[Numpy-discussion] recarrays and lists of lists

Travis Vaught travis@vaught....
Sun Sep 11 14:44:29 CDT 2011


On Sep 11, 2011, at 2:58 AM, Robert Kern wrote:

> On Sun, Sep 11, 2011 at 00:30, Travis Vaught <travis@vaught.net> wrote:
>> Greetings,
>> 
>> Is there a particular reason why a list of lists can't be passed in to create a recarray given a particular dtype?
>> 
>> A list of tuples works fine.  I keep getting bitten by this and was thinking it should be an easy check/convert for an allowance for a row to be a list _or_ a tuple?
> 
> As a rule, tuples are considered "scalar" records and lists are
> recursed upon. This rule helps numpy.array() figure out which
> sequences are records and which are other sequences to be recursed
> upon; i.e. which sequences create another dimension and which are the
> atomic elements. Otherwise, it has to make some guesses and do some
> intelligent backtracking. It's not that intelligent.
> 
> -- 
> Robert Kern

Thanks for the explanation.  It makes a bit of sense -- at least to answer the question of what is being traded off here.  Looks like simplicity and performance, perhaps, is being chosen over my convenience.

Best,

Travis


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