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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。
: S0 ~6 O- v5 o5 A! D4 [% Rnetlogo自带的social science--traffic grid这一例子当中,
. z/ l( [# y6 ~0 cglobals4 y) b# Z4 @2 k1 A
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9 Y" A4 d9 Q: O M. A grid-x-inc ;; the amount of patches in between two roads in the x direction+ D4 r. Q- K8 A `: [0 z4 W
grid-y-inc ;; the amount of patches in between two roads in the y direction; U1 v) J+ d7 A" `$ u# F
acceleration ;; the constant that controls how much a car speeds up or slows down by if9 s+ a* w7 ~6 Q! b1 U# x
;; it is to accelerate or decelerate$ N6 x" h+ a& q2 s/ a, J6 ?
phase ;; keeps track of the phase
$ S" K( z7 Z, G# x num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure2 W( n) R* K$ F8 B' _, f: a
current-light ;; the currently selected light3 _( u' b3 R" g7 d# p
. C! g& U1 g. L0 M5 u ;; patch agentsets
: G# H9 x& p0 H$ `, M& g) s, W intersections ;; agentset containing the patches that are intersections
5 @$ E: H+ N% l roads ;; agentset containing the patches that are roads
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' ]8 I! ^& ^ a. b- K% v+ }turtles-own
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speed ;; the speed of the turtle/ }$ @; t1 w1 f2 H& s, A1 ~* l
up-car? ;; true if the turtle moves downwards and false if it moves to the right
& r5 |9 z8 m% g3 H% @' z0 P wait-time ;; the amount of time since the last time a turtle has moved
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patches-own5 q ^1 b0 C, S1 y: @% i
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9 _1 d7 r) R" O& ^1 ^- U0 N5 \ K intersection? ;; true if the patch is at the intersection of two roads- U' z6 ?% O9 t+ F+ D; a
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
- Q: _9 W7 j1 C% K, T ;; false for a non-intersection patches.5 l+ L& w- u# d: K$ L" C
my-row ;; the row of the intersection counting from the upper left corner of the9 F5 \& O" \3 E
;; world. -1 for non-intersection patches.% b; ^5 _2 Z* k* D/ \" l; z4 {
my-column ;; the column of the intersection counting from the upper left corner of the
* B- M6 {/ ~$ Q) h1 T- R# ?5 G ;; world. -1 for non-intersection patches.8 F) k9 G+ w* b) J
my-phase ;; the phase for the intersection. -1 for non-intersection patches. X a) M, z- X5 Z' J- V( F8 M
auto? ;; whether or not this intersection will switch automatically.# A& [. k9 J6 W5 Y
;; false for non-intersection patches.1 }! L4 ]$ U- l3 K/ n
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7 o: g9 h- l+ k;;;;;;;;;;;;;;;;;;;;;;
0 ~3 W* b1 a" q- b;; Setup Procedures ;;6 ?: H$ L& X$ d1 n ]5 `, p& `
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;; Initialize the display by giving the global and patch variables initial values.! d# |/ S1 h/ R8 I$ _3 r
;; Create num-cars of turtles if there are enough road patches for one turtle to
3 I0 u; _9 I+ x: b6 J* v( C- D7 t) D;; be created per road patch. Set up the plots.
$ r3 y6 q4 c2 e. r- U% Zto setup2 d! ^+ `+ U6 o; _, P4 t, ?/ B
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setup-globals! G* R" X4 J0 u. V( S6 P
% W" y: N( G5 y& D. r ;; First we ask the patches to draw themselves and set up a few variables# c9 V$ u/ i+ c7 Z' d
setup-patches
0 n$ v, ~* K: r* O Y3 ]7 K make-current one-of intersections% t, ]+ v* Z* ~& h
label-current; @& P. \) O1 d/ C! J% P7 X- S O1 K
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set-default-shape turtles "car": g" b3 f5 b; }0 S# d5 t
' r! h/ g9 ~% o$ c if (num-cars > count roads)9 c& }" ?3 A, Z" _
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+ y1 x$ C) J& V- [: t3 K user-message (word "There are too many cars for the amount of "! L1 D( k" O4 @1 E W
"road. Either increase the amount of roads "
/ q; H L/ l$ e- t& J "by increasing the GRID-SIZE-X or "( V* u- ~1 E% t% v& V1 }; o$ y
"GRID-SIZE-Y sliders, or decrease the "" }0 U. `% S2 T8 g& ?
