Question

Very simple question. I am using an excel sheet that has two rows for the column headings; how can I convert these two row headings into one? Further, these headings don’t start at the top of the sheet.

Thus, I have DF1

Temp Press  Reagent  Yield A  Conversion etc
degC bar    /g       %        %             
1    2      3        4        5          
6    7      8        9        10

and I want,

Temp degC Press bar  Reagent /g  Yield A % Conversion etc
1         2          3           4         5          
6         7          8           9        10

Using colnames(DF1) returns the upper names, but getting the second line to merge with the upper one keeps eluding me.

Answer 1

Using your data, modified to quote text fields that contain the separator (get whatever tool you used to generate the file to quote text fields for you!)

txt <- "Temp Press  Reagent  'Yield A'  'Conversion etc'
degC bar    /g       %        %             
1    2      3        4        5          
6    7      8        9        10
"

this snippet of code below reads the file in two steps

1. First we read the data, so skip = 2 means skip the first 2 lines
2. Next we read the data again but only the first two line, this output is then further processed by sapply() where we paste(x, collapse = " ") the strings in the columns of the labs data frame. These are assigned to the names of dat

Here is the code:

dat <- read.table(text = txt, skip = 2)
labs <- read.table(text = txt, nrows = 2, stringsAsFactors = FALSE)
names(dat) <- sapply(labs, paste, collapse = " ")

dat
names(dat)

The code, when runs produces:

> dat <- read.table(text = txt, skip = 2)
> labs <- read.table(text = txt, nrows = 2, stringsAsFactors = FALSE)
> names(dat) <- sapply(labs, paste, collapse = " ")
> 
> dat
  Temp degC Press bar Reagent /g Yield A % Conversion etc %
1         1         2          3         4                5
2         6         7          8         9               10
> names(dat)
[1] "Temp degC"        "Press bar"        "Reagent /g"      
[4] "Yield A %"        "Conversion etc %"

In your case, you’ll want to modify the read.table() calls to point at the file on your file system, so use file = "foo.txt" in place of text = txt in the code chunk, where "foo.txt" is the name of your file.

Also, if these headings don’t start at the top of the file, then increase skip to 2+n where n is the number of lines before the two header rows. You’ll also need to add skip = n to the second read.table() call which generates labs, where n is again the number of lines before the header lines.