Hi r-help-boun...@r-project.org napsal dne 09.05.2011 16:07:27:
> Nilza BARROS <nilzabar...@gmail.com> > Odeslal: r-help-boun...@r-project.org > > 09.05.2011 16:07 > > > Dear R users, > > I am reading data from a file where there are some missing that are > represented by -9999.00. > I am using the command below. > =====My original data =========== > > PARM = TMPC;T12X;T12N;DWPC;PALT;SKNT;DRCT;P24M;CLCL > > > STN YYMMDD/HHMM TMPC T12X T12N DWPC PALT > SKNT > DRCT P24M CLCL > 820420 110429/1200 22.50 -9999.00 22.40 22.20 -9999.00 > 0.00 > 0.00 84.00 4.00 > 820980 110429/1200 26.90 -9999.00 23.40 24.10 1010.20 > 2.91 > 360.00 2.00 6.00 > 821130 110429/1200 24.30 -9999.00 23.30 23.70 -9999.00 > 1.94 > 230.00 3.00 4.00 > 821410 110429/1200 24.40 -9999.00 23.70 24.20 1011.80 > 2.91 > =========== > > dados<-read.table > ("2011042912_teste.dat",sep='',fill=TRUE,na.strings="-9999.00",skip=4) > head(dados) > V1 V2 V3 V4 V5 V6 V7 V8 group > 1 820420 110429/1200 22.5 NA 22.4 22.2 NA 0.00 1 > 2 0 84.00 4.0 NA NA NA NA NA 1 > 3 820980 110429/1200 26.9 NA 23.4 24.1 1010.2 2.91 2 > 4 360 2.00 6.0 NA NA NA NA NA 2 > 5 821130 110429/1200 24.3 NA 23.3 23.7 NA 1.94 3 > 6 230 3.00 4.0 NA NA NA NA NA 3 > ============= > After some procedures a have the data as below: > > head(Alldados) > > > Station_NO date1 T_2M TMAX_2M TMIN_2M TD_2M PS FF_10M DD_10M > 1 820420 110429/1200 22.5 NA 22.4 22.2 NA 0.00 0 > 2 820980 110429/1200 26.9 NA 23.4 24.1 1010.2 2.91 360 > 3 821130 110429/1200 24.3 NA 23.3 23.7 NA 1.94 230 > 4 821410 110429/1200 24.4 NA 23.7 24.2 1011.8 2.91 270 > 5 821450 110429/1200 28.2 NA 21.1 25.8 1008.8 0.00 0 > 6 821810 110429/1200 23.3 NA 22.8 22.9 1001.6 0.00 0 > TOT_PRCP CLCL date2 > 1 84.00 NA 2011042912 > 2 2.00 NA 2011042912 > 3 3.00 NA 2011042912 > 4 12.00 NA 2011042912 > 5 6.00 NA 2011042912 > 6 38.00 NA 2011042912 > > But I need to feed my database. These missings should be represented by > NULL. > I mean, all "NA" should be replaced by "NULL" in my database. > I am trying the command below to pick up the rows and columns with NA but I > don't know how to fill the original data : > > which(is.na(Alldados),arr.ind=TRUE) > > But I don't know how to replace each NA with NULL. I tried using as.null but > NA is not replace at all. Why do you want that? NULL is reserved for objects which emerged from undefined function results. See its help page. As such you can not have vector of NULLs. > rep(NULL, 10) NULL > rep(NA, 10) [1] NA NA NA NA NA NA NA NA NA NA Maybe you want to replace NA with zero. If yes Alldados[is.na(Alldados)]<-0 could be what you want. Regards Petr > > I hope someone could help me. > > Best Wishes, > Nilza Barros > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. ______________________________________________ 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.