"number of cars by lowering the NUMBER slider.\n"
4 Q9 k9 F; Q" E: Z6 Z. \ "The setup has stopped.")2 q8 w+ R7 ~( `1 d M
stop2 d* @* B0 i6 j2 `* D
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3 w# A. N& ^; f ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color/ g0 Z/ [+ T% C$ H' }' \6 p
crt num-cars) h4 t7 ]. X: {8 E3 F3 L
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# ^5 } J& J5 N: X* I' | setup-cars8 A8 R0 Y6 R Q- K; z
set-car-color
/ J: g% v' U( n( q1 W record-data
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;; give the turtles an initial speed
$ R2 A0 G5 a+ N& b& L ask turtles [ set-car-speed ]" r) f( {8 k. c5 o
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reset-ticks8 N: {7 ]2 _, ^: U0 I
end
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;; Initialize the global variables to appropriate values
9 K3 Y( ? T5 k, c- E6 a% Fto setup-globals
2 r4 j" f$ b9 s set current-light nobody ;; just for now, since there are no lights yet
* D" U, V( g, ~ set phase 0$ D! j& r& j9 N$ m
set num-cars-stopped 0
: i1 i- v8 c/ j set grid-x-inc world-width / grid-size-x7 `" Z1 i) Z: o% R, c5 d( j
set grid-y-inc world-height / grid-size-y. c' i6 j& w2 s4 S$ H) Y0 g5 q5 Y
6 [' h8 j. y& N: D2 T ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
( n8 w* z, o% s" { set acceleration 0.099
% V0 o5 }7 s5 R! W1 T2 u$ qend
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, R2 d+ v% f+ z! l1 h. w, m;; Make the patches have appropriate colors, set up the roads and intersections agentsets,5 r( _% F3 j* C$ O7 F% M: n1 J* N
;; and initialize the traffic lights to one setting
3 A: u* j& | i4 y2 \: N) O$ oto setup-patches
4 s ^! M8 m( o, o) R, [8 s1 k ;; initialize the patch-owned variables and color the patches to a base-color" M* N- a& ?6 _ o1 G! p) P7 i; l
ask patches
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) K c/ J- w( b0 U set intersection? false4 z# |" G" D$ C
set auto? false
, h3 F/ d% a# y set green-light-up? true& p5 x& ?( B5 z" Z
set my-row -1
4 l) Z8 ?8 C: A, ]$ _+ ] set my-column -1( a C7 k- {, d! B2 s- [ F, C/ w1 P
set my-phase -1
+ M' u0 }% A5 {, ^' Q set pcolor brown + 3% _" U, V! O4 r8 n) D7 Y
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! z; b4 c% v* ?$ E+ ] a ;; initialize the global variables that hold patch agentsets* W0 ?& b. L5 \: p6 `
set roads patches with
+ t$ Z; q% s* c1 a* C% l [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or+ Z% W1 V, l/ w
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]( x! d& z) L5 O; m+ J
set intersections roads with! N/ A; o! Z% f1 d
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
# S, u; Y' B; Y* s7 } (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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( h0 B5 ?- O) Y+ E; t ask roads [ set pcolor white ]% z' W. I6 S, p% O" s) E
setup-intersections2 j/ J+ L* R/ }1 i' H4 g
end
) G* s4 \5 _- E* {其中定义道路的句子,如下所示,是什么意思啊?
9 m0 l" O" t2 O set roads patches with/ A [: Q) A* {+ G0 K5 E
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or7 v' V7 R0 o! ]- O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% y" l0 q* a$ 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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