[R] how to load data frame where numeric will be numeric instead of character

[Bert Gunter]

Agreed!

However, there may still be a problem, as read.table() ordinarily would
read numeric columns correctly (via type.convert()) without the colClasses
specification.
So I would suspect that her "numeric" columns contain some non-numeric
detritus (perhaps "," or some NA symbol). But of course, who knows? -- and
she should follow David's advice to read the docs anyway.


Bert Gunter

"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )


On Mon, Jun 1, 2020 at 3:19 PM David Winsemius <dwinsemius using comcast.net>
wrote:

>
> On 6/1/20 2:17 PM, Ana Marija wrote:
> > HI David,
> >
> > this is the problem:
> >
> > > NEP <- read.table("gokind.nephropathy.fin",
> > header=T,stringsAsFactors=FALSE)
> > > sapply(NEP,class)
> >         Chr          BP      Marker         MAF          A1        A2
> > "character" "character" "character" "character" "character" "character"
> >   Direction      pValue           N
> >
> > So even entries like Chr, BP, MAF....are characters while they should
> > be numeric
> > > head(NEP)
> >   Chr        BP           Marker      MAF A1 A2 Direction pValue    N
> > 1  10 100000625 10:100000625:A:G   0.4156  G  A         + 0.484813 1641
> > 2  10 100000645 10:100000645:A:C 0.216027  C  A         +  0.73597 1641
> >
> >
> > Can you please tell me what colClasses=colClassvec suppose to do?
>
>
> I could tell you, but I think instead that you should read the
> documentation for the `read.table` function.
>
>
> --
>
> David
>
> >
> > Thanks
> > Ana
> >
> > On Mon, Jun 1, 2020 at 4:13 PM David Winsemius <dwinsemius using comcast.net
> > <mailto:dwinsemius using comcast.net>> wrote:
> >
> >
> >     On 6/1/20 1:37 PM, Ana Marija wrote:
> >     > Hello,
> >     >
> >     > I have a dataframe like this:
> >     >
> >     >    Chr        BP           Marker      MAF A1 A2 Direction
> >      pValue    N
> >     > 1  10 100000625 10:100000625:A:G 0.416562  G  A         -
> >     0.558228 1594
> >     > 2  10 100000645 10:100000645:A:C 0.215182  C  A         -
> >     0.880622 1594
> >     > ...
> >     >
> >     > which I load with:
> >     > NEU <- read.table("gokind.neuropathy.fin",
> >     header=T,stringsAsFactors=FALSE)
> >     >
> >     > and every column is numeric. How to say have all numeric ones
> >     stay numeric
> >     > like: Chr, BP, MAF, pValue, N
> >
> >
> >     I cannot figure out what the problem is. You say every column is
> >     numeric. It's not possible to have a column that contains the value
> >     "10:100000625:A:G" be numeric.
> >
> >
> >     If you meant to say the every column was character, then the answer
> >     might be:
> >
> >
> >     colClassvec <- rep("numeric",9)
> >     colClassvec[ c(3,5:7)] <- "character"
> >
> >     NEU <- read.table("gokind.neuropathy.fin",
> >     header=T,stringsAsFactors=FALSE, colClasses=colClassvec)
> >
> >     --
> >     David.
> >
> >     >
> >     > Thanks
> >     > Ana
> >     >
> >     >       [[alternative HTML version deleted]]
> >     >
> >     > ______________________________________________
> >     > R-help using r-project.org <mailto:R-help using r-project.org> mailing list
> >     -- To UNSUBSCRIBE and more, see
> >     > 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.
> >
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
>

	[[alternative HTML version deleted]]