Re: [Swarm-Support] Basic Swarm to HDF5 question

[Marcus G. Daniels]

Hi Kerimcan,

Another place to look is in the Swarm testsuite (in the Swarm source code).
For example tests/collections contrasts shallow (table-like) vs 
depth-first (tree-like) saving.

The HDF5 files created by those tests, e.g. shallowList.hdf and 
shallowMap.hdf can be loaded as data frames in R.  Maps will have row 
names attached and lists will not.  The deepMap.hdf and deepList.hdf 
will be lists of lists when loaded into R.  To load, use:

 library(hdf5)
 hdf5load("shallowMap.hdf")
 collections

Marcus

P.S. while the Swarm side of this is really random access, the R side is 
not.  It's necessary to load the whole file into memory.   That's not 
such a big deal these days with cheap RAM and 64 bit architectures, but 
it might be nice to rework the R module to do what the PgSQL module used 
to do, whereby one `attaches' to the database and then proxies to the 
objects are available as ordinary variables, but lazily evaluated for 
the sake of random access.