Numbers as column names of data frames

Question

Is there a reason why R won't allow me to have a number as the column name of my dataframe?

Also noticed that if i do data.frame(XX) it adds an X to all the column headers that have numbers at the front.

score 32 · Answer 1 · answered Aug 06 '10 at 13:19

32

Works for me

data.frame(`1`=rnorm(3), `2`=head(letters,3), check.names=FALSE)
#        1 2
# 1 0.5019 a
# 2 1.1148 b
# 3 0.4787 c

answered Aug 06 '10 at 13:19

Marek

49,472
15
99
121

thanks. I understood about numbers, but it seems that some unicode text is disallowed. When I'm using a frame just for formatting, your suggestion comes in handy. – Steven R. Loomis Dec 16 '11 at 07:04

score 27 · Accepted Answer · edited Jan 02 '19 at 18:22

Yes, because R won't allow names of objects to start with numbers. If you were to call attach() with the data.frame, this would cause some issues.

data.frame (and read.table) function has the check.names parameter (default is TRUE)

If TRUE then the names of the variables in the data frame are checked to ensure that they are syntactically valid variable names and are not duplicated. If necessary they are adjusted (by make.names) so that they are.

From ?make.names:

A syntactically valid name consists of letters, numbers and the dot or underline characters and starts with a letter or the dot not followed by a number. [...] The character "X" is prepended if necessary.

Numbers as column names of data frames

2 Answers2

Linked

Related