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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。- T8 M% A+ C5 _6 P0 E
netlogo自带的social science--traffic grid这一例子当中,
/ y3 g+ V8 z7 W1 k2 L& Fglobals9 k* G4 s$ \% e. @3 k: y* ~+ G
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grid-x-inc ;; the amount of patches in between two roads in the x direction
7 p ^9 D8 C1 {' o: ^6 C3 ~ grid-y-inc ;; the amount of patches in between two roads in the y direction
' B# {% u: w0 o" l- L1 Z acceleration ;; the constant that controls how much a car speeds up or slows down by if' h3 E' j% k$ X9 i! e" r! F
;; it is to accelerate or decelerate
^$ e. Y5 l% D/ L+ k/ m! g phase ;; keeps track of the phase
4 v1 u+ H" Q& @ num-cars-stopped ;; the number of cars that are stopped during a single pass thru the go procedure
7 t8 G! a* e; X$ u2 _7 w current-light ;; the currently selected light
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;; patch agentsets& Y" g8 f' P, [1 v
intersections ;; agentset containing the patches that are intersections" z8 }/ m- F) j0 w& R$ ]
roads ;; agentset containing the patches that are roads4 E! I; z+ t. s! b7 k. n$ `
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/ g0 z( x& y: K, Sturtles-own
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" | H" }+ k" z$ P6 d# r speed ;; the speed of the turtle7 `7 r* o* b+ o" T
up-car? ;; true if the turtle moves downwards and false if it moves to the right" a0 a5 ~6 Z! p) z, k' ?
wait-time ;; the amount of time since the last time a turtle has moved4 I( x7 l7 z6 C9 a9 B
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1 h3 @# B* P; E. E4 e# |0 y8 ~5 xpatches-own- t# F: Y$ W) T7 S' z7 X9 h
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intersection? ;; true if the patch is at the intersection of two roads9 n9 `8 q* w! i, }! Z
green-light-up? ;; true if the green light is above the intersection. otherwise, false. M b3 _6 g! R) ?
;; false for a non-intersection patches.; [8 x# n1 I- X: b; E, M
my-row ;; the row of the intersection counting from the upper left corner of the
5 q' K/ `8 Y1 j4 S( T) x ;; world. -1 for non-intersection patches.3 k* r! z7 i0 }3 t% b$ Z
my-column ;; the column of the intersection counting from the upper left corner of the
4 K5 l) h; Y9 [8 b9 b ;; world. -1 for non-intersection patches.
5 U7 U" O$ ~) t. ^; l1 S my-phase ;; the phase for the intersection. -1 for non-intersection patches.
8 q+ |1 H$ e" d* q6 z auto? ;; whether or not this intersection will switch automatically.
R; A: P# g6 [0 \7 m- _4 u) u1 q ;; false for non-intersection patches.* Y# [9 P E; p3 Z" _# \) o$ G8 T1 u
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;;;;;;;;;;;;;;;;;;;;;;
1 @3 I6 [- R+ l" e8 e* j1 ]6 |;; Setup Procedures ;;9 j' c% Y1 W. W8 ~6 G
;;;;;;;;;;;;;;;;;;;;;;
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0 h! X7 T2 g5 ~$ @& };; Initialize the display by giving the global and patch variables initial values.
# T: @$ j+ i% Q3 d8 o m0 o;; Create num-cars of turtles if there are enough road patches for one turtle to
) N1 O6 z2 ]& h5 K5 _$ F9 p;; be created per road patch. Set up the plots.
0 D, o$ c) Q: Jto setup, _6 ~+ X3 f" q
ca
& N) j, p1 T4 ^ setup-globals4 T% B' `+ f3 d/ H0 v' J
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;; First we ask the patches to draw themselves and set up a few variables' o! u: N2 ^ j% [; P
setup-patches
* P2 F* M' R0 V; V5 T3 H: D make-current one-of intersections$ v$ Q) L" h6 W; a. s. P- I% S" H3 ~4 |" J
label-current
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set-default-shape turtles "car"
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. }9 U0 B% r, u h if (num-cars > count roads)
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. e4 I" h; a' t9 c2 I9 X1 |* B user-message (word "There are too many cars for the amount of "# v/ b4 D+ Z+ e c5 u% [1 e: u/ F
"road. Either increase the amount of roads "
2 @5 S2 L# P, s' U$ u- S2 v "by increasing the GRID-SIZE-X or " _. c5 p7 N3 [0 F
"GRID-SIZE-Y sliders, or decrease the "
- t0 Q8 H+ w9 I) w2 o0 b "number of cars by lowering the NUMBER slider.\n"
