larry-discuss team mailing list archive

[Keith Goodman <kwgoodman@xxxxxxxxx>]

On Sun, Feb 7, 2010 at 7:40 PM,  <josef.pktd@xxxxxxxxx> wrote:
> On Sun, Feb 7, 2010 at 10:23 PM, Keith Goodman <kwgoodman@xxxxxxxxx> wrote:
>> On Sun, Feb 7, 2010 at 7:11 PM,  <josef.pktd@xxxxxxxxx> wrote:
>>
>>> If you want to go this way, you could have lixs :  lix with strings,
>>> and lixr : lix with repr , ... ?
>>> lix would be safe  because it uses the labels directly, the other ones
>>> are only recommended in restricted cases where the string (or other)
>>> representation makes sense.
>>
>> Too confusing with two I think.
>>
>>> if you want to allow slicing i.e. `:`  then I think lix would need to
>>> use its __getitem__ instead of __call__ or __init__
>>> lar1[1:4, lix['msft', google], lixs['2010-02-01':]   or lar1[1:4,
>>> lix[['msft', google]], lixs['2010-02-01':] ?
>>
>> lar1[lix(date)]: will work. So will lar[lix(date1):lix(date2)]
>>
>> Allowing slices slows things down because now we have to look instead
>> each slice object (slice.start, slice.stop) for lix object and if
>> found convert them.
>
> I wouldn't mix lix and regular array slices or indices for the same
> axis. I would restrict it to if either one of (slice.start,
> slice.stop) are lix then both are interpreted as labels.
>
> either lar[lix[date1:date2],:]   or   lar[lix(date1):lix(date2), :]
> but not lar[lix(date1):-3]

How come? Seems handy to me.


>
>>
>>> I don't know if lix should hold some code for conversion from label
>>> representation to indices, or be just an identifier for use in
>>> larry.__getitem__
>>
>> Yeah, a method getindex that takes label as input, perhaps. larry's
>> getitem is already getting harry, so keeping the code in lix instead
>> of adding yet more code to getitem might be a good idea. Or make a
>> function in util.misc like a did for string indexing.
>>
>>> Josef
>>>
>>
>