The first, [:], is creating a slice (normally often used for getting just part of a list), which happens to contain the entire list, and thus is effectively a copy of the list. The second, list(), is using the …

Nov 2, 2010 · When reading, list is a reference to the original list, and list[:] shallow-copies the list. When assigning, list (re)binds the name and list[:] slice-assigns, replacing what was previously …

The first way works for a list or a string; the second way only works for a list, because slice assignment isn't allowed for strings. Other than that I think the only difference is speed: it looks …

Given a dataframe, I want to groupby the first column and get second column as lists in rows, so that a dataframe like: a b A 1 A 2 B 5 B 5 B 4 C 6 becomes A [1,2] B [5,5,4] C [6] How do I do …

Apr 4, 2009 · Is the a short syntax for joining a list of lists into a single list ( or iterator) in python? For example I have a list as follows and I want to iterate over a,b and c.

Feb 25, 2015 · A list of lists would essentially represent a tree structure, where each branch would constitute the same type as its parent, and its leaf nodes would represent values.

However, it looks like tolist() is optimized for columns of Python scalars because I found that calling list() on a column was 10 times slower than calling tolist(). For the record, I was trying …

I can not find tge list of account passwords tgat I saved in google account

Nov 29, 2016 · You can't directly cast List to List because Java generics are invariant. This means that List is not the same as List, even though Customer is a subtype of Object.

Apr 17, 2013 · In C# if I have a List of type bool. What is the fastest way to determine if the list contains a true value? I don’t need to know how many or where the true value is. I just need to …