PatternClass-2.4.2/lib/decomp.gi

2 ##  This program is free software: you can redistribute it and/or modify
7 ##  This program is distributed in the hope that it will be useful,
25 ## x<n (n=length of the permutation) in the permutation that is a rank encoding,
26 ## to check whether perm is a plus-decomposable permutation.
28 ## Side Note: The permutation [1,2] (encoded as [1,1]) is seen as a
30 ## a permutation, eventhough it is also a simple permutation.
65 ## IsMinusDecomposable checks whether the permutation perm is minus decomposable
66 ## by checking whether the complement of the permutation is plus decomposable.
68 ## Side Note: The permutation [2,1] (encoded as [2,1]) is seen as a
70 ## a permutation, eventhough it is also a simple permutation.
104 ## IsSimplePerm checks whether the permutation perm is simple, i.e. there are no
184 ## LdkAut is an auxiliary function to build an intermediate automaton, which
222 ## LAut is another auxiliary function to build an intermediate automaton, which
224 ## permutations of a class. LAut is the union of LdkAut over the range of d in
244 ## MinusDecomposableAut finds the regular language that is build by all simple
385 ## IsInterval takes in any sublist of a permutation and checkes whether it is
412 ## If a plus- or minus-decomposable permutation is input, then the decomposition
417 local p,i,j,a,temp,simp,min,max;
428 #Building the intervals here. i is start of interval and counting up
429 #j is end of interval, counting down for each i, to get the maximal
458 simp:=OnTuples([1..Length(temp)],Sortex(temp));
460 Add(a,simp,1);