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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。( T4 [( u8 G$ F; i; {$ N6 U0 b' }; Z
netlogo自带的social science--traffic grid这一例子当中,
: {3 [9 q" @1 E2 w+ a/ sglobals
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$ ~5 W6 q/ ?: U$ ~* v8 M& ] grid-x-inc ;; the amount of patches in between two roads in the x direction' D7 O) T% c7 L, W) @2 S9 d, G- y$ t+ g
grid-y-inc ;; the amount of patches in between two roads in the y direction E& y$ M; N% O9 Q! r
acceleration ;; the constant that controls how much a car speeds up or slows down by if" P% W3 a o/ E; @0 X
;; it is to accelerate or decelerate
1 G# C0 L% Z9 ~$ V2 H phase ;; keeps track of the phase; [# C- f# u" P: c* I7 I6 A# \4 c
num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
1 l' |5 x; S% |( f, V6 X current-light ;; the currently selected light. Y4 y$ F, ?* K5 u, ^
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;; patch agentsets
3 W$ G+ ]9 b ^! U- ?1 L intersections ;; agentset containing the patches that are intersections8 M1 \, {8 k' g+ |8 D$ y
roads ;; agentset containing the patches that are roads
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turtles-own4 R j1 W+ [* H) ~4 C5 G1 ^
[
7 |! ~# K" f6 `4 x/ G speed ;; the speed of the turtle$ A) S8 k, K2 k0 Y
up-car? ;; true if the turtle moves downwards and false if it moves to the right1 A* K. S6 v! {2 a
wait-time ;; the amount of time since the last time a turtle has moved
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patches-own
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intersection? ;; true if the patch is at the intersection of two roads
2 v, v! j( E" N% M6 N3 m green-light-up? ;; true if the green light is above the intersection. otherwise, false.0 x {' }+ [- s* Y7 P: \
;; false for a non-intersection patches.* B7 P1 M C. p1 L- Q
my-row ;; the row of the intersection counting from the upper left corner of the
- q* }6 ~6 G. Z4 b/ ` ;; world. -1 for non-intersection patches.
/ x1 y, k3 U9 I- O: B my-column ;; the column of the intersection counting from the upper left corner of the
3 R( `' O4 H: W+ ^3 x- C. H; [ ;; world. -1 for non-intersection patches.3 o' h( \$ ` L1 _) A
my-phase ;; the phase for the intersection. -1 for non-intersection patches.
9 {& F8 m/ K$ V* G. w1 @ auto? ;; whether or not this intersection will switch automatically. y/ r% }; S, D$ P& ]6 ~- L6 V
;; false for non-intersection patches.3 W( \& {: U: v/ ?# @
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! Q. p' x+ I9 t0 O;;;;;;;;;;;;;;;;;;;;;;
8 H& u6 v$ c3 A* ~3 s# \9 Y: G& j;; Setup Procedures ;;) Q! P- R' [2 j+ L
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;; Initialize the display by giving the global and patch variables initial values.& R* D' X; z7 o; P) Q# [8 Z6 ~
;; Create num-cars of turtles if there are enough road patches for one turtle to
9 O/ G! A0 e9 ~, r1 o;; be created per road patch. Set up the plots.) ?, e1 p* E" G' G! c8 j6 O
to setup, j0 y/ o' i2 |% t f
ca
: x+ ^0 d5 U; m. o+ f setup-globals
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1 I% R! T3 E7 W8 g ;; First we ask the patches to draw themselves and set up a few variables; e6 t8 n* R. N/ o: f2 N8 ~- C& M
setup-patches& S, L& W' n9 f
make-current one-of intersections d. h/ G: Q0 {
label-current x7 `/ t# i/ D; ]8 Q. Z
8 J1 ~; ?/ d; _) U9 a( P) ?+ j set-default-shape turtles "car"
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if (num-cars > count roads)
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. r8 s1 Y) X' a- N" }) l user-message (word "There are too many cars for the amount of "
) A0 e0 d+ C8 t "road. Either increase the amount of roads "1 s o$ V) l4 w6 E0 S
"by increasing the GRID-SIZE-X or "
3 g) b4 a, A) p. ^ "GRID-SIZE-Y sliders, or decrease the "$ T6 O" `' B: [8 |+ C. c+ D* b
"number of cars by lowering the NUMBER slider.\n"
$ n9 }' I- [* V; Y8 e6 I, q "The setup has stopped.")3 O2 j$ p% M6 M: u
stop
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% }0 y8 d$ U4 p- l0 k ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
, Q7 n1 A k2 p" b8 z2 p crt num-cars
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setup-cars
" G8 t+ {9 D9 q+ g; b/ {& T set-car-color
4 R; v$ W F4 f, h record-data
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;; give the turtles an initial speed# r) F: @+ F+ Y0 J
ask turtles [ set-car-speed ]% C7 ~1 q& j% q
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reset-ticks( ^3 j$ i" C1 N
end& J, ~. o: ~4 M7 N, u
* k: l( I9 ~/ N;; Initialize the global variables to appropriate values+ p% N( _& s, T) }& S) W
to setup-globals
9 ~! ^8 b! `$ \& x3 {8 _ set current-light nobody ;; just for now, since there are no lights yet) ^- ~$ n- M" c" {7 H4 K3 b
set phase 0
) p: k1 k6 H$ A. Q set num-cars-stopped 0
$ F+ `7 M- v! V4 P7 r- g set grid-x-inc world-width / grid-size-x
! A2 C8 g# F- v5 v- v 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# {$ B ~: q* W- K T set acceleration 0.099
7 B1 Q( P- v9 H7 a& G( Iend( K- L. o) R; u
5 |; o) R* f7 D! F* v;; Make the patches have appropriate colors, set up the roads and intersections agentsets,1 ]5 W" j& m! K4 I" t" V6 a- w' W1 a H
;; and initialize the traffic lights to one setting
2 N) b) H B) l z, f6 rto setup-patches7 J- O! Q) H0 l4 R
;; initialize the patch-owned variables and color the patches to a base-color
: Q$ g! d. |1 A0 N4 p ask patches
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set intersection? false
( y! w" b$ H( ~, I } set auto? false2 g0 K5 I) R; J2 ?! v) D4 Y& K
set green-light-up? true
' J+ I( h8 i; m# @. G( |3 |! y set my-row -1% u1 ]& D3 O" @0 p' ]: i, Q
set my-column -14 D* R# \5 x2 S4 f; d6 ^2 A
set my-phase -17 a; t, [9 T/ `7 ^8 ~* _, N
set pcolor brown + 38 [: p# l- X% h) j* W) u: y
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;; initialize the global variables that hold patch agentsets6 l, b( c: A7 Q( V8 w
set roads patches with7 @: x, Z4 Q1 j/ V t, D. U
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or$ e- I# O/ U9 i5 o+ f1 b9 o
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
# t$ k2 N* a( A9 S" q& L set intersections roads with
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(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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ask roads [ set pcolor white ]
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end
, g5 _! r* F9 I7 P" s其中定义道路的句子,如下所示,是什么意思啊?0 d( L- _- p. @" T* e$ ?! w, c' y5 m
set roads patches with
1 G/ _5 U5 Z2 ? [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or! ]6 ^2 ^1 c4 e b/ }7 A1 e
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]) S0 W6 C" ~* ]9 f, f. Q$ R
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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