我新调试好的程序如下,应该是对的,供参考# w; ^0 ?6 I7 K0 x6 v2 d* c3 L7 x0 b
因为特殊要求,这里的边的长度是二维座标内的空间距离( x e" ^6 q- n# G8 A1 P
, W" `+ P4 a' H* O' j6 R) \# uto find-distance9 N, Y- a6 \5 ~0 y
let i 0$ L" J; Z& J. w! T: I
let j 0 ; j7 |: C; O" p let nodedistance 04 Z7 j! Y) c0 Z9 B* S) p% m
let linknumber 02 y" B( X8 k- A5 I& b- d3 K
) r `% {/ q& {! t% t2 x while [j < count turtles] " L& U- I4 E& P [* Y! M6 ~4 g( `2 a! O0 D
while [i < count turtles]% \" J2 P; M. L( r& e
[ if link-neighbor? turtle i 4 P. ?9 }1 w* y" c [ask turtle j [set nodedistance nodedistance + distance turtle i] # R% J9 j# P/ D ask turtle j [set linknumber linknumber + count [link-neighbors] of turtle i]# b+ w5 I& V8 o s2 m; j' d
] 9 q$ X; K& k% u& w. n, H! ? e set i i + 1 ! E8 p) f4 S$ s! X- a* P: N i ] 8 e- W* n6 P7 y. k7 Q- o
set j j + 1 & B5 b- O# b, _! I$ \ ]/ L: `( Q) i+ }3 x) d/ z
set average-path-length nodedistance / (linknumber * 2)0 S9 j( z: w; R0 x
end