[R] reading in ASCII files

Johann Petrak johann at ai.univie.ac.at
Mon Oct 1 09:50:49 CEST 2001

Mark Myatt wrote:

> Johann Petrak <johann at ai.univie.ac.at> writes:
>>- factors/levels are created automatically: often, the possible
>>  labels are known in advance and could immediately be
>>  converted. This would save a lot of memory and time for
>>  bigger files, I assume.
> You can use levels() and factor() to do this.
I know ... the point I wanted to make is that for 

very big files, this is an awful waste of memory
and time:
everything gets first stored as strings and only
after being read in gets converted to levels.
I am currently trying to understand the R source code
to do it another way: first convert a single
ASCII file to several binary coded column-files,
then read in those columns needed using readBin.
This should allow greates flexibility when
files are really big.


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