Huge data frames?
Hi, You should use scan() to read large ASCII tables. If you save a dataframe using save(), you get a binary file which works pretty fast. Note that similar problems arise if you try to save big dataframes in ASCII (you may consider my package savetable at http://www.obs.ee/~siim/savetable_0.1.0.tar.gz in order to do that). Best wishes, Ott
On Wed, 28 Aug 2002, Magnus Lie Hetland wrote:
|A friend of mine recently mentioned that he had painlessly imported a |data file with 8 columns and 500,000 rows into matlab. When I tried |the same thing in R (both Unix and Windows variants) I had little |success. The Windows version hung for a very long time, until I |eventually more or less ran out of virtual memory; I tried to set the |proper memory allocations for the Unix version, but it never seemed |satisfied :] | |I used read.table -- should I have used something else? Is it even |possible to work with this large files? I assume a memory-mapped |binary file would have been quite efficient (as opposed to an |in-memory parsed text file) -- is something like that even possible in |R? | | -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._