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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。$ \6 x) l- M0 k& U1 k5 R
netlogo自带的social science--traffic grid这一例子当中,
8 Q k: @, D F+ A' t" oglobals
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grid-x-inc ;; the amount of patches in between two roads in the x direction+ O: g5 R, L: F# J; e- @
grid-y-inc ;; the amount of patches in between two roads in the y direction+ T/ r9 l7 E+ v" b7 W. c1 t" _# Z
acceleration ;; the constant that controls how much a car speeds up or slows down by if7 Q9 n! z* b$ ^& e' l. m: P0 l
;; it is to accelerate or decelerate3 C- O1 B$ n9 _ H
phase ;; keeps track of the phase
$ Y2 Y: j+ z# s# W+ ]/ E num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure8 i* U5 k& \# N0 g0 P. y
current-light ;; the currently selected light
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3 `% P; D6 s E2 u2 G, _ ;; patch agentsets
* ?5 R0 W+ o9 l# J intersections ;; agentset containing the patches that are intersections
f0 \' w* C1 x1 X) E3 B) k9 R; @ roads ;; agentset containing the patches that are roads' h" h- I9 D) x1 o; S3 l7 X
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turtles-own
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speed ;; the speed of the turtle
* N4 `% }" e" Y) }! q; r& G up-car? ;; true if the turtle moves downwards and false if it moves to the right! N, c7 E" E# v" x
wait-time ;; the amount of time since the last time a turtle has moved* _& B& ]* O- ?" h8 {2 S
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: } Q& o/ w; f8 b; |, P/ bpatches-own
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intersection? ;; true if the patch is at the intersection of two roads3 S: S0 r4 w) V0 c* @! w" e& M/ c
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
! F# v9 m4 S% n4 l+ @ ;; false for a non-intersection patches.
2 J1 t- O! _6 d! q- C my-row ;; the row of the intersection counting from the upper left corner of the |( W/ H, T6 @& T. u
;; world. -1 for non-intersection patches.
" G$ i$ H# Q4 ~5 e& L my-column ;; the column of the intersection counting from the upper left corner of the Q1 u3 R, U, i8 S
;; world. -1 for non-intersection patches., j* J7 F0 H4 v; C7 a
my-phase ;; the phase for the intersection. -1 for non-intersection patches.% f. m) [/ @6 b3 e2 y( H
auto? ;; whether or not this intersection will switch automatically.
6 K9 Q; ]/ F/ E# {: _4 _ ;; false for non-intersection patches.2 i0 q' U7 l. c8 X
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i9 k- j1 u( m/ B1 K# H;;;;;;;;;;;;;;;;;;;;;;' K+ t7 X9 ]' O* A- u3 l6 w
;; Setup Procedures ;;1 `# ~5 @; b% \
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;; Initialize the display by giving the global and patch variables initial values.
; r; h: @* L; A" }- t H0 m;; Create num-cars of turtles if there are enough road patches for one turtle to% P7 W0 a) P. U1 C
;; be created per road patch. Set up the plots.
