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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: s; H! {2 m, c5 Bnetlogo自带的social science--traffic grid这一例子当中,
1 j' r& e q! R/ Z( o% b4 }2 uglobals; Q' Y1 k. j& Q6 C/ y
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grid-x-inc ;; the amount of patches in between two roads in the x direction. v! b o( [1 A5 D* _, M0 `& _
grid-y-inc ;; the amount of patches in between two roads in the y direction6 Y8 i. o7 E) A9 P+ Z
acceleration ;; the constant that controls how much a car speeds up or slows down by if
( R- C; p" B# Y% I t. x) j ;; it is to accelerate or decelerate$ E& V# F, a. @* x9 ?6 N3 m& O) O6 K
phase ;; keeps track of the phase
6 g2 T4 s! F, Z: z" U3 Q num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
4 r) k; y# v5 |, n current-light ;; the currently selected light. F1 F) H$ S. B- ]- t3 Y
1 c' L! v5 j, m& N1 q$ P ;; patch agentsets$ `7 N$ x# r% x! U
intersections ;; agentset containing the patches that are intersections
* e" E* i: c) X$ w: W roads ;; agentset containing the patches that are roads
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turtles-own2 g. ^; J d9 j" P- s
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speed ;; the speed of the turtle
( h7 ?7 A, \! r* p4 C up-car? ;; true if the turtle moves downwards and false if it moves to the right- G& k( D9 }, O
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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1 D& W0 W* [0 l; n! Y7 \5 `$ ^9 h. f intersection? ;; true if the patch is at the intersection of two roads9 K ~6 x, E7 ~) j
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
5 j# _# C' k1 X$ m0 ? ;; false for a non-intersection patches.
9 s# S' ^9 D/ y4 F! j7 |. Z my-row ;; the row of the intersection counting from the upper left corner of the
# [- Q. n3 g$ ]1 l: _8 s8 P* ] ;; world. -1 for non-intersection patches.
# w, g& m, Z; ~& B5 T' b; p2 j my-column ;; the column of the intersection counting from the upper left corner of the+ Q; f, m4 N- {
;; world. -1 for non-intersection patches.9 m1 z, {) T+ o7 W( A5 B; W
my-phase ;; the phase for the intersection. -1 for non-intersection patches.: K& V! S5 H, W6 x0 J
auto? ;; whether or not this intersection will switch automatically.7 d$ A2 d" Z* F* O/ y* p
;; false for non-intersection patches.7 i/ [+ ~$ m3 t
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;;;;;;;;;;;;;;;;;;;;;;( K" ^4 s% [4 j o; [8 L6 h4 x
;; Setup Procedures ;;
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6 t8 h6 k5 v$ J/ ], `;; Initialize the display by giving the global and patch variables initial values.
' X: z: ~+ ~0 s, [;; Create num-cars of turtles if there are enough road patches for one turtle to
( i) Q6 q7 d8 I5 s3 P+ c5 ~. e;; be created per road patch. Set up the plots., V4 p4 e) Y# b
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables
1 O# w& b- |8 g, [0 h3 X3 X setup-patches
- C M% h6 B+ G( W make-current one-of intersections6 |. {* H* E& \0 l; |$ r
label-current
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! a9 Z0 B7 F4 B& i" U set-default-shape turtles "car"
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if (num-cars > count roads)' C# V# q" L4 W8 z
[
5 {2 |, g. ?+ q. \9 g } user-message (word "There are too many cars for the amount of "% t y( v) P1 H# @8 o
"road. Either increase the amount of roads "
4 J$ n7 Y3 M, q+ `; W$ Q& k5 v "by increasing the GRID-SIZE-X or ". x2 T) U, Q1 M ^7 _
"GRID-SIZE-Y sliders, or decrease the "
F; ?/ ~+ y" F1 X "number of cars by lowering the NUMBER slider.\n"
8 _% R3 `% ?3 ]7 c7 S "The setup has stopped.")- y V2 v8 u1 \2 I
stop
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6 Z' U1 i% N4 m8 l4 C ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
& r" `9 o' h8 u5 j. R/ ^ crt num-cars
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setup-cars
4 [: h+ V( ^& v set-car-color
6 u, V8 w1 Y( A e- Y- j record-data/ S. }8 u+ ]' p
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: I0 l: d7 l9 _+ I" j8 a8 N9 |9 u) a ;; give the turtles an initial speed
; I3 J/ x6 S% e$ W ask turtles [ set-car-speed ]$ w4 S% y" a7 ? H5 w
9 H6 M1 { B1 B: b reset-ticks3 q b4 [' a" x
end
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$ J3 c2 x$ Y* y4 H4 ]$ D;; Initialize the global variables to appropriate values
/ c2 a8 F$ q: T' s ?/ M& tto setup-globals
2 B& p3 S8 `* `5 Z* ~; W set current-light nobody ;; just for now, since there are no lights yet
3 ]/ s& T" c. v) m. m3 G( a set phase 0
9 `, b: |/ ?; w5 V set num-cars-stopped 0
- N2 x5 l2 r4 ^ set grid-x-inc world-width / grid-size-x
$ o- h7 ?( r9 O3 \! h. ~$ T set grid-y-inc world-height / grid-size-y
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary: |6 [$ X, R" N/ ^" [" W
set acceleration 0.099
1 R' B3 L% t2 }% Y( C5 Aend
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9 ^# f3 n* y* k+ K9 \;; Make the patches have appropriate colors, set up the roads and intersections agentsets,1 |8 w) J* B; f* D( Q
;; and initialize the traffic lights to one setting! q) H$ V* j+ W" n$ n
to setup-patches
9 O8 X9 e# g7 ?6 m3 I/ b ;; initialize the patch-owned variables and color the patches to a base-color3 c- C3 {* x$ C0 P- {" U, A
ask patches
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. f6 R, ~* M. X) Q5 s set intersection? false$ m7 i! v2 o2 b0 | u( T
set auto? false5 l4 Z- ?' `7 f, Z) C
set green-light-up? true# \6 a* Q& ? C1 E$ \
set my-row -1
7 }# e' F9 G- S; M- x5 P set my-column -1
! w) t- R+ W& @+ Z# z4 } set my-phase -1
- K9 S) b7 v" c0 [ set pcolor brown + 3
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) q! w: z# y2 h! K+ t" D6 |" m! Y ;; initialize the global variables that hold patch agentsets
$ C& Y7 a& a. G6 u' `) @. u) c set roads patches with% T8 Y" I" ^+ c. B7 ?7 T
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or( L1 e: ]. o/ e2 j; X7 V: | s
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
. a A8 N" c2 @+ F/ S0 l+ R set intersections roads with
+ w/ i6 b7 \8 D a [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and1 T- \' h9 c( ?! y& M1 I2 H
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]$ k6 M8 h% z' C+ q" P5 o: A
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ask roads [ set pcolor white ]& ]! r& b6 B% `7 N9 k9 c/ t
setup-intersections
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$ n5 d, Y# m' f; G/ n5 |. l# U5 B其中定义道路的句子,如下所示,是什么意思啊?
: ~; @! Q+ c1 x+ M0 @ set roads patches with0 D( [9 i8 n+ p
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or& V9 o: q0 m1 _$ I
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]6 ~' W$ a5 d2 y0 ?& t0 l
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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