[R] Working around 256 byte variable names? + trouble opening large file

[RICHARD M. HEIBERGER]

If you are starting with an Excel file, then you should have R read
the xls file directly.
You should avoid the distortions often introduced by an intermediate
format such as .txt or .csv files.

I recommend using RExcel.  You can get it from CRAN with

install.packages("RExcelInstaller")
library(RExcelInstaller)
installRExcel()

For more details, go to http://rcom.univie.ac.at and click on the Wiki.

There are about 5 other packages that are also able to read xls files
directly into R.
Some of them can read Excel .xls files on operating systems that don't
have Excel.

Rich