[R] Col names in a data frame

[Sarah Goslee]

Hi,

data.frame() checks names by default to ensure that column names are
legal, but there's an argument to change that.

>From ?data.frame()


check.names: logical.  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.

Sarah

On Thu, Jan 21, 2021 at 3:59 PM Bernard McGarvey
<mcgarvey.bernard using comcast.net> wrote:
>
> Here is an example piece of code to illustrate an issue:
>
> rm(list=ls()) # Clear Workspace
> #
> Data1 <- matrix(data=rnorm(9,0,1),nrow=3,ncol=3)
> Colnames1 <- c("(A)","(B)","(C)")
> colnames(Data1) <- Colnames1
> print(Data1)
> DataFrame1 <- data.frame(Data1)
> print(DataFrame1)
> colnames(DataFrame1) <- Colnames1
> print(DataFrame1)
>
> The results I get are:
>
>             (A)        (B)        (C)
> [1,]  0.4739417  1.3138868  0.4262165
> [2,] -2.1288083  1.0333770  1.1543404
> [3,] -0.3401786 -0.7023236 -0.2336880
>         X.A.       X.B.       X.C.
> 1  0.4739417  1.3138868  0.4262165
> 2 -2.1288083  1.0333770  1.1543404
> 3 -0.3401786 -0.7023236 -0.2336880
>          (A)        (B)        (C)
> 1  0.4739417  1.3138868  0.4262165
> 2 -2.1288083  1.0333770  1.1543404
> 3 -0.3401786 -0.7023236 -0.2336880
>
> so that when I make the matrix with headings the parentheses are replaced by periods but I can add them after creating the data frame and the column headings are correct.
>
> Any ideas on why this occurs?
>
> Thanks
>
>
> Bernard McGarvey
> Director, Fort Myers Beach Lions Foundation, Inc.
> Retired (Lilly Engineering Fellow).
>

-- 
Sarah Goslee (she/her)
http://www.numberwright.com