, I& @
to setup-patches) b. C' a& V( f, H4 V! W
;; initialize the patch-owned variables and color the patches to a base-color$ J( Z j7 d2 I$ c0 F; S
ask patches
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set intersection? false* V+ u. Y# ?6 a7 F0 a
set auto? false0 E( O, m# I" c" A/ j. k3 [
set green-light-up? true
# `$ M' O" ]$ l4 Y G; @0 R set my-row -1: X+ Z7 r8 O& z) j( A4 k m; W8 k
set my-column -1
- v @( x) U2 |/ J; `* H set my-phase -1* W* q9 B0 c* n0 y
set pcolor brown + 3
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;; initialize the global variables that hold patch agentsets% v. y# w0 {0 s$ z' Q B. {7 j
set roads patches with
' a/ F9 W( r; ]. T- B4 f6 |$ ? [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
' p6 G K( B9 f9 c: ~; ~ (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
5 s) T4 C s: N set intersections roads with( _% ]- y8 e; ?5 R! a& L4 o x) @) \
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
1 W4 @+ V* E+ x3 A( Z% a5 j4 z (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]* c" S g3 `+ T# d& D) i: _
setup-intersections2 t6 j* m( v4 C8 s% H
end
g; u1 m$ v2 `: Y7 o" P其中定义道路的句子,如下所示,是什么意思啊?
q+ T, _# F4 V1 g( I/ k) x6 S; \ set roads patches with
! l/ ~- I/ y! P, d) k8 s [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ b" A* G& w% h' B
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]: i2 {) o, ?+ N" |+ d/ H5 D
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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