[R] removing blanks from a string

Prof Brian Ripley ripley at stats.ox.ac.uk
Fri Jun 27 13:07:26 CEST 2008


On Fri, 27 Jun 2008, john seers (IFR) wrote:

>
>
> Hello
>
> Yes, I am sure you are right. I guessed the intended question was not so
> specific.
>
> I have always thought of spaces and blanks as the same thing. And use
> "white space" for a more general catch all description for tabs etc.
>
> Is "white space" and "spaces" the same thing?

No.  There are

spaces [e.g. ASCII space]
blank characters [e.g. ASCII space and tab]
whitespace [e.g. ASCII space, tab and newline]

that are usually increasingly more general.  But CR, FF and VT are 
normally whitespace, and internationalized programs will generally allow 
other space characters, including nbspace (and Unicode category Zs).

>
>
> Regards
>
> JS
>
>
>
>
>
>
> ---
> -----Original Message-----
> From: Prof Brian Ripley [mailto:ripley at stats.ox.ac.uk]
> Sent: 27 June 2008 11:10
> To: john seers (IFR)
> Cc: jim holtman; juli pausas; R-help
> Subject: Re: [R] removing blanks from a string
>
> There are well-informed answers given as examples on the sub() help
> page.
>
> Hint 1: there is no need to globally substitute patterns anchored at the
> end: they can only match in one place.  There is also no need to
> substitute "" for "".
>
> Hint 2: 'blank characters' and 'spaces' are not the same thing.
> [:blank:] seems the relevant character class, so
>
> sub("[[:blank:]]+$", "", x)
>
> seems an accurate answer to the question asked (which might not be the
> question intended).
>
>
> On Fri, 27 Jun 2008, john seers (IFR) wrote:
>
>> There is also the "trim" command in the gdata package. Removes blanks
>> from the front of the string as well which may not be what you want.
>
> But that removes *spaces* and not *blanks*, according to the help page
> (and the actual code -- in fact it removes only ASCII space characters
> and not others such as nbspace).
>
>> Regards
>>
>> JS
>
>> -----Original Message-----
>> From: r-help-bounces at r-project.org
> [mailto:r-help-bounces at r-project.org]
>> On Behalf Of jim holtman
>> Sent: 27 June 2008 10:27
>> To: juli pausas
>> Cc: R-help
>> Subject: Re: [R] removing blanks from a string
>>
>> Is this what you want:
>>
>>> x <- c("hola    ", "Yes ", "hello           ")
>>> gsub(" *$", "", x)
>> [1] "hola"  "Yes"   "hello"
>>>
>>>
>>
>>
>> On Fri, Jun 27, 2008 at 4:34 AM, juli pausas <pausas at gmail.com> wrote:
>>> Hi
>>> Is there a way to remove blank characters from the end of strings in
> a
>>
>>> vector? Something like the =TRIM functions of the OpenOffice
>>> spreadsheet. E.g.,
>>> a <- c("hola    ", "Yes ", "hello           ")    # I'd like to get:
>>> c("hola", "Yes", "hello")
>>>
>>> Thanks
>>>
>>> Juli
>
> -- 
> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
>

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595



More information about the R-help mailing list