Question

我需要把一个清单变成一个空洞的清单,如果它有两个带有某种财产的非重叠顺序。例如,在这种情况下,等于并且长度和幅度;= 2)

mm[{___, b1__, ___, b1__, ___}] := {} /; Length[{b1}] >= 2

or, for example 2 sublists, with a similarity function equal 0 and Legth = 4

mm[{___, b1__, ___, b2__, ___}] := {} /;
NeedlemanWunschSimilarity[{b1}, {b2}] == 0 && Length[{b1}] == 4 &&
Length[{b2}] == 4

and so on.....

For mathematica, guru who know internal algorithm, is there a faster way, perhaps using PatternTest (?) ?

Answer 1

I await a fuller description of what you are doing, but in the mean time:

mm2[{___, b1 : Repeated[_, {4}], ___, b2 : Repeated[_, {4}], ___}] := {} /; 
  NeedlemanWunschSimilarity[{b1}, {b2}] == 0

这里使用的是rel=“nofollow”Repeated,仅测试正确长度的顺序。

请具体说明最低和最长的序列长度,并注明<代码>[_,{min, max}]。