On Feb 9, 2011, at 7:15 AM, PtitBleu wrote:
Hello,
I have a text file with one column containing long number but stored
as
string.
I download the file with read.table (and colClass) and the first row
of this
column is :
"095842087016731010"
As I need to make some calculations with these numbers, I tried to
convert
them using as.numeric.
But then I get
as.numeric("095842087016731010")
95842087016731008
Your number is many powers of ten above the maximum possible integer
value 2*10^9. So you are seeing the floating point number that
resulted from coercion, and R does not have arbitrary precision
arithmetic in its base repertoire.
I understand the disappearing of the first 0 but I don't understand
the
substitution of the last 0 by 8.
Is there a way to avoid that ?
There is a package that handles bignums, Brobdingnag.
. And there is interfaces to the symbolic algebra system, Yacas.
But.... Do you really need arbitrary precision?
Thanks in advance,
Ptit Bleu.
--
David Winsemius, MD
West Hartford, CT
______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
