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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。
: f, |9 ^% [( C3 A: ~6 Znetlogo自带的social science--traffic grid这一例子当中,( i+ V2 \% t% U2 s& X9 a
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
; ^ j& L7 Y% V2 ~0 `$ N4 h grid-y-inc ;; the amount of patches in between two roads in the y direction
- |7 S% b9 c5 T acceleration ;; the constant that controls how much a car speeds up or slows down by if0 a+ J6 g- g/ I$ Q0 i( c
;; it is to accelerate or decelerate
: K/ z3 x/ r4 Q8 |- ^. a: P5 m- e phase ;; keeps track of the phase
) A0 W6 D, t3 \" ^( |, X5 q) [+ ~- o num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
! ?. ?$ L" Q+ F2 k5 F current-light ;; the currently selected light
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;; patch agentsets& V; {- O" [; |6 r7 t* q
intersections ;; agentset containing the patches that are intersections
# H" z b: @& W' ?9 ]2 w roads ;; agentset containing the patches that are roads: r `4 L- i! R( v* `4 e1 ]
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- x4 |$ @6 _ R bturtles-own
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speed ;; the speed of the turtle
# X. o" F9 l+ u1 F, S, x4 P up-car? ;; true if the turtle moves downwards and false if it moves to the right
8 F3 k1 }! H3 R& d/ Q) X wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads5 W3 z: o- A( P3 f# S
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
/ ~+ F! r7 |; x; g ;; false for a non-intersection patches.
5 u) @* L8 k" N0 e3 @. A6 E! f my-row ;; the row of the intersection counting from the upper left corner of the
0 O% |2 U- J/ V0 x3 V ;; world. -1 for non-intersection patches. X9 X. g. Z1 i8 T* V% Q
my-column ;; the column of the intersection counting from the upper left corner of the
& w6 T) k- Q4 |$ W- D5 W8 V- L ;; world. -1 for non-intersection patches.! S ^2 j- I5 O* h0 V
my-phase ;; the phase for the intersection. -1 for non-intersection patches.! ^( q2 h9 j; Z: r; `1 ?$ ]' M
auto? ;; whether or not this intersection will switch automatically.
, C. ]: q) u4 ^' g ;; false for non-intersection patches.
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* p# b; X5 S' W;;;;;;;;;;;;;;;;;;;;;;
; N' w4 \6 w. `;; Setup Procedures ;;/ O3 V2 B! r* P
;;;;;;;;;;;;;;;;;;;;;;
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- W2 p+ M- C6 ]9 u;; Initialize the display by giving the global and patch variables initial values.( ^. e& y' g: P4 T
;; Create num-cars of turtles if there are enough road patches for one turtle to$ P# H* a* I" c6 T
;; be created per road patch. Set up the plots.
2 s7 Q* h2 B# f8 d6 i# h+ oto setup. B" | M3 G4 i
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setup-globals
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8 R9 G x9 o' x0 S ;; First we ask the patches to draw themselves and set up a few variables' B/ J$ C9 R) M, K% W7 Q) x( E! p
setup-patches: ]0 Q: O3 u. k2 _ i n
make-current one-of intersections
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set-default-shape turtles "car"
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4 u/ `' r* l; Z% S2 \* U if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "' u/ _' c* l6 X2 \
"road. Either increase the amount of roads "& j; Q" o3 d! {# x# H. v
"by increasing the GRID-SIZE-X or "0 w) D- u) l4 ^' q; R
"GRID-SIZE-Y sliders, or decrease the "
) Y# {7 f0 Z( z" H "number of cars by lowering the NUMBER slider.\n"
$ o3 }4 `: c$ |# ], K2 l0 |- G2 | "The setup has stopped.")
& a, f: t. M% c stop
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2 m( \9 L' l0 A* m: O ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
' R3 m2 t) {2 r# S5 A! Q6 J crt num-cars
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~( f* i- [: y" f setup-cars
8 W; z/ y3 E V set-car-color
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& [1 i+ J! u! ]! j2 d ;; give the turtles an initial speed R# ?/ A3 p; V, L) `3 v
ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values
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$ y) ?( z. k: ^$ ^7 m set current-light nobody ;; just for now, since there are no lights yet2 M( o! a( {( Y0 l
set phase 04 o- S3 b- Z/ J/ V2 f' i$ d
set num-cars-stopped 03 H. \0 G# H8 z0 Y$ k2 Z N* B- ?
set grid-x-inc world-width / grid-size-x
4 i- |$ a6 ^$ X set grid-y-inc world-height / grid-size-y& P4 T/ T. n4 \. X5 k3 {/ x5 w
?* m& c2 M' \% ?4 X9 _0 B ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary
5 h& U; R5 }3 ^. t3 y set acceleration 0.099
) X! f' N7 ]$ R4 j/ h/ r) o# ~end
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# }6 s; j7 l9 g } B s2 f% V;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
5 ~1 x/ P% S) x1 ]4 q3 H;; and initialize the traffic lights to one setting+ Z' p! }: g0 q* |. Y3 s
to setup-patches
% C) {' _7 f" ` ;; initialize the patch-owned variables and color the patches to a base-color& R3 G+ m/ ?% {0 c- l* h
ask patches
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/ v" `9 [( R6 i set intersection? false3 {/ C9 Q7 ~9 x1 ?. J; J7 F( y* `# W
set auto? false1 K- A9 |7 b/ f
set green-light-up? true
" K4 x$ L' V+ W4 ? set my-row -1; P# o# L6 d' y) }6 F7 G& s j* d9 ~
set my-column -1/ w8 @, P# P; ~$ V; G
set my-phase -1
1 Y: K# o/ E( K8 ]& V set pcolor brown + 3& p2 [8 U: m* x4 e% z8 x s, A
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;; initialize the global variables that hold patch agentsets, M1 D+ a. D# Y! k2 L- x7 _
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]8 v( t9 S$ J' P- b& l
set intersections roads with$ A. J2 b3 i: i( |+ V* O2 o* t
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and7 h4 N, z. o( h* e: U1 z9 _' L
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]+ e5 X `' K/ h* H1 m1 n
setup-intersections
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其中定义道路的句子,如下所示,是什么意思啊?
# z" B& y7 d% ^ set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
+ V Q+ R6 f" S0 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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