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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。
0 I+ O9 ?0 S0 Znetlogo自带的social science--traffic grid这一例子当中,' `* J! R, G" `9 f& s4 H+ z) g
globals
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grid-x-inc ;; the amount of patches in between two roads in the x direction
- V* p4 s% Z( A! r V1 g grid-y-inc ;; the amount of patches in between two roads in the y direction$ L' _' L* @' h$ Y
acceleration ;; the constant that controls how much a car speeds up or slows down by if( j. u+ r% p, c6 p; Z
;; it is to accelerate or decelerate$ I( y+ O9 E1 k
phase ;; keeps track of the phase8 @" X O" U) `2 H% o6 B5 n
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure3 z: U5 u! d- o# V8 p
current-light ;; the currently selected light, M+ U" \3 M t, A, m- ~
) O+ r* r5 q( ~' P ;; patch agentsets
1 W2 W& A, S$ [6 u X" e! _) k% } intersections ;; agentset containing the patches that are intersections
8 `4 p# y1 }/ Y% [' t" c6 {# m roads ;; agentset containing the patches that are roads S6 ~8 o. A8 f/ i
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turtles-own
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9 q- [; j8 E, F1 z3 E+ J speed ;; the speed of the turtle# L- Z9 O6 F' V; {, L7 A! c
up-car? ;; true if the turtle moves downwards and false if it moves to the right
+ p$ p; b. l% @) f, |$ K& v wait-time ;; the amount of time since the last time a turtle has moved# m1 y7 j/ D: w& `9 K5 H: ?* T
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$ L5 f6 ^- g7 h4 M5 G3 ?$ Epatches-own
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intersection? ;; true if the patch is at the intersection of two roads7 h; u! v5 N+ }
green-light-up? ;; true if the green light is above the intersection. otherwise, false.
. E- k; |% ]. Q. z0 i1 R ;; false for a non-intersection patches.* l" |. ]- w1 s1 f- [- ~
my-row ;; the row of the intersection counting from the upper left corner of the
! Z) i# _( `6 q% \- f7 h ;; world. -1 for non-intersection patches.
0 c3 l3 B( e4 I! \ t* a& g my-column ;; the column of the intersection counting from the upper left corner of the
! U- k! Q% s' n; |5 K) @ ;; world. -1 for non-intersection patches.+ I" K5 b/ A$ K/ X$ n% I
my-phase ;; the phase for the intersection. -1 for non-intersection patches.4 h2 t5 y& o& P) _
auto? ;; whether or not this intersection will switch automatically.3 Y" }% O7 V: |7 r+ \. l
;; false for non-intersection patches./ p! r: u1 J0 B6 e! O
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;;;;;;;;;;;;;;;;;;;;;;8 T% M# L/ f w/ C8 ~, i
;; Setup Procedures ;;
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;; Initialize the display by giving the global and patch variables initial values.( D4 C, m- j. j3 B8 _8 S, o
;; Create num-cars of turtles if there are enough road patches for one turtle to/ p. E. N. \( _9 X _% j$ N
;; be created per road patch. Set up the plots.
% F$ c- S2 l3 A8 }; P7 y& zto setup; M- ]+ `" D5 l5 ~( A
ca
8 i. U4 t" ^% v3 a! T, c setup-globals
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6 `1 D' \3 y, m0 k ;; First we ask the patches to draw themselves and set up a few variables) F/ U4 H4 u8 `1 C- p
setup-patches
+ G: u+ t& O4 K9 U0 Z make-current one-of intersections0 {) O/ Y8 j2 s3 S; {- X: D/ g
label-current
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set-default-shape turtles "car"
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if (num-cars > count roads)
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user-message (word "There are too many cars for the amount of "
6 @4 H5 L2 q" b+ j9 L7 \" g4 r "road. Either increase the amount of roads "
3 H/ s" v* n ?$ r& }5 ? "by increasing the GRID-SIZE-X or "
0 G9 R; W8 _7 F' [7 W "GRID-SIZE-Y sliders, or decrease the "; i8 W# d( H+ j5 x; V) ?
"number of cars by lowering the NUMBER slider.\n"
9 o7 ~2 w! G5 j- n2 I( W "The setup has stopped.")
' M8 M' Q% R3 a0 }+ l% \ stop5 O- Q7 G* g E& J# D
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) Y N. c. I) n0 ^ ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
/ \' J9 ~* B {# p$ j. |, h& T crt num-cars
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setup-cars
1 J+ {. d( R) c: O. F: C) n set-car-color o( b% m& d" J
record-data
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0 T% u9 s, z$ H+ U6 P( Y ;; give the turtles an initial speed
) W( \, i' t. ~- z0 l# E ask turtles [ set-car-speed ]9 T# F4 |$ Y2 ^
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reset-ticks! w* H- X7 M7 w ]
end- X& _0 B; m5 H, z/ n1 Y: o
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;; Initialize the global variables to appropriate values% }) A- Q9 h8 j: ]% M+ d) r0 Y3 J
to setup-globals! F# w9 s% j$ [7 Q4 ]
set current-light nobody ;; just for now, since there are no lights yet* j/ _% c" e5 h# R8 E
set phase 0
* H0 H2 `$ f+ F& B+ z2 Z set num-cars-stopped 0
7 S2 l$ F" j. M: R set grid-x-inc world-width / grid-size-x4 H9 z) }5 @( O [& a* H6 Z( b( Z
set grid-y-inc world-height / grid-size-y" P- `% o# G+ [
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;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary2 z! U4 o% i5 [+ \
set acceleration 0.099" J; x$ @" b3 A1 r
end
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,: D: P; K; @# }' e. v2 X
;; and initialize the traffic lights to one setting( F4 ^# N2 p3 H% X
to setup-patches
0 ]3 |: F( C2 T2 R ;; initialize the patch-owned variables and color the patches to a base-color
* a. _7 C/ p3 }% S0 Y% ? ask patches4 V" R0 b9 w( p* }- R: ]1 w- o
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set intersection? false1 {1 e. d$ S( h& N4 N J) S
set auto? false; a0 f9 v+ I' a# C5 q4 [7 D4 E
set green-light-up? true4 d& V- [1 Q! L
set my-row -1
) T- u# w5 R6 g+ b4 p set my-column -1
. `. g5 W1 n/ f, ~ set my-phase -1' u3 u& G( M2 d( V; E
set pcolor brown + 3
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0 U0 M0 m: Q, ? ;; initialize the global variables that hold patch agentsets
+ z! g: U: j$ d set roads patches with
- b" H# N$ W" h% O' V' | [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or
$ J, I9 A/ P7 @! v, s (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
; m1 B- [6 @9 X5 F set intersections roads with
7 ^3 m1 {; d# T2 i3 i2 O3 R1 t% z [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
" d( R8 Z; L6 I3 f (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]# z" R( S, n4 i2 X8 G
setup-intersections9 Y$ k, M: T) H( s* a- p7 d
end3 `5 b) ~4 ]" O' W: q2 c- _
其中定义道路的句子,如下所示,是什么意思啊?
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[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or) L0 W- n- U! X, |0 U: j# E
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
3 q. Y4 @! Q8 ~3 t3 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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