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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。: e+ H6 K7 \1 d! a
netlogo自带的social science--traffic grid这一例子当中," j8 V) Y% g5 C0 M
globals
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* y0 ^1 \" V9 ` grid-x-inc ;; the amount of patches in between two roads in the x direction
6 J$ m7 N, I$ o* _4 k4 W# s$ p: _ grid-y-inc ;; the amount of patches in between two roads in the y direction6 b" M5 c* J4 ]/ ~9 C3 [ \- V
acceleration ;; the constant that controls how much a car speeds up or slows down by if* _8 O1 E# M7 l( Q, U1 p3 b
;; it is to accelerate or decelerate: h& Y) }, C- J6 ]
phase ;; keeps track of the phase7 u6 S+ s* ^2 n4 ]) X
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
~ d# M7 _( M! H3 l) k* i' l9 H current-light ;; the currently selected light p+ Q6 k/ K" ~6 g
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;; patch agentsets1 J5 [5 S, u1 e+ m
intersections ;; agentset containing the patches that are intersections8 F7 C) T+ i" g) p4 h1 |0 p
roads ;; agentset containing the patches that are roads
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turtles-own
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speed ;; the speed of the turtle
4 O" o! L/ @/ |: \" { up-car? ;; true if the turtle moves downwards and false if it moves to the right* I% m1 \. d+ ]/ v& K
wait-time ;; the amount of time since the last time a turtle has moved; B2 e7 ]" z6 c7 J* P, k& S: H
]
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patches-own( M4 b$ d$ V4 {0 B: \% u' Z0 l" ?
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intersection? ;; true if the patch is at the intersection of two roads% e& Y' s7 B5 l1 _
green-light-up? ;; true if the green light is above the intersection. otherwise, false.) S: i7 I3 i: A! A% F( @
;; false for a non-intersection patches.6 y7 ^3 I5 b8 }) J
my-row ;; the row of the intersection counting from the upper left corner of the
7 Y* e8 O c. r! g+ A0 ^" u9 r ;; world. -1 for non-intersection patches.3 `9 P8 C" N: v5 v
my-column ;; the column of the intersection counting from the upper left corner of the
* o/ K, l/ y/ H ^' w. Z ;; world. -1 for non-intersection patches.
- _/ O/ K: O8 h8 E8 D' v3 T my-phase ;; the phase for the intersection. -1 for non-intersection patches.2 x$ ]1 F) t) u/ a+ K; w
auto? ;; whether or not this intersection will switch automatically.0 j; p7 m9 Z4 f+ `/ v
;; false for non-intersection patches.: ]0 K9 W% F1 }/ ^, o9 \
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7 G* _2 a- J, w0 w$ O e' x;;;;;;;;;;;;;;;;;;;;;;
. F: V, v3 o$ O8 v9 v9 n;; Setup Procedures ;;
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5 p1 F4 N2 o% F) s% i0 w- X;; Initialize the display by giving the global and patch variables initial values.
- W4 y) W2 W+ i# @4 m a;; Create num-cars of turtles if there are enough road patches for one turtle to0 z4 d# I0 g9 q3 U4 D$ h
;; be created per road patch. Set up the plots.- x+ y4 G; X4 n/ o2 L& W
to setup
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setup-globals- ]/ p: g4 {& U- A9 k- Z: t
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;; First we ask the patches to draw themselves and set up a few variables
9 u8 m1 @ h( W" E8 n setup-patches
+ q' I6 u+ e( U6 b& }% U* z1 Q make-current one-of intersections
, p/ ~1 w* c7 ^; q" O! Y* {$ G label-current
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set-default-shape turtles "car". {: I. A; U7 O$ v$ F6 p& O
; b( v' a8 |$ j1 e if (num-cars > count roads)' X) Z8 i J7 c' f) B3 _
[
6 _* d% S" T2 Q* R' I2 E user-message (word "There are too many cars for the amount of "
4 Z, C9 J, I. C7 S* F3 O5 r "road. Either increase the amount of roads "
5 E8 D9 g' p( w+ ^4 a7 y "by increasing the GRID-SIZE-X or "
- @/ h3 K. e+ m# k% A8 O" u "GRID-SIZE-Y sliders, or decrease the "& N7 l; d1 a6 F9 a/ i6 G5 G% ^
"number of cars by lowering the NUMBER slider.\n"6 b9 Q) p2 ?1 l8 y/ `9 C
"The setup has stopped.")
) U" \8 {0 S, O/ Y" W stop
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) r- C5 ]# S `% Q7 m ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
* C8 O- f4 R) {/ m3 ~ crt num-cars/ h9 \' e2 `7 Q- R& i) p, b
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setup-cars+ W! ]) z0 {% H# ?. _
set-car-color
& }4 x+ o4 ^( [) r1 I/ g record-data. H" G' y# F( K: S) Z. q
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;; give the turtles an initial speed
( j$ K. B1 ^6 F6 ]9 v# v ask turtles [ set-car-speed ]0 Z, d* }# D# D( H5 W: o$ i i
0 E2 ^! a6 j3 t$ t/ S. v& D2 m" q reset-ticks- S- J8 ?/ a2 j) f2 d, H
end
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;; Initialize the global variables to appropriate values
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* u+ N4 \6 t* M C& X+ J set current-light nobody ;; just for now, since there are no lights yet
; T9 H1 z( b/ x( S set phase 0
3 L5 B+ J' M2 ^% b* ] set num-cars-stopped 0% n3 \6 K) V. X3 {
set grid-x-inc world-width / grid-size-x
3 u* g& v* H3 ?: K! U3 o 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: U5 d* s7 P; @' {3 ~5 \; g
set acceleration 0.099$ b; W9 i8 T+ @2 h5 O) ?$ L
end
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3 f) H3 v0 Q$ O/ m( D;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 Z. j8 H/ r9 @) u* x, n# K8 i% o;; and initialize the traffic lights to one setting
- u! l. B2 x0 Q* A' o- t# `& nto setup-patches
, | X7 Y, g9 |! h% h% r& y* t ;; initialize the patch-owned variables and color the patches to a base-color
8 Z0 [' u3 z* n, ^ ask patches, F% o. R `& l' V1 _
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+ b1 n0 `5 ^+ x+ L, I6 ]7 D set intersection? false v- G9 e* D8 g \
set auto? false
" l O2 a$ Q7 O' p# B* X set green-light-up? true
4 W" t' j* {3 w1 g set my-row -1
; s3 a. U& L s( k! G+ z set my-column -1
. w* ~3 d4 x5 G; D7 w# y/ d9 S set my-phase -1
+ I4 }( Q- w+ v2 C9 O+ W+ K set pcolor brown + 3
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8 @4 v- c+ A; B- j- ]) Z8 _+ Y r ;; initialize the global variables that hold patch agentsets8 A( ` r/ l5 u3 v
set roads patches with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]+ N2 H9 P, M; I2 Q8 H
set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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+ V+ h. O9 m$ P! k ask roads [ set pcolor white ]- ^# j, @% X; m; F
setup-intersections" K3 ~2 G8 h. X: s- \$ ]6 A; n: |
end
' B& Y' `8 }8 b& B; j9 a其中定义道路的句子,如下所示,是什么意思啊? j, ~3 c; G1 M' s" b5 e: x
set roads patches with
4 { Q2 Q- [( b' D1 N [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or ~% u& M: `' B+ J1 c5 g
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]% v) H- H: \' p5 \" A' y- U
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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