This is how Gretl exports to csv
Create text file (tab between columns)
year         gdp
2000 8010672
2001 8070670.31
2002 8198842.23
2003 8421918.34
2004 8776525.02
2005 9089701.34
2006 9413052.38
2007 9709513.84
2008 9674648.114
2009 9333377.657
2010 9615405.926
2011 9782251.723
2012 9974404.718 
import in gretl
run
logs gdp
genr gdp10=gdp/10
genr gdp100=gdp/100
genr gdp1000=gdp/1000
genr gdp10000=gdp/10000

export to CSV (top lines)

obs    gdp                                  l_gdp                 gdp10                             gdp100                      gdp1000                     gdp10000
2000 8010672.000000000000 15.8962852107 801067.199999999953  80106.720000000001  8010.672000000000  801.0672000
2001 8070670.309999999590 15.9037470988 807067.030999999959  80706.703099999999  8070.670310000000  807.0670310
           (heap of junk in last dig.)    (func. 12 dig. +(.))                                                                                                                             (no junk digits)

For example, my problem with R3.1 was caused not by large numbers, but by large number of junk digits in gdp
May be it would be better to set 16 symbols for a number (15+1) and set "e" format for numbers greater than some N, say 10^6?






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