[R] Performing Analysis on Subset of External data

[Laura Quinn]

Hi,

I want to perform some analysis on subsets of huge data files. There are
20 of the files and I want to select the same subsets of each one (each
subset is a chunk of 1500 or so consecutive rows from several million). To
save time and processing power is there a method to tell R to *only* read
in these rows, rather than reading in the entire dataset then selecting
subsets and deleting the extraneous data? This method takes a rather silly
amount of time and results in memory problems.

I am using R 1.9.0 on SuSe 9.0

Thanks in advance!


Laura Quinn
Institute of Atmospheric Science
School of Earth and Environment
University of Leeds
Leeds
LS2 9JT

tel: +44 113 343 1596
fax: +44 113 343 6716
mail: laura at env.leeds.ac.uk