Unicode in column names

Question

Just like in title, I'd like to put some Unicode characters to column names of data frame.

Toy example:

df<-data.frame(x=1:3, y=4:6)
 
(nm<-c('x\u00b2', 'y\u2082'))
"x²" "y₂"
 
colnames(df)<-nm
 
df
  x2 y2
1  1  4
2  2  5
3  3  6

As you can see, sub- and supercripts are converted to "ordinary" digits.

One more try:

 (nm<-c('x\u03B2', 'y\u2082'))
 "xβ" "y₂"
 
 colnames(df)<-nm
 
 df
  xß y2
1  1  4
2  2  5
3  3  6

Now greek β is converted to german ß (despite my Windows locale is Poland...)

Finally, greek gamma seems to be left as it is:

 (nm<-c('x\u03B3', 'y\u2082'))
 "xγ" "y₂"
 
 colnames(df)<-nm
 
 df
  x<U+03B3> y2
1         1  4
2         2  5
3         3  6
Warning message:
In do.call(data.frame, c(x, alis)) :
  unable to translate 'x<U+03B3>' to native encoding

So, in general: is there a way to avoid converting Unicode characters to their "nearest neigbours"?

EDIT

I know that calling colnames(df) gives appropriate results:

    (nm<-c('x\u00b2', 'y\u2082'))
    "x²" "y₂"
     
    colnames(df)<-nm

    colnames(df)
    "x²" "y₂"

My goal is to get them from simple df or print(df) call.

Those are escape sequences, not Unicode. This page is Unicode which is why I can write Αυτό Εδώ και Γ, γ, Σ, ω, Ω, β, Ψ knowing it will appear without problem, without any escape sequences or contacting SO support to have them change the way they store text — Panagiotis Kanavos, Feb 02 '21 at 08:58
Possible duplicate of this: https://stackoverflow.com/questions/44023570/r-unicode-characters-in-data-frame-names — T.G., Feb 02 '21 at 09:00
`are converted to "ordinary" digits` how do you display the characters? Are you sure the problem isn't your terminal or IDE? Or perhaps you need to explicitly set your environment on Linux or Mac to use UTF8? How is your environment set, eg the `LC_ALL` env variable? What OS, terminal, IDE are you using? If you use Mac, you may have to modify *two* profiles for the change to work — Panagiotis Kanavos, Feb 02 '21 at 09:00

Ian Campbell · Accepted Answer · 2021-02-03T13:51:11.357

2

I got the characters to stick by bypassing colnames<-:

attr(df,"names") <- nm
print(df)
  xβ y₂
1  1  4
2  2  5
3  3  6

colnames(df)
[1] "xβ" "y₂"

Use at your own risk.

sessionInfo()
#R version 4.0.2 (2020-06-22)
#Platform: x86_64-apple-darwin17.0 (64-bit)
#Running under: macOS Catalina 10.15.7
#
#Matrix products: default
#BLAS:   /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecL#ib.framework/Versions/A/libBLAS.dylib
#LAPACK: /Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib
#
#locale:
#[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

edited Feb 03 '21 at 13:51

answered Feb 02 '21 at 13:48

Ian Campbell

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Really sorry, but this works exactly like `colnames<-`. `colnames(df)` preserves `\uxxxx` sequences while simple `df` call does not. – Łukasz Deryło Feb 03 '21 at 07:04
Last command in your answer is `colnames(df)` and it works fine. But if you instead call just `df` you end up with `xß` and `y2`. The same is when you assign colnames with `colnames(df)<-nm`. See my edit. – Łukasz Deryło Feb 03 '21 at 13:46
Can you add a result of calling `print(df)` or simply `df` to your answer? – Łukasz Deryło Feb 03 '21 at 13:50
OK, I see. So I'll try to play with locale settings. Thank you! – Łukasz Deryło Feb 03 '21 at 13:50
Don't feel obligated to accept the answer if it doesn't solve your problem. Instead, maybe edit with your `sessionInfo()` like I show in my answer. – Ian Campbell Feb 03 '21 at 13:52
I changed locale and your solution worked :) – Łukasz Deryło Feb 04 '21 at 06:47

Unicode in column names

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