Factoring as list

[compsystems]

Xcas has a command that returns a list of expressions, but without multiplicity?

1:
factors( x^4-1 ) returns
[x-1,1,x+1,1,x^2+1,1]

2:
factor( x^4-1 ) returns
(x-1)*(x+1)*(x^2+1)

3:
split( x^4-1, x) returns
Error =(

x^4-1 ->
[x-1,x+1, x^2+1]

[parisse]

you can easily write a user program from the output of factors to do that.

[compsystems]

Code : Tout sélectionner

   splits(pol):=
  {
   fs:=factors(pol);
   sz:=size(fs);
   return seq('fs[k-1]',k,1,sz,2);
  }

1:
factors(x^4-1) returns
[x-1,1,x+1,1,x^2+1,1]

2:
splits(x^4-1) returns
[x-1,x+1,x^2+1]

3:
split(x^4-1,[x,y]) trick
[(x-1)*(x+1)*(x^2+1), 1]


An idea, I like that commands embedded in the system
add a Full keyword, to denote total separation, As does matlab
https://www.mathworks.com/help/symbolic/factor.html

4:
split(x^4-1,x,'full')
[x-1,x+1,x^2+1]