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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。
) \- K6 z, q9 @netlogo自带的social science--traffic grid这一例子当中,! x- h/ `' w2 y
globals
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1 k( S5 | X9 u* G grid-x-inc ;; the amount of patches in between two roads in the x direction+ G7 W5 v- Y/ ~# b3 v
grid-y-inc ;; the amount of patches in between two roads in the y direction
9 L6 x% j4 v/ ]" x7 x% x acceleration ;; the constant that controls how much a car speeds up or slows down by if
_& a8 M$ H( I; b/ \, p- W ;; it is to accelerate or decelerate
: h9 a2 p0 J. n- z3 Z% s8 k phase ;; keeps track of the phase
4 [( l& M" C1 c7 F& S" L num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure1 U. c* b% V \( n+ ?& L4 q# j4 \% }
current-light ;; the currently selected light# e* k& }1 f9 N9 u& {8 Q+ n* x
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;; patch agentsets
9 M. O) p" G+ r, D+ o8 l& b ^ intersections ;; agentset containing the patches that are intersections8 o7 Q) s( S* R1 l6 a0 F5 C: E
roads ;; agentset containing the patches that are roads
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turtles-own
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- X' T' F# }' i d$ @) c speed ;; the speed of the turtle% g2 w2 w0 [, F- E, k
up-car? ;; true if the turtle moves downwards and false if it moves to the right9 j% K0 E) C7 u7 u
wait-time ;; the amount of time since the last time a turtle has moved" ~3 M, \6 i5 V2 `# J9 I# p
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patches-own& Y+ R9 k* g; K6 R
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intersection? ;; true if the patch is at the intersection of two roads
% W' u) C% k- z green-light-up? ;; true if the green light is above the intersection. otherwise, false.
7 {* O2 B! X5 j3 l0 n- y4 n ;; false for a non-intersection patches.: S- x# x# b; Q
my-row ;; the row of the intersection counting from the upper left corner of the; C. t7 O' c0 a/ h7 A
;; world. -1 for non-intersection patches.6 z3 h3 w# E. l1 x
my-column ;; the column of the intersection counting from the upper left corner of the+ p/ k6 Y$ a- r: V$ a# B; X
;; world. -1 for non-intersection patches., Q: @5 b9 V8 N) m C
my-phase ;; the phase for the intersection. -1 for non-intersection patches.. Z% Z" v- {( }/ Z
auto? ;; whether or not this intersection will switch automatically.. h$ g0 e" N& u7 U9 G
;; false for non-intersection patches.
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;;;;;;;;;;;;;;;;;;;;;;- [. f. c% R b0 b. C- @
;; Setup Procedures ;;
9 T2 Y& j% j1 d: V- Z% A;;;;;;;;;;;;;;;;;;;;;;8 @4 h) W. ^& E( W
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;; Initialize the display by giving the global and patch variables initial values.
0 o1 \( @" G8 N: b/ I6 ]: O;; Create num-cars of turtles if there are enough road patches for one turtle to
- {# o: D H) y$ \! ^: @1 `;; be created per road patch. Set up the plots.& S0 [" L% D3 o% y" F9 o
to setup
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setup-globals
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;; First we ask the patches to draw themselves and set up a few variables3 H; Y% B; k3 F1 y1 |
setup-patches
1 L i. N/ K R0 _( U7 K5 i make-current one-of intersections
* J. x0 X; m4 m+ g label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)! J! i/ L: a$ _# ~ l/ l" a
[
3 ~* |6 \ f; E, }5 y% ^, j user-message (word "There are too many cars for the amount of "
7 m* ?# s" ? m' s3 l' d7 }! r a8 u "road. Either increase the amount of roads ": n* q7 |9 Z* C T/ r4 p4 ~" b
"by increasing the GRID-SIZE-X or "9 x& J3 I0 l. V" \) Q. {/ j
"GRID-SIZE-Y sliders, or decrease the "/ F! ]* G9 L1 M
"number of cars by lowering the NUMBER slider.\n"
3 z; ^0 ]' g) m! L6 { "The setup has stopped.")0 C4 W* G E5 i1 m, M e
stop) `5 v% z% e) f, F
]
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; N. K+ U" b% J1 _, ? ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
" u: |( ~) ~: s% `% m7 M1 R crt num-cars
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setup-cars! c# A- B+ B4 c- _ }6 s: U1 L
set-car-color
6 v: \ A8 E" o z7 |+ r' N4 ~9 o) N5 P record-data
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) ~. R3 o4 e$ a% {# Z( U ;; give the turtles an initial speed
9 e" J1 N; s( d+ _ ask turtles [ set-car-speed ]; `9 ~ I& t- r
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reset-ticks
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;; Initialize the global variables to appropriate values, S. X& H5 F5 q, S# G) k) M
to setup-globals, o4 }" }; r' F% Q2 b
set current-light nobody ;; just for now, since there are no lights yet* _2 f3 ]* O( R. e) P# {6 }% {
set phase 0
% Z0 @! n. ?8 s4 y o7 v" r set num-cars-stopped 0
T. _8 _* F6 H. C5 z5 j3 Z set grid-x-inc world-width / grid-size-x
7 L1 ]7 z' n. L* b X) A9 t set grid-y-inc world-height / grid-size-y5 N2 r3 X5 f7 A! i; L: m1 l" ]& b
+ g' m, M; ?. q9 u ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary, S% T$ I; `7 q9 f1 ~: a
set acceleration 0.099. t" U2 B+ a7 Y- q' z. L8 |
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 N4 T6 @' w# U7 t ^4 B;; and initialize the traffic lights to one setting
# R S, J# j- pto setup-patches
" C' s* s2 u) L5 B' Z. [0 g ;; initialize the patch-owned variables and color the patches to a base-color% s8 g% e- C/ |4 I6 A
ask patches4 f+ v: j; a4 {$ F9 g
[
& a- E- P: }0 H% O8 G set intersection? false$ Z3 d: t% F3 f: G6 j; {
set auto? false
# c- r9 F/ g6 E' t8 C" F set green-light-up? true
4 Q' D# z5 A3 g* ] set my-row -1
" X0 {1 Q+ R, k1 K; |5 j: _ set my-column -1
1 C, Q# J$ t$ y. s+ ^4 |6 D* A7 q set my-phase -1
. g5 ^4 c' K6 {8 m9 t y set pcolor brown + 3; F, L% \4 i# W9 g% |) y
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;; initialize the global variables that hold patch agentsets" ^" x$ v6 ^* B$ d8 Y! _' L$ d
set roads patches with
4 g# u( d6 m3 U1 h6 S4 R0 D [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or+ o: }3 s& e/ {3 D4 S
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]4 \: D! n2 V& ?* a1 @
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]5 i% H, j) E6 }
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ask roads [ set pcolor white ]% U; F" k6 G: j) ~) J5 E, }
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?
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3 }2 p9 c+ U2 |& x) {# g [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
* }8 A( O7 F6 L6 t! \8 F2 b1 A (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 ?/ y# J3 \) k
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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