[R] Skipping lines and incomplete rows

[Uwe Ligges]

You actually jsut need to say what the comment char and what the 
na.strings are:

read.table(filename, sep=";", skip=3, header=TRUE, na.string="#N/A", 
comment.char="")

Uwe Ligges


On 10.07.2012 19:30, arun wrote:
> Hello Ravi,
>
> I was not aware that your dataset have special character "#" before NA.  If it was just plain NA, it would have worked.  So, It's not because of sep= ";".
>
> See below:
>
> #Without "#"
> dat1<-read.table(text="
>   Remove this line
>   Remove this line
>   Remove this line
>   Time;Actual Speed;Actual Direction;Temp;Press;Value1;Value2
>    ;[m/s];[°];°C;[hPa];[MWh];[MWh]
>   1/1/2012;0.0;0;NA;NA;0.0000;0.0000
>   1/2/2012;0.0;0;NA;NA;0.0000;0.0000
>   1/3/2012;0.0;0;NA;NA;1.5651;2.2112
>   1/4/2012;0.0;0;NA;NA;1.0000;2.0000
>   1/5/2012;0.0;0;NA;NA;3.2578;7.5455
>   ",sep=";",header=TRUE,fill=TRUE,skip=4,stringsAsFactors=FALSE)
>> dat1
>        Time Actual.Speed Actual.Direction Temp Press Value1 Value2
> 1                 [m/s]              [°]   °C [hPa]  [MWh]  [MWh]
> 2 1/1/2012          0.0                0 <NA>  <NA> 0.0000 0.0000
> 3 1/2/2012          0.0                0 <NA>  <NA> 0.0000 0.0000
> 4 1/3/2012          0.0                0 <NA>  <NA> 1.5651 2.2112
> 5 1/4/2012          0.0                0 <NA>  <NA> 1.0000 2.0000
> 6 1/5/2012          0.0                0 <NA>  <NA> 3.2578 7.5455
>
>
> #With "#": Reading data from the .txt file.
>
> # In the documentation (http://stat.ethz.ch/R-manual/R-devel/library/utils/html/read.table.html), comment.char="#" is an option in the read.table, but unfortunately it shows only blank columns after the first three columns.
>
>
> #I think Rui's method of reading header separately using readLines might be a good option.  Or if you know the columnheadings, then you can do this:
>
> dat2<-read.table("dat2.txt",skip=4,col.names=c("Time","Actual Speed","Actual Direction", "Temp","Press","Value1","Value2"),fill=TRUE,sep=";",comment.char="c")
>> dat2
>        Time Actual.Speed Actual.Direction Temp Press Value1 Value2
> 1                 [m/s]              [°]   °C [hPa]  [MWh]  [MWh]
> 2 1/1/2012          0.0                0  #NA   #NA 0.0000 0.0000
> 3 1/2/2012          0.0                0  #NA   #NA 0.0000 0.0000
> 4 1/3/2012          0.0                0  #NA   #NA 1.5651 2.2112
> 5 1/4/2012          0.0                0  #NA   #NA 1.0000 2.0000
> 6 1/5/2012          0.0                0  #NA   #NA 3.2578 7.5455
>
>
> A.K.
>
>
>
>
>
>
>
>
>
>
> ----- Original Message -----
> From: vioravis <vioravis at gmail.com>
> To: r-help at r-project.org
> Cc:
> Sent: Tuesday, July 10, 2012 1:41 AM
> Subject: Re: [R] Skipping lines and incomplete rows
>
> Thanks a lot Rui and Arun.
>
> The methods work fine with the data I gave but when I tried the two methods
> with the following semi-colon separated data using sep = ";". Only the first
> 3 columnns are read properly rest of the columns are either empty or NAs.
>
>
> **********************************************************************************************
> Remove this line
> Remove this line
> Remove this line
> Time;Actual Speed;Actual Direction;Temp;Press;Value1;Value2
> ;[m/s];[°];°C;[hPa];[MWh];[MWh]
> 1/1/2012;0.0;0;#N/A;#N/A;0.0000;0.0000
> 1/2/2012;0.0;0;#N/A;#N/A;0.0000;0.0000
> 1/3/2012;0.0;0;#N/A;#N/A;1.5651;2.2112
> 1/4/2012;0.0;0;#N/A;#N/A;1.0000;2.0000
> 1/5/2012;0.0;0;#N/A;#N/A;3.2578;7.5455
> ***********************************************************************************************
>
> I used the following code:
> dat1<-read.table("testInput.txt",sep=";",skip=3,fill=TRUE,header=TRUE)
> dat1<-dat1[-1,]
> row.names(dat1)<-1:nrow(dat1)
>
> Could you please let me know what is wrong with this approach?
>
> Thank you.
>
> Ravi
>
> --
> View this message in context: http://r.789695.n4.nabble.com/Skipping-lines-and-incomplete-rows-tp4635830p4635952.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help at 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 at 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.
>