[R] Col names in a data frame

Jeff Newmiller
Thu, 21 Jan 2021 21:14:01 -0000

rm(list=ls()) is a bad practice... especially when posting examples. It
doesn't clean out everything and it removes objects created by the user.

Read ?data.frame, particularly regarding the check.names parameter. The intent
is to make it easier to use DF$A notation, though DF$`(A)` is usable if you are
somewhat experienced with R.

On January 21, 2021 12:58:44 PM PST, Bernard McGarvey <mcgarvey.bernard at
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).
>
>______________________________________________
>R-help at 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.

--
Sent from my phone. Please excuse my brevity.