partial list sort
tjreedy at udel.edu
Wed Oct 9 20:30:17 CEST 2002
"jsaul" <jsaul at gmx.de> wrote in message
news:20021009163345.GD1157 at jsaul.de...
> * Eddie Corns [2002-10-09 14:48]:
> > Hint: list[x:y] is a COPY of the elements ie a new list.
> That's what I also thought initially.
Then you were correct and should have programmed with that in mind. I
gave you the fix you need. In Python, a slice of a builtin sequence
type is a separate sequence of the same type. Period. No argument
User-defined classes can do otherwise. In Numerical Python, a slice
of an array is not an array but a view into the same array. This is
for efficiency when working with mega-item arrays, but it is not
>But if in 'sort_components' I introduce the assignment
> list = 9
Irrelevant. The copy is a shallow (1 level) copy. Here you are
reaching into and modifying a 2-list that is a member of both the
original list and the slice extracted from it.
Terry J. Reedy
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