On 06/10/2019 8:23 a.m., vod vos wrote:
> The problem is aa, bb and cc all in a single csv file
> contains no blank line.
So what steps do you need, and which of them do you need help with?
Duncan Murdoch
> The single csv file like list output.
>
> aa(cm)
> 1, 2 , 3,
> bb(mm)
> 1, 2, 3,
> 4, 5, 6,
> 7, 8, 9,
> cc(mm)
> 3, 4, 5,
> 7, 5, 9,
> 6, 5, 8,
>
>
>
> ---- 在 星期日, 06 十月 2019 05:08:41 -0700 Duncan Murdoch <murdoch.duncan using gmail.com> 撰写 ----
> > On 06/10/2019 7:29 a.m., vod vos via R-help wrote:
> > > I got hundreds of csv files. The real formats in each csv file are as follows:
> > >
> > > aa(cm)
> > > 1, 2 , 3,
> > >
> > > bb(mm)
> > > 1, 2, 3,
> > > 4, 5, 6,
> > > 7, 8, 9,
> > >
> > > cc(mm)
> > > 3, 4, 5,
> > > 7, 5, 9,
> > > 6, 5, 8,
> > >
> > > How can I use read.table or read.csv to convert the csv files
> > > to a tidy data frame format as follow:
> > >
> > > aa, bb, cc
> > > 1, 1, 3
> > > 1, 2, 4
> > > 1, 3, 5
> > > 2, 4, 7
> > > 2, 5, 5
> > > 2, 6, 9
> > > 3, 7, 6
> > > 3, 8, 5
> > > 3, 9, 8
> > >
> > > many thanks.
> >
> > You'll need more than those two functions to do the transformation you
> > want. To work out what you need, write out the process in detail in
> > English (or another natural language), not in code. For example:
> >
> > 1. Read aa from file 1.
> > 2. Read bb from file 2.
> > 3. Read cc from file 3.
> > 4. Expand all vectors to the same length.
> > 5. Combine them into a single dataframe.
> >
> > Then work out each step separately. I think you'll want to use
> > something like scan("filename", skip = 1, sep = ",") in steps 1, 2, and
> > 3, but this will add NA values at the end of each line because of the
> > final comma, so you could do this:
> >
> > aa <- scan("file1", skip = 1, sep = ",")
> > aa <- aa[!is.na(aa)]
> >
> > and similarly for the others.
> >
> > I don't know the rules for expanding that you'll need in your real data,
> > but for your example step 4 could be
> >
> > aa <- rep(aa, each = 3)
> >
> > Then step 5 could be
> >
> > result <- data.frame(aa, bb, cc)
> >
> > Duncan Murdoch
> >
>