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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: |5 O2 V* Q2 v( e5 ~
netlogo自带的social science--traffic grid这一例子当中,' _+ E6 [9 c/ b) e( j' H! Z$ K
globals; l. P$ m( t; H% M1 C
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' x& A6 G: m8 ^ grid-x-inc ;; the amount of patches in between two roads in the x direction, p! Y Z' X" J: y" @8 g+ ~6 J% W
grid-y-inc ;; the amount of patches in between two roads in the y direction
2 f% P4 b& f, k! ^$ ^ acceleration ;; the constant that controls how much a car speeds up or slows down by if
* }" A4 [. k \! b% O, p6 n ;; it is to accelerate or decelerate
' I- Y/ e) k. c/ x1 f6 f phase ;; keeps track of the phase
u; z* L8 f5 t6 W6 p num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure$ u5 u' l. M- ^! O( P; b `
current-light ;; the currently selected light0 Z0 h! {! e; B7 b
2 E4 e* N: a; c; E( c3 ` ;; patch agentsets
# Q" f& ^- G: P b8 |: W7 X intersections ;; agentset containing the patches that are intersections! V! y+ `2 K! A$ m0 k1 P. ~6 ?( i
roads ;; agentset containing the patches that are roads
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turtles-own7 y5 A3 `$ I1 ^7 C8 a& x4 ?3 j: f
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speed ;; the speed of the turtle
' M3 x3 E; T" O& j! n' K! V9 E up-car? ;; true if the turtle moves downwards and false if it moves to the right) X/ H4 u* v; r* J
wait-time ;; the amount of time since the last time a turtle has moved% e7 u6 ~. L4 N8 \) j d
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patches-own
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+ L9 P3 l8 F8 Y0 x/ t6 F& e intersection? ;; true if the patch is at the intersection of two roads
4 e7 s; @( r4 t2 M `/ F green-light-up? ;; true if the green light is above the intersection. otherwise, false.
% r; O/ O5 a7 h# _) B4 S ;; false for a non-intersection patches.
. I4 M0 n0 _! q5 @# J3 G my-row ;; the row of the intersection counting from the upper left corner of the& p$ d& Y X" H4 S
;; world. -1 for non-intersection patches.& i! [+ g! L8 j" G7 H Q# C
my-column ;; the column of the intersection counting from the upper left corner of the
) V9 L O' g' W ;; world. -1 for non-intersection patches.) D5 F- K) |1 A9 f% S9 l: }
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
j7 o" h7 H& @ auto? ;; whether or not this intersection will switch automatically./ p4 a) z; ]0 ]; K, w
;; false for non-intersection patches.1 A" D) W( k- W+ @2 i
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7 t- I! B* l, A! I5 G;;;;;;;;;;;;;;;;;;;;;;8 T! @# w. ~/ X4 m' `: Y- m* N
;; Setup Procedures ;;0 ^, g5 {) G& B- M' C; s
;;;;;;;;;;;;;;;;;;;;;;
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4 I9 S; B: f/ u) {;; Initialize the display by giving the global and patch variables initial values.
( Z0 T, K6 H' {, w;; Create num-cars of turtles if there are enough road patches for one turtle to
6 q) b6 P+ P$ B, T" L# o;; be created per road patch. Set up the plots.
& c; n% V9 I" zto setup! l0 |' Z8 Q4 Q4 r6 y, e
ca
) ?$ D% _) f/ b# ~ setup-globals! O; y6 `; L( r
( A3 ]2 U m0 }" v; w ;; First we ask the patches to draw themselves and set up a few variables+ S6 n# G) o4 M7 ?6 Y0 U
setup-patches
& O+ {' G) D1 p make-current one-of intersections5 S0 O* |5 [6 e, r& H
label-current
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set-default-shape turtles "car"
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if (num-cars > count roads): E& a* a1 t8 ^& R) `
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user-message (word "There are too many cars for the amount of "
/ L3 m" I6 j& ~9 Y "road. Either increase the amount of roads "( J1 g4 r1 C- ^( l* c9 b% D
"by increasing the GRID-SIZE-X or "! K9 ]. d0 D& G* K( @/ `
"GRID-SIZE-Y sliders, or decrease the "& T. m9 i! |$ B1 s, Y F9 o
"number of cars by lowering the NUMBER slider.\n"- b! o% b% t3 E$ C* H
"The setup has stopped.")
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' ]/ |8 Y; p' n5 m0 ? _, f0 Q, Q ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color/ g4 @: ]6 z* ]; L
crt num-cars
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3 ?7 \/ W- _6 [ M setup-cars
. b. [" h. t7 O3 G* Q set-car-color% i( }: U1 t# o5 R5 _! @
record-data L3 t5 c6 s/ S7 }( u' Y, E
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;; give the turtles an initial speed
. \& I' R- V' d5 E5 I1 t5 m ask turtles [ set-car-speed ]- F+ d' s( Z. c* S5 Q* U
' S/ Z" m$ d7 L1 p) U; b8 ~ reset-ticks
0 L! o# Y/ I" Tend
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;; Initialize the global variables to appropriate values
7 W h/ P" U- Y) H+ b8 b! @4 lto setup-globals
8 a0 R Z# o6 w. k* V/ y% E3 Q. [6 l" U set current-light nobody ;; just for now, since there are no lights yet
9 r8 P2 v3 { Y2 C0 R set phase 0
+ s6 P5 e& K) G; \+ g S2 } set num-cars-stopped 06 [0 [1 \% ]: t& D. F7 V
set grid-x-inc world-width / grid-size-x
1 B# o) ?* f7 f4 m set grid-y-inc world-height / grid-size-y
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- N9 M4 T6 B: O8 L! q, q) ~) o6 R8 { ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: y, ~% l1 j* J
set acceleration 0.099
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,5 B( B. q& a3 |, Y
;; and initialize the traffic lights to one setting0 ?* E! U/ _8 K& ^ V' g. W
to setup-patches
' m$ U, `4 M- r |8 }' l( U* M ;; initialize the patch-owned variables and color the patches to a base-color8 e+ A( ~+ d! U/ w2 h# T
ask patches
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3 u7 {* D7 A- W* Z5 V' \. W# | set intersection? false
" s. W2 g1 {2 T. ? set auto? false
% |/ {8 M9 n _* b set green-light-up? true
4 d& M l3 P4 H) i; v9 O set my-row -19 r9 l, j1 `( r3 s5 ?# m9 O& E
set my-column -1
, `, }4 B( v0 ?: e set my-phase -1
6 Z# E* @; k/ ~( A' a$ P2 c set pcolor brown + 3; k/ K+ j! Q! `5 B+ B' o: d0 _, w
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;; initialize the global variables that hold patch agentsets
. a2 I; |9 h; M" p) p* K1 H" \ set roads patches with
4 k% s8 Z0 R! H1 \9 V! L8 o. B [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
1 k* Z& m+ n r (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
/ ?+ ]; N% B) R! r; k/ c set intersections roads with
: _( R( b( q: ~" y5 `2 u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
7 a) q* S) y3 E0 _" O* n (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
4 X; b9 G1 l; P2 X% c! r$ O d; F setup-intersections
! f! G" S. a; h8 m6 }$ Gend
3 S0 ` }3 W: `6 ~9 u其中定义道路的句子,如下所示,是什么意思啊? c ^, J+ t! f! U) q) U
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]# N5 J5 W6 h5 o) O) R9 E
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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