[R] Casting lists to data.frames, analog to SAS

[hadley wickham]

> General Question: I assume the answer to the specific question is dependent
> on my understanding list objects and accessing their attributes.  Can anyone
> point me to a good, throrough treatment of these R topics?  Specifically how
> to read and interpret the output of the str(), and attributes() function,
> how to extract the values of the 'by' output object into a data frame, etc.?

It's not quite what you're asking for, but you might want to have a
look at the plyr package, http://had.co.nz/plyr, as an alternative.
Plyr provides a consistent set of methods for manipulating data frames
and lists to solve the same general problem that you struggled with in
your email - breaking up a complex structure, operating on each piece,
and then joining all the results back together.

Hadley

-- 
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