ENH/API: allow DataFrame constructor to better accept list-like collections (GH3783,GH4297)

[jreback]

closes #3783
closes #4297
related to #2305 (as now accept GeneratorType), but just convert to list, don't incrementally create the frame

[jtratner]

why couldn't you just remove the entire type check and just use is_list_like instead here?

[jreback]

DataFrame([DataFrame(dict(A = lrange(5)))])

this beauty here (which if you use just is_list_like) collapses it...maybe should just completely disallow this

[jtratner]

I think core.common.is_list_like(DataFrame(dict(A = lrange(5)))) returns True.

[jreback]

that's the problem, it needs to be initialized to an object array, rather than like a list-of-lists which is intialized differently

[jtratner]

ah - I see...could you check for PandasObjects first or something? (or add
not isinstance(data[0], (DataFrame, Panel))?) otherwise I guess it's fine

On Thu, Sep 12, 2013 at 9:08 PM, jreback notifications@github.com wrote:

In pandas/core/frame.py:

@@ -418,7 +418,8 @@ def init(self, data=None, index=None, columns=None, dtype=None,
if index is None and isinstance(data[0], Series):
index = _get_names_from_index(data)

•            if isinstance(data[0], (list, tuple, collections.Mapping, Series)):
  

•            if isinstance(data[0], (list, tuple, collections.Mapping,
  

•                                    collections.Sequence, Series)) and is_list_like(data[0]):
  

that's the problem, it needs to be initialized to an object array, rather
than like a list-of-lists which is intialized differently

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Reply to this email directly or view it on GitHubhttps://github.com//pull/4829/files#r6339304
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[jreback]

no good solution either way; its basically checking if the input is 1-d or 2-d, hmm....let me try something..

[jtratner]

eh, I'm just not a fan of collections in general, because it's slowish, but this is probably the better option because it's more explicit, and, as @y-p notes, allows for objects to register themselves.

[jreback]

@jtratner that worked....now not dependent on the type per se only that its list-like and 1dim

[jreback]

@jtratner @cpcloud ?

[jtratner]

👍