5 T8 I4 P8 d2 \4 J1 Z; nto setup1 x7 f. B- x# _* O
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setup-globals) V* h- h2 `4 h! { L+ b
% z3 E, |0 K8 d. Q ;; First we ask the patches to draw themselves and set up a few variables
# ]- q2 v* v) U2 F ` setup-patches* i5 ]) G% l4 t: b" A
make-current one-of intersections
- B- I- a3 l3 X* b: } label-current6 e9 I7 m1 l6 f/ f. O. u
' M* t6 D2 k! H4 | set-default-shape turtles "car"
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( t$ b* J& |) S9 O if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of ": F4 d0 {1 ]0 R9 q
"road. Either increase the amount of roads "
. c. f1 |; X f8 P/ T "by increasing the GRID-SIZE-X or "+ ^4 l. A9 h+ \+ O1 w! p( o) L; E
"GRID-SIZE-Y sliders, or decrease the "
G6 q( e( b6 R( b, ]. R" m: T: h "number of cars by lowering the NUMBER slider.\n"
+ Y7 \) p$ ]( _- x7 ` "The setup has stopped.")0 x$ p& F; q! m) }
stop* t. m9 B! ~& {' B8 @
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: x4 K: D, ?/ g0 b' K5 @. g. ^ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
* V! m7 e/ y; d+ s0 T' M crt num-cars, Z9 _9 }, W E$ {1 ~
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2 R) s4 Q; d9 u0 X" U setup-cars
& O% y, n% Y" i8 `7 }5 i6 s set-car-color
$ e0 `# M3 p* p _9 M( s4 e record-data6 C# p6 N& m0 H3 {. o1 a
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1 y: I2 Q+ T5 Q+ i( K4 g ;; give the turtles an initial speed6 l4 ^+ ?! H; n( n0 Q. t a
ask turtles [ set-car-speed ]$ L8 C+ Y& ]9 }9 `# S* y
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reset-ticks
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# p- Z1 f1 I" F9 @# d3 h" Y;; Initialize the global variables to appropriate values& @' z/ u6 l1 m; W8 q, {6 W; D
to setup-globals* t' L: b7 ]( |4 K
set current-light nobody ;; just for now, since there are no lights yet
2 s8 P4 x6 J M% A2 @8 G; l S set phase 00 D1 G4 F6 I8 d5 a; D
set num-cars-stopped 0
# M, n/ f# H' g. C7 L* ?) { set grid-x-inc world-width / grid-size-x
6 J- V$ u) \* S$ Q% r1 S set grid-y-inc world-height / grid-size-y
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& K; K) I! U( }$ D' g1 V/ q ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary* ^# l( h; j( D* O) S o: v) n* w
set acceleration 0.099
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: c) @0 d3 p% e9 O! T8 };; Make the patches have appropriate colors, set up the roads and intersections agentsets,
: B, x9 m, D6 k5 A. M;; and initialize the traffic lights to one setting, f |- I1 C( C8 h1 A
to setup-patches
$ f( t- \( d6 n! N- o& p ;; initialize the patch-owned variables and color the patches to a base-color0 Y0 @) `; i- F
ask patches$ Z' L O' N; R u
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2 ?% N8 {3 D4 E5 V0 h4 B o P set intersection? false
7 u) N( l0 C9 g: U( M: O set auto? false1 h! T" _- B# O0 W8 E% `
set green-light-up? true9 Q5 v4 B" F9 K1 B& Z: E
set my-row -1
9 l7 h8 d2 e. }; v set my-column -12 i( l; n0 u5 t0 T; N6 [
set my-phase -1$ \/ ]6 b! G' c5 E
set pcolor brown + 3
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# _0 O3 ?7 J# t6 u+ | u1 [ N1 l ;; initialize the global variables that hold patch agentsets- f* S' n* u$ ~- c& C7 \
set roads patches with
5 p! H; z3 Z. I [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or [/ d( K% k5 Q7 a- V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
% b5 G# t' w' s. R set intersections roads with" r2 Y! o0 s$ a" B8 c
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and& x2 U- Y$ D& z/ L0 T; _
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]2 q9 Z" Q2 ~* R k! e1 F3 P
+ ?$ J+ `4 S( c, C6 K) U ask roads [ set pcolor white ]; |1 _7 B7 t1 d1 j& s4 E
setup-intersections& `4 k2 @* R2 d; @- @
end
* @+ b5 ^1 L5 ^5 I) t其中定义道路的句子,如下所示,是什么意思啊?
+ F, I; n( I/ Q" W; @+ W set roads patches with$ s% J! M; ~- D, ^ }
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
) Q q7 P" S0 m (floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ k8 w. M7 q- P( V( E5 ?8 V1 }0 M; W/ B
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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