R help - Sep 2007 - Data manipulations with numbers which are in 'comma' format

Hi R,

 

May be a trivial question, but struggling to find a solution...

 

v=data.frame(a=c("1,234","2,345","5,567"))
> v
        a

1    1,234

2    2,345

3    5,567

 

I need a column 'b', which is just the addition of column 'a'
with 5.
How do I do it? And, entries in column 'a' are with commas, always.
Also, class(v$a)=factor.

 

BR, Shubha


	[[alternative HTML version deleted]]

Hi

> Hi R,
> 
> 
> 
> May be a trivial question, but struggling to find a solution...
> 
> 
> 
> v=data.frame(a=c("1,234","2,345","5,567"))
> 
> > v
> 
>         a
> 
> 1    1,234
> 
> 2    2,345
> 
> 3    5,567
> 
> 
> 
> I need a column 'b', which is just the addition of column
'a' with 5.
> How do I do it? And, entries in column 'a' are with commas, always.
> Also, class(v$a)=factor.
something like
> v$b <- as.numeric(gsub(",",  ".", v$a)) + 5
> v
      a      b
1 1,234  6.234
2 2,345  7.345
3 5,567 10.567

Regards

Petr
> 
> 
> 
> BR, Shubha
> 
> 
>    [[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org mailing list
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> PLEASE do read the posting guide 
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

Hi,
> I need a column 'b', which is just the addition of column
'a' with 5.
> How do I do it? And, entries in column 'a' are with commas, always.
> Also, class(v$a)=factor.
You must convert your factor with commas into a numeric variable,
first replacing commas with dots.

A very dirty way to do it could be the following, but there may be a
better one :

v$a <- as.numeric(gsub(",",".",as.character(v$a)))

HTH,

Julien

-- 
Julien Barnier
Groupe de recherche sur la socialisation
ENS-LSH - Lyon, France

Dear Shubha,
>  May be a trivial question, but struggling to find a solution...
>
>  v=data.frame(a=c("1,234","2,345","5,567"))
>
>>  v
>
>         a
>  1    1,234
>  2    2,345
>  3    5,567
>
>  I need a column 'b', which is just the addition of column
'a' with 5.
>  How do I do it? And, entries in column 'a' are with commas,
always.
>  Also, class(v$a)=factor.
if you are working (as me) in a locale where the comma is the decimal
separator, you should be awared that R is *very* good to cope with this
nightmare:

###
a <- c("1,234", "2,345", "5,567")
v <- read.table(textConnection(a), col.names = "a", dec =
",")
v$b <- v$a + 5
v
###
       a      b
1 1.234  6.234
2 2.345  7.345
3 5.567 10.567

Have a look at the "dec" argument in ?read.table. See also ?format.
Wonderful R, isn't it?

Best,

-- 
Jean R. Lobry            (lobry at biomserv.univ-lyon1.fr)
Laboratoire BBE-CNRS-UMR-5558, Univ. C. Bernard - LYON I,
43 Bd 11/11/1918, F-69622 VILLEURBANNE CEDEX, FRANCE
allo  : +33 472 43 27 56     fax    : +33 472 43 13 88
http://pbil.univ-lyon1.fr/members/lobry/