[R] Writing out data

Paul Hiemstra paul.hiemstra at knmi.nl
Thu Feb 2 13:43:26 CET 2012

On 02/02/2012 11:40 AM, Thomas wrote:
> What is the best way to write out comma separated data, as a program
> is running (rather than waiting to the end using write.csv)? At the
> moment I'm doing this, but I guess it's not the most efficient. The
> data is in a column in the matrix postcount, and I'm using a loop to
> write out each of the 100 elements.
> for (j in 1:100)
> {
> cat(postcount[1,j], ",", file=filename, append=TRUE)
> }
> cat("\n", file=filename, append=TRUE)
> Thank you!
> Thomas
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write.csv also supports an append argument. Maybe that is faster than
using cat.


Paul Hiemstra, Ph.D.
Global Climate Division
Royal Netherlands Meteorological Institute (KNMI)
Wilhelminalaan 10 | 3732 GK | De Bilt | Kamer B 3.39
P.O. Box 201 | 3730 AE | De Bilt
tel: +31 30 2206 494


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