2 R+ y7 z" B A5 \0 m0 b; _ "The setup has stopped.")
* M0 i+ ^3 a& d+ y; n* Y/ M stop0 s0 b- n8 @, w2 D
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7 `: P- Z: Y1 T' t* m& @ V ;; Now create the turtles and have each created turtle call the functions setup-cars and set-car-color
S2 c! d$ L& h crt num-cars/ e6 o7 v1 U/ U F
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& W7 K1 p8 }; ?8 [ setup-cars; e9 q) \, _$ y! ?+ G
set-car-color2 S2 o7 l% V9 k* l2 ^& Y! F
record-data. X; i7 u+ ]! {+ N* J
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;; give the turtles an initial speed8 M# O( U7 v! O9 c& y* G7 w( T9 p
ask turtles [ set-car-speed ]
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reset-ticks
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;; Initialize the global variables to appropriate values1 _5 q. @" a% S8 b2 w* V
to setup-globals T) {; c+ s; s6 \. t" T
set current-light nobody ;; just for now, since there are no lights yet4 R* \* R5 i) W$ Y* g
set phase 0+ n0 F. k) H- H0 k9 A
set num-cars-stopped 0/ Y4 _& @) v M3 B
set grid-x-inc world-width / grid-size-x
% \% M5 p7 m6 E4 ~( m* N set grid-y-inc world-height / grid-size-y% q* ]# J1 w; F9 n6 `
' y1 p1 c9 w. S6 c$ t6 c ;; don't make acceleration 0.1 since we could get a rounding error and end up on a patch boundary7 X8 T( p& c( f; k3 Y
set acceleration 0.099
i1 Q: h! b2 B8 S4 y$ ?end' }9 B( Q( I; v; Y) A
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;; Make the patches have appropriate colors, set up the roads and intersections agentsets,
8 ^# d. x' f! O3 @' u; Q;; and initialize the traffic lights to one setting7 \/ P6 m" q4 `; m3 j# t
to setup-patches4 _* F; @. t$ U$ K
;; initialize the patch-owned variables and color the patches to a base-color
0 |" P0 @2 [( e; J ask patches+ }* w, z0 }* Z8 R/ `; d
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set intersection? false
* U1 X2 V8 U- A1 Q& y& c3 B set auto? false; {6 F7 J9 G, d: V9 u
set green-light-up? true1 H7 c; T8 L4 o# [
set my-row -1* i: @9 ]9 Y) B3 R) e, o i
set my-column -1
$ W/ L# R$ }3 l5 @% ` set my-phase -1
0 s: O! p- X2 j$ q3 k6 E* _4 T set pcolor brown + 35 p6 C) K" ~) N5 H; s
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9 d9 ^$ E( }4 Z1 B8 A5 k* h! v ;; initialize the global variables that hold patch agentsets0 ?& ?8 @, |5 N1 l4 f
set roads patches with( E2 Z' t- Z" K
[(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or3 _1 b+ W- f Y# ~1 O
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]
@- }+ @ l8 A2 D% W) M set intersections roads with
7 O5 v( W6 g! ?4 p6 L/ y( { [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) and
7 o; V/ E9 s, E: L8 r7 G (floor((pycor + max-pycor) mod grid-y-inc) = 0)]
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* {) \2 B/ J3 W* e4 _) r! t2 K ask roads [ set pcolor white ]
$ Y( x& @4 V+ I* o3 _/ b setup-intersections9 q- C. D/ c2 y/ O. J
end/ J' r7 Y2 i9 @& y3 R
其中定义道路的句子,如下所示,是什么意思啊?& _$ `/ M' a5 O2 t/ `
set roads patches with
8 d c3 y" L. O1 o) u [(floor((pxcor + max-pxcor - floor(grid-x-inc - 1)) mod grid-x-inc) = 0) or- L" R2 B( a# M8 V
(floor((pycor + max-pycor) mod grid-y-inc) = 0)]7 b1 p" l! ?% a0 q
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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