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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。
! {) u2 X$ B: g9 U7 r6 R( e$ Anetlogo自带的social science--traffic grid这一例子当中,+ J9 V, m6 u6 z& d
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
# x) K+ d5 V. T8 {' H. ^ grid-y-inc ;; the amount of patches in between two roads in the y direction
" @! g1 N& {2 L) e acceleration ;; the constant that controls how much a car speeds up or slows down by if9 w& Q: K0 @/ i, }0 c3 l
;; it is to accelerate or decelerate
& L5 ]5 X- J/ _1 z' F' c phase ;; keeps track of the phase% Y' V* y3 U/ }: ?! H
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
T0 y* K. H. e current-light ;; the currently selected light" r& }& H @8 n: j0 n, Q. d& C# K8 |
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;; patch agentsets
3 j6 }9 I. I$ U: p0 T5 D intersections ;; agentset containing the patches that are intersections/ r$ a# @9 P( u& Z$ K- ~
roads ;; agentset containing the patches that are roads# C8 _% ]# x6 \6 Q" j0 A$ ~- n
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+ ]6 D/ A) J! N0 dturtles-own! e8 [+ x9 H2 W9 g
[
% [6 |0 a! P/ K! ~+ ?6 _ speed ;; the speed of the turtle$ `! }" t. N! U9 S
up-car? ;; true if the turtle moves downwards and false if it moves to the right
: B+ [0 u% M$ {; L5 _/ m6 p2 l wait-time ;; the amount of time since the last time a turtle has moved
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& g9 g( G) o- D) xpatches-own, S6 t) `. U9 ^# r
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( I2 I5 g" O8 \+ k7 F intersection? ;; true if the patch is at the intersection of two roads1 h1 O9 N1 M$ y( [
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
' P" P6 U. J8 U9 K) ~& ^2 U; l ;; false for a non-intersection patches.3 B! d5 X9 H9 s+ \! \+ V4 g
my-row ;; the row of the intersection counting from the upper left corner of the: a; S* Y5 n' Z3 e
;; world. -1 for non-intersection patches.( w# A5 R8 @' _$ ]& a
my-column ;; the column of the intersection counting from the upper left corner of the" O2 n. n& I! C, V$ B
;; world. -1 for non-intersection patches., Q5 S7 u4 s$ [. B
my-phase ;; the phase for the intersection. -1 for non-intersection patches.9 c7 Z# M3 w! P8 d$ y A& T! W6 \
auto? ;; whether or not this intersection will switch automatically.) p* \' S7 [; ~) s: m2 O: g7 v
;; false for non-intersection patches.# k1 V" S( F' F' K
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;;;;;;;;;;;;;;;;;;;;;;0 ?5 |/ o2 p* T6 S+ S7 U+ }5 w
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.3 d M, @6 p9 _
;; Create num-cars of turtles if there are enough road patches for one turtle to7 r% B) h$ B2 e$ c4 e$ \. v
;; be created per road patch. Set up the plots.
0 W6 I8 R) N8 A! p, eto setup: k1 C" z! D0 D8 w% ~
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setup-globals
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! m( X$ n* w# d ;; First we ask the patches to draw themselves and set up a few variables
- W5 X, L( [ f6 O# n setup-patches
M2 L# L8 S/ p- U8 ` make-current one-of intersections5 p; J9 u- l$ H
label-current
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" T3 |5 R( Y4 @ set-default-shape turtles "car"* ]1 N) Y- s# m) }( A0 B% u
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if (num-cars > count roads)6 w4 n n4 t! f) o
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user-message (word "There are too many cars for the amount of "
/ O8 i$ b& l2 A: H4 N" A* p- { "road. Either increase the amount of roads "
4 a: T$ f* |# q1 O( o "by increasing the GRID-SIZE-X or "2 B' g7 K5 V* K- g
"GRID-SIZE-Y sliders, or decrease the "2 a/ {0 k+ Y1 Z) J9 q ~! ~0 p; W* S0 r
"number of cars by lowering the NUMBER slider.\n"
2 @7 o5 r- y7 D1 T( Q "The setup has stopped.")
3 H+ r M Z' m% ^, j stop9 ]; _ w3 E" k
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4 K2 U/ P, r4 V6 S5 U ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
[. s L2 _6 ~) c; Y crt num-cars
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' b. ?* k# n' Z+ Q( I setup-cars( F# }1 q: j" c8 f
set-car-color/ g: R3 R: S2 _3 W% w
record-data
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;; give the turtles an initial speed
3 e& f# ]0 o8 n2 c" U: K ask turtles [ set-car-speed ]5 u2 p# |8 ~ C& S* `
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reset-ticks
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" G' c7 M9 X/ |. s3 U u;; Initialize the global variables to appropriate values
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set current-light nobody ;; just for now, since there are no lights yet' w/ ^( I8 t& e. z# h
set phase 09 Z4 r- Y. c6 ^ ?5 d3 M: ^
set num-cars-stopped 0
0 f2 y0 H3 h" {: T set grid-x-inc world-width / grid-size-x
3 j4 p. N7 r- W& l2 b: L U 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 boundary3 Y, D+ N8 y. o3 `7 N* A/ M3 k
set acceleration 0.099
) x& T; Z' Z5 g- ~; }end. ]5 J w7 ^, |( |" X4 R; T
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,# R3 x% E/ y( @0 k, k" e9 C2 `3 U
;; and initialize the traffic lights to one setting
7 `2 q3 ~: m9 j3 W* kto setup-patches. c1 e- E$ N2 ^- `( Y
;; initialize the patch-owned variables and color the patches to a base-color1 @ x! d( |; _# b
ask patches
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2 a5 S& W( I& h" C+ u set intersection? false5 Q* c: c8 M- {1 f: l& B, J
set auto? false* n# y! N. }5 [: Y! Z: M3 F
set green-light-up? true0 E! k5 _0 V0 W0 b1 X8 h* s! s0 @
set my-row -1& w- Y# a" i7 u8 D( |/ @
set my-column -1
# H. t% S% F" i5 }3 j set my-phase -1) Z1 G% ?0 `8 p# J2 T/ B7 ]0 q
set pcolor brown + 3$ [! a) m7 @! m
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;; initialize the global variables that hold patch agentsets$ U; m2 P7 b( n
set roads patches with
- w3 ?3 u# N9 m8 r* X- X* F, O [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 H2 f( Y. f G/ I! a1 e$ n
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
$ i% J$ k- g7 K1 E) z! N7 n+ J set intersections roads with# x9 H9 G) f* R' X! Z
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
4 Y$ r0 n! @5 }' h' s (floor((pycor + max-pycor) mod grid-y-inc) = 0)]0 R3 W4 d- ~3 Y6 n- K0 v9 X+ N
0 j, R* d% K9 |- r* Q k ask roads [ set pcolor white ]
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% P a2 |) k- D8 _* o4 \. s3 r4 M- `其中定义道路的句子,如下所示,是什么意思啊?$ X( e3 a! Y. Y+ i2 v
set roads patches with6 v0 r# A3 G' F K
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ c9 \ A9 G$ d& e (floor((pycor + max-pycor) mod grid-y-inc) = 0)]' Y' _6 _3 _' A5 x. I
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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