Re: dataframe dereferencing

[Jaroslav Hajek]

On Fri, Sep 3, 2010 at 9:58 AM, CdeMills <address@hidden> wrote:
>
> I'm happy to see discussions about the dataframe concept. Regarding cell
> output format, the problems is as follows. After selecting some sub-range of
> size mxn, we may or may not need some extra information in order to rebuild
> a full dataframe for it. If we don't care, a cell array of size mxn, is just
> fine, this is the purpose of df.as.cell. If we care, then headers are added
> as two lines with column names and types as strings, and two columns with ID
> as unsigned int and row name as string. This compound table can't not just
> be further dereferenced, as the real content is offseted by two lines and
> two columns. The operations of sub-ranging and cell conversion can thus not
> be performed separately, this is the logic behind
> df.cell(some range). It results in one call to subsref, all the accessors
> being packed together.
>
> As a said, a dataframe should mimic as much as possible a matrix. If
> a=randn(3, 3), then you can't say
> cell(a). You have to explicitly call 'mat2cell'. This is why something
> cell(df) looks a bit strange to me, besides the problem of not separating
> subranging and output type conversion.
>
> Jaroslav, could you point us to some source of information about this
> concept of cs-list ?
>

doc>Data Containers>Comma separated lists

You can also check out the Matlab manual.

-- 
RNDr. Jaroslav Hajek, PhD
computing expert & GNU Octave developer